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Nanodiamond Batch Enriched with Boron: Properties and Prospects for Use in Agriculture

  • Institute of Silicate Chemistry of Russian Academy of Science, Sain-Petersburg, Russia
  • FSUE "SCTB "Technolog"
  • Agrophysical Research Institute

Abstract and Figures

The batch of detonation nanodiamond (DB) containing impurities of B (DB-B) was obtained by explosion using TNT with hexagon (50/50). This DB-B contained 0.96 wt% of B. The obtained DB-B nanopowder's morphological features, texture, and mesostructure were investigated by SEM, SAXS, and low-temperature nitrogen adsorption. We tested both aqueous suspensions and silica sols containing 2.5 wt. % DND and 0.05-0.1 wt. % of DB-B for the pre-sowing treatment of Chinese cabbage seeds. As a result, the reliable positive effect of an aqueous suspension of DB-B (0.05-0.1 wt.%) was revealed on the following characteristics of seedlings (in relation to the control): the germination energy of Chinese cabbage seeds and germination increased by ~50-70%. Furthermore, a significant positive effect of DB-B on the morphological characteristics of Peking cabbage plants at the early stages of its development was revealed when using DB-B for pre-sowing seed treatment in combination with silica sol (an increase in the sprout length by ~ 20% and root length by ~ 50% in relation to the control) as well as the biomass of Chinese cabbage plants increased by ~ 100% (20 days after planting the treated seeds).
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Volume 12, Issue 5, 2022, 6134 - 6147
Nanodiamond Batch Enriched with Boron: Properties and
Prospects for Use in Agriculture
Olga Shilova 1,2,* , Valery Dolmatov 3, Gayane Panova 4, Tamara Khamova 1, Alexandr
Baranchikov 5, Yulia Gorshkova 6,7 , Olga Udalova 4, Anna Zhuravleva 4, Gennady Kopitsa 8
1 Institute of Silicate Chemistry of Russian Academy of Sciences, Saint-Petersburg, Russia;, (T.K.);
2 St. Petersburg State Electrotechnical University "LETI", Saint-Petersburg, Russia; (O.S.);
3 Special Design and Technological Bureau "Technolog", St. Petersburg, Russia; (V.D.);
4 Agrophysical Research Institute, Saint Petersburg, Russia; (G.P.), (O.U.), (A.Z.);
5 Kurnakov Institute of General and Inorganic Chemistry of the Russian Academy of Sciences, Moscow, Russia; (A.B.);
6 Joint Institute for Nuclear Research, Dubna, Moscow Region, Russia; (Y.G.);
7 Kazan Federal University, Kazan, Russia; (Y.G.);
8 Konstantinov Petersburg Nuclear Physics Institute of NRC KI, Gatchina, Leningrad District, Russia; (G.K.);
* Correspondence: (O.S.); Scopus Author ID 6701888918
Received: 12.07.2021; Revised: 29.08.2021; Accepted: 5.09.2021; Published: 4.11.2021
Abstract: The batch of detonation nanodiamond (DB) containing impurities of B (DB-B) was obtained
by explosion using TNT with hexagon (50/50). This DB-B contained 0.96 wt% of B. The obtained DB-
B nanopowder's morphological features, texture, and mesostructure were investigated by SEM, SAXS,
and low-temperature nitrogen adsorption. We tested both aqueous suspensions and silica sols containing
2.5 wt. % DND and 0.05-0.1 wt. % of DB-B for the pre-sowing treatment of Chinese cabbage seeds.
As a result, the reliable positive effect of an aqueous suspension of DB-B (0.05-0.1 wt.%) was revealed
on the following characteristics of seedlings (in relation to the control): the germination energy of
Chinese cabbage seeds and germination increased by ~50-70%. Furthermore, a significant positive
effect of DB-B on the morphological characteristics of Peking cabbage plants at the early stages of its
development was revealed when using DB-B for pre-sowing seed treatment in combination with silica
sol (an increase in the sprout length by ~ 20% and root length by ~ 50% in relation to the control) as
well as the biomass of Chinese cabbage plants increased by ~ 100% (20 days after planting the treated
Keywords: carbon nanomaterials; diamond batch; boron; pre-sowing seed treatment.
© 2021 by the authors. This article is an open-access article distributed under the terms and conditions of the Creative
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1. Introduction
In the last decade, nanotechnology has been successfully used in agriculture [1-6].
Including nanoparticles of carbon materials (carbon nanotubes, fullerenes, fullerenols, and their
adducts with amino acids, carboxylates, etc.) are being actively studied for use in agriculture
[1,7-12]. Researchers are attracted by low concentrations of used carbon nanoparticles and their
adducts, relative cheapness, and non-toxicity. Aqueous suspensions of carbon nanotubes, incl.
functionalized with hydroxyl groups, solutions of fullerenols, and their adducts (i.g., with
amino acids) can be used for pre-sowing seed treatment and the root environment and foliar
treatment of vegetative plants. In general, such treatments promote better seed germination and
plant growth, increase plant resistance to oxidative stress and high salt content in the soil, and
increase the amount of biomass of various plants. The use of carbon nanomaterials as
stimulants for the growth of plants and crops is of interest to the scientific community and
industrialists. The mechanisms of the influence of carbon materials on the growth and
development of plants are actively studied. At the same time, various factors such as size,
shape, surface structure, solubility, and concentration of nanoparticles, including carbon
nanomaterials, as well as the presence of functional groups, contribute significantly to plant
digestibility, as well as to toxicity and pathology caused by their use [7,13]. Therefore, the use
of carbon materials in agriculture requires a thorough preliminary study of both the properties
of the materials themselves and the effect of their effect on each type of plant.
It is known that detonation nanodiamond (DND) has bactericidal and fungicidal
properties [14-16]. DND is widely researched for medical purposes, particularly as drug
delivery [17-19]. However, the use of nanodiamonds (DND) in agriculture is less well known.
Large volumes of reagents are needed for agricultural applications, purification is less
important, but it is important that they would be cheap. The detonation nanodiamond (DB)
batch also has a scientific and practical interest since it is much cheaper than DND. The cost
of DB is 3-5 times less than the cost of purified DND (~$ 300 per 1 kg). At the same time, it
can have a whole range of useful properties.
Of particular interest are the DND and DB, enriched with various elements that give it
new useful properties [20-22]. The DB has a very complex structure containing both DND
proper and other non-diamond forms of carbon. DB doped with heteroatoms (i.g., B, Si, etc.)
have an even more complex composition. The problem of studying such complex compositions
is extremely urgent. The DB containing impurities B (DB-B) was obtained in the Special
Design Bureau "Technolog" (St. Petersburg, Russia). The DB-B was synthesized by explosion
using TNT with hexagon as precursors [23-25]. This object has not been studied enough. It was
important to study the structure of the DB-B. It was interesting to test this DB-B for seeds pre-
sowing to study the effect on germination, growth, and development of plants.
Silicon compounds also promote plant growth and development [26-29]. Our earlier
researches have shown that the treatment of seeds of spring barley and Chinese cabbage with
silica sol is obtained by hydrolysis of tetraethoxysilane (TEOS), incl. with the addition of a
number of elements useful for plants (in trace amounts) positively affects the development of
plants in the early stages of development [30,31]. It was useful to compare the effect of DND
and DB-B on plants, both in the form of aqueous suspensions and in combination with the
TEOS-derived silica sols.
Thus, this work aimed to study the structure of the DB powders and test there for pre-
sowing treatment of seeds of Chinese cabbage, along with the treatment of seeds directly with
DND, as well as in combination with TEOS-derived silica sols.
2. Materials and Methods
2.1. Nanopowders synthesis.
Diamond batch enriched with B (DB-B) was obtained by explosion using a mixture of
TNT with hexagon.
A non-crystalline amorphous powder containing boron was used as a dopant containing
92-94 wt.% B and a density of ~2.3 g/cm3. This powder was obtained by sintering boric acid
with magnesium, and then the sinter was treated at 70 ± 2° C with a 15-20 % hydrochloric acid
solution. The precipitate was washed, dried, and calcined in a vacuum. [32].
The dopant (2.5 wt.% B) was introduced into an explosive (TNT with hexogen). The
mixture powders were thoroughly mixed and pressed at a pressure of 1500 kg/cm2. The charges
had a diameter of 60 mm, a length of 107-110 mm, and a mass of 0.5 kg. The charges were
detonated in an Alfa-2M explosive chamber with a volume of 2.14 m3. Each charge had a water
shell (explosive: H2O = 1 : 10). The resulting DB-B composition after the explosion prepared
using both TNT with hexogen is presented in Table 1.
Table 1. Composition of boron-enriched diamond batch (DB-B).
Sample designation
Content, wt.%
Non-combustible impurities
TH 50/50
Note: TH a mixture of TNT with hexagen, DND detonation nanodiamond.
To obtain the thermal-ammonia-treated detonation nanodiamond (DND-TAN), the
diamond batch (DB) was subjected to nitric acid purification, namely: it was treated with 40%
nitric acid at a temperature of 225-240 ° C for 1 h at 80-100 atm. [33]. The obtained purified
DNDs were washed from traces of acid to pH 6-7, then; aqueous ammonia was added to pH
11-12, heated to 230° C, and kept at this temperature for 1 h; the pressure in the autoclave was
40-50 atm. [34]. DND, after thermal ammonia treatment, had nitrogen-containing functional
groups on its surface. Such DND was designated as DND-TAN. After such treatment, the
amount of incombustible impurities drops by 2-2.5 times relative to DND after nitric acid
cleaning, and the size of the aggregates in the aqueous suspension decreases 2-3 times. In this
regard, DND-TAN is preferably used directly in the form of an aqueous suspension. The
structure and properties of DND-TAN are described in [25,35].
2.2. Powder research methods.
The obtained DB-B nanopowder's morphological features, texture, and mesostructure
were investigated by SEM, SAXS, and low-temperature nitrogen adsorption.
The morphology of nanoparticles (size, shape, and degree of their aggregation) was
studied by scanning electron microscopy (SEM), which was performed using a scanning
electron microscope with a field emission cathode (FE-SEM) ZeissMerlin.
An experiment on small-angle neutron scattering (SANS) on DB-B was carried out on
a YuMO spectrometer located at channel 4th of the IBR-2 pulsed reactor (Dubna, Russia) in a
two-detector configuration using the time-of-flight method [36]. The flux of thermal neutrons
was formed by a system of collimators so that the neutrons hitting the sample formed a beam
of 14 mm in diameter with an intensity of up to 4x107 neutrons. As a result, the range of the
transferred momentum q was 6.5 103 0.4 Å-1 (q = 4sin /, where is the neutron
wavelength and is the scattering angle), which corresponds to the analysis of the structure in
the range of characteristic sizes from 10 up to 500 angstroms.
A sample of the DB-B was placed in an aluminum cell with a 1 mm depression. The
processing of the initial experimental data was carried out by the SAS program [37], which
allows the obtained spectrum to be normalized to an independent vanadium scatterer, taking
into account the scattering from the setup and the aluminum cell, as well as the background of
the hall [38].
Measurements of the specific surface area of the sample of the DB-B were performed
by low-temperature nitrogen adsorption using QuantaChrome Nova 1200e analyzer. The
powder was degassed at 150°C in a vacuum for 17 h prior to analysis. Based on the data
obtained, the specific surface area SBET was calculated for the samples using the Brunauer
EmmettTeller model (BET) and the seven points method within the relative pressure range of
P/P0 = 0.07 ÷ 0.25 (where P0 is the saturation pressure). In addition, the calculation of the pore
size distribution was carried out based on nitrogen isotherms using the Barrett-Joyner-Halenda
(BJH) method.
2.3. Seed treatment preparations.
Both aqueous suspensions with DND or DB-B and silica sols with and without DND
or DB-B were used for pre-sowing seed treatment. The aqueous suspensions of DND or a batch
are of particular interest as precursors of composite materials or as biologically active additives
since colloidal carbon nanoparticles in an aqueous dispersion medium are the most chemically
reactive [39].
The silica sols differing in concentration ratios of the main components, the acidity of
the medium, and modifying additives were prepared. Tetraethoxysilane Si(OEt)4 (TEOS),
special purity grade; hydrochloric acid (HCl), special purity grade, in the form of 0.25 N
aqueous solution; potassium hydroxide (KOH) high-purity grade, in the form of a 0.1 N
aqueous solution were used as precursors for the preparation of silica sols.
DND-TAN in the form of a 3 wt.% aqueous suspension or DB-B in the form of a
powder was introduced into silica sols as modifying additives.
The following compositions were prepared: 0.08 g DND per 1 ml of water or a silica
sol (2.5 wt.% DND); 0.002 g DB-B per 1 ml of water or a silica sol (0.05 wt. % DB-B), and
0.003 g per 1 ml of water or a silica sol (0.1 wt. % DB-B).
The preparation of silica sols was carried out according to a one-stage method of acidic
or alkaline hydrolysis of TEOS with an excess of water.
The one-stage procedure consisted of sequential mixing of the initial components:
Si(OEt)4, 0.25 N HCl and/or 0.1 N KOH. As a result, the silica sols were obtained. The
description of these compositions is presented in Table 2. As a result, a silica sol was obtained,
the composition of which is shown in Table 2.
Table 2. Compositions of silica sols and aqueous suspensions used for the pre-sowing treatment of Peking
cabbage seeds
The ratio of the initial components
Si(OEt)4, vol.%
0.25N HCl, vol.%
0.1 N KOH, vol.%
2.4. Pre-sowing seed treatment.
Pre-sowing seed treatment was carried out as a result of mixing for 10 minutes by
simply shaking the seeds in containers with water (control) and the above solutions of
substances and their compositions. The seeds were dried at room temperature in the air and
then at 30° C for 60 min in an oven. Seed drying regimes corresponded to those specified in
GOST 12038. Treated seeds were stored at room temperature before sowing. The repetition of
the experiment was 400 seeds for each variant of the experiment.
2.5. Procedure for assessing the biological activity of the tested substances.
The effect of the tested substances on plants was evaluated in laboratory conditions and
on a polygon with partial or complete regulation of microclimate conditions. Chinese cabbage
of the Daqingkou variety (China, k-56), adapted to intensive plant artificial-light culture
conditions, was the study's object. The seeds were obtained from the collections of the N.I.
Vavilov All-Russian Institute of Plant Genetic Resources (VIR).
2.5.1. Methodology for determining the germination energy and germination capacity.
Control and treated with test seed treatment preparations Chinese cabbage seeds were
germinated in Petri dishes (10 cm in diameter) on filter paper moistened with 10 ml of distilled
water. The seed germination energy was assessed on the 3rd day, germination on the 7th day;
the length of shoots and roots of seedlings was also measured. The researches were carried out
in accordance with the rules of the International Seed Testing Association (ISTA) and generally
accepted methods. All experiments were repeated three times.
2.5.2. Methodology for assessing the effect of pre-sowing seed treatment on plant growth and
The study of the effect of pre-sowing treatment of the seeds of Chinese cabbage variety
Daqingkou with the tested preparations on the growth and development of plants was carried
out in a greenhouse with partially controlled microclimate conditions under natural
illumination, an air temperature of 20-25° C during the day, 18-20 ° C at night, and relative
humidity of 60 - 70%. The plants were grown on a substrate based on high-moor peat with a
low degree of decomposition with the addition of macro-and microelements in the composition
of Knop nutrient solution. The moisture content of the substrate was maintained at 60% of the
total moisture capacity. The plants were harvested at the age of 20 days. Plants whose seeds
were treated with water served as control.
At the end of the growing season, the main plant growth and development indicators
were taken into account.
Statistical data processing was carried out using Excel 2010 and Statistica 8 software
(Stat-Soft, Inc., USA). The mean values of the studied indicators, confidence intervals, and
coefficients of variation were determined. The significance of the differences between the
variants was assessed using the methods of parametric statistics (Student's t-test). Differences
between the options were considered significant at p ≤ 0.05.
3. Results and Discussion
3.1. Boron-enriched diamond batch surface morphology.
3.1.1. Scanning electron microscopy data.
The surface morphology of DB-B powder, as well as the change in the surface
morphology of the Peking cabbage seeds as a result of pre-sowing treatment in DB-B aqueous
suspension and in a silica sol with the addition of DB-B, can be estimated from SEM images
in Figures 1 and 2.
Figure 1. SEM image of DB-B powder.
DB-B powder consists of non-spherical, close to plate shape particles (Figure 1).
It can be stated that the state of the seed surface changed (Figure 2). As a result of the
pre-sowing treatment of seeds, a thin film appears on their surface, consisting of DB-B
nanoparticles and silica (in the case of using silica sols).
Figure 2. SEM image of the surface of Peking cabbage seeds without any treatment (a) and after treatment with
TEOS-derived silica sol (1%, pH 2-3) (b), an aqueous suspension of a diamond batch enriched with boron (0.1
wt.% DB-B (c), and the silica sol with the addition of DB-B (0.1 wt.%) (d).
3.2. Boron-enriched diamond batch mesostructure.
3.2.1. Low-temperature nitrogen adsorption data.
The obtained isotherm (Figure 3 a) is characterized by pronounced capillary-
condensation hysteresis and belongs to type IV according to the IUPAC classification (The
International Union of Pure and Applied Chemistry Classification).
Figure 3. Full nitrogen adsorption-desorption isotherm (a) and pore size distribution dV(d) obtained within the
BJH model (b) for the DB-B powder.
The shape of the hysteresis loop for this sample corresponds to the classical H3 type
according to the IUPAC classification, usually associated with the presence of slit-like pores
typical for the materials consisting of flat particles. The hysteresis loop closes at a relative
pressure P/P0 significantly higher than 0.3, which indicates the absence of the micropores in
this sample.
Mathematical processing of the full nitrogen adsorption-desorption isotherm within the
BJH model made it possible to obtain the pore size distributions shown in Fig. 3 b. It is clearly
seen from this figure that the sample of the DB-B powder is characterized by a practically
normal distribution of dV(d) with a maximum of dp 9 nm. The results of determining the
texture parameters of DB-B powder are shown in Table 3.
Table 3. Textural parameters of the DB-B powder.
SBET (m2/g)
Vsp (P/P0 0.995) (cm3/g)
dp (nm) BJH (des)
296 ± 6
Note: SBET specific surface area; Vsp specific pore volume; dp average pore diameter.
3.2.2. Data Small-Angle Neutron Scattering Data.
Figure 4 shows the experimental log-log plot of neutron scattering cross sections
dΣ(q)/dΩ versus the momentum transfer q for DB-B powder. As can be seen from this figure,
there are three different ranges in q on the corresponding curves, in which the behavior of the
small-angle scattering cross-section d
is very different.
The scattering in the region q < 0.35 Å is characterized by the presence of two ranges
on the corresponding curve d
: q > qc (Guinier region) and q < qc (Porod region) with
the point of crossover between them is qc 0.11Å-1 (the point of transition from one scattering
regime to another) where the scattering obeys the power laws q- with different values of
exponents = s and n, respectively.
This pattern is typical for scattering on porous systems (solid-phase pore) consisting
of randomly oriented non-spherical (anisodiametric) inhomogeneities, for example, for highly
elongated or flattened particles or pores [40, 41], which is consistent with the results obtained
for this sample using scanning microscopy methods (Figure 1) and low-temperature nitrogen
adsorption (Figure 4). In order to describe scattering in the Guinier region, which is determined
by the size Rс and shape of scattering inhomogeneities, one should use the generalized
relationship [42]:
  
 , (1)
where the amplitude G is directly proportional to the product of the number of inhomogeneity's
in the scattering volume and the square of the average density
of the scattering amplitudes
on them [43], Rg is the radius of gyration of scattering inhomogeneities, and the parameter s is
determined by the shape of the scattering inhomogeneities. s equals 0 for spherical objects, s
equals 1 for one-dimensional particles or pores, and s equals 2 for two-dimensional
inhomogeneities. The values of the parameter s can be not only integer but also fractional, for
example, if the scattering inhomogeneities have the shape of an ellipsoid of rotation or the
presence of heterogeneities of various shapes in the system.
Since non-spherical items are defined not by one but by two characteristic dimensions
(radius Rc and length L in the case of elongated inhomogeneities) or three (thickness T, width
W, and length L for flattened inhomogeneities), the Guinier region can comprise two or three
momentum transfer q ranges. The presence of only one power-law section in the Guinier region
(Fig. 3) indicates that the length L (in the case of elongated inhomogeneities) or the width W
(for flattened inhomogeneities) exceeds the maximum size that can be determined using the
setup used in the experiment. Nevertheless, using the ratio Rmax 3.5/ qmin [44], it is possible
to estimate this size, which was Rc > 550 Å.
Figure 4. The dependence of the cross-section of small-angle neutron scattering d(q)/d versus the
momentum transfer q for the powder DB-B. Solid lines result from the description of experimental data using
formulas (1) and (2).
The values of the exponents of the degree s and n, which were determined from the
slope of the linear parts of the SANS curve in the ranges: 0.11 < q Å-1 and 0.11 < q < 0.35 Å-
1, are equal to s = 2.08 ± 0.02 and n = 3.92 ± 0.04, which corresponds to scattering on
inhomogeneities (pores) of a flattened (slit-like) shape with a surface close to a smooth
surface (Ds = 6 n = 2.08 ± 0.04).
In view of the above, to analyze the scattering curve d
for DB-B powder, we
use the generalized empirical Guinier-Porod model [42]:
In view of the above, to analyze the scattering curve d
for the powder DB-B,
we use the generalized empirical Guinier-Porod model [42]:
  
 at q < qc,
at qc < q < 0.35 Å.
Here (3 s) is the dimension factor; Rg is the gyration radius of non-spherical
scattering inhomogeneities. For flattened inhomogeneities with thickness T: Rg = T/121/2. G
is the gyration radius of non-spherical scattering inhomogeneities. For flattened
inhomogeneities with thickness [42, 45]; B the coefficient depending on the local structure
of scattering inhomogeneities [46].
In the range of large q > 0.35 Å-1, the appearance of the so-called "shoulder" on the
scattering curve is observed, which indicates the presence of small spherical
inhomogeneities in the system, possibly particles of non-combustible impurities, with a
characteristic size r0. In this case, the behavior of the scattering cross-section d(q)/d is also
described by the Guinier approximation (1) with the parameters s = 0 and r0 = (5/3)1/2rg [45].
To obtain the final results, Eq. (1) and Eq. (2) were convoluted with the instrumental
resolution function. The experimental dependences of the differential scattering cross-section
dΣ(q)/dΩ were processed using the least-squares method throughout the entire range under
study. The results of the analysis are shown in Figure 3 and Table 4.
Table 4. Structural parameters of the powder DB-D obtained from the analysis of SANS data.
T, Ǻ
r0 = (5/3)1/2rg,
4.6 ± 0.3
2.08 ± 0.02
24.9 ± 0.4
2.8 ± 0.2
3.92 ± 0.04
0.56 ± 0.10
4.7 ± 0.5
3.3. Biological activity of seed pre-sowing treatment preparations.
3.3.1. Morphometric indicators of plant development at early stages of development.
Pre-sowing treatment of Chinese cabbage seeds with aqueous suspensions of DND and
DB-B separately or combined with TEOS-derived silica sols showed a predominantly positive
effect on seed germination and growth parameters of plant seedlings (Table 5).
Table 5. Influence of seed pre-sowing treatment of Chinese cabbage variety Daqingkou (China, k-56) with
tested preparations on their germination and growth characteristics of seven-day seedlings
Seed treatment
Germination energy
Sprout length
Root length
% to
% to
% to
% to
H2O (control)
2.5 % DND-TAN
0.05 % DB-B
0.1 % DB-B
Silica sol
1 % TEOS
pH 7-8
Silica sol
1 % TEOS + 0.1 %
pH 7-8
Aqueous suspensions of DB-B (0.05-0.1 wt.%) had a positive effect on germination
energy and germination capacity. Their efficiency, according to this indicator, is significantly
higher than for DND-TAN suspension (2.5 wt.%). The sizes of sprouts and roots turned out to
be the highest when seeds were treated with silica sol based on TEOS (1 vol%, pH 7-8) with
the addition of DB-B (0.1 wt%). In other cases, approximately the same effect was noted.
The positive effect of pre-sowing treatment of Chinese cabbage seeds with an aqueous
suspension of DB-B (0.1 wt.%) and TEOS-derived silica sol on the growth and development
of plants at the early stages of development persists for 20 days of plant cultivation (Table 6).
Table 6. Morphometric parameters of plants of Chinese cabbage variety Daqingkou (China, k-56), the seeds of
which were pre-sowing treated with tested preparations (plant age 20 days).
Pre-sowing treatment
Height, cm
Number of
Leaf length,
Leaf width,
Wet weight
% of
H2O (control)
Heteroauxin 10 mg/L (reference
for comparison)
Aqueous suspension
0.1 % DB-B
Silica sol, 1% TEOS, pH 7-8
Silica sol, 1% TEOS + 0.1%
DB-B, pH 7-8
Note: The values are significantly different from the control at the 5% significance level is marked with the sign (*).
A pronounced synergistic effect on the formation of plants with higher biomass and the
growth rates of plants from using DB-B additive together with silica sol may be noted.
4. Conclusions
The advanced carbon nanopowder the boron-enriched diamond batch (DB-B)- was
synthesized by detonating TNT with hexagen (50/50). The resulting DB-B contained 14.7 wt.%
DND, 0.96 wt.% B and 3.5 wt.% of incombustible impurities. According to SEM and low-
temperature nitrogen adsorption data, DB-B powder had a high specific surface area SBET ~300
m2/g, consisting of lamellar mesoporous nanoparticles, with slit pores of the pore average size
~9 nm, practically without micropores. The SANS data confirmed the results obtained by other
research methods. The DB-B powder consisted of randomly oriented non-spherical
(anisodiametric) inhomogeneities, highly elongated or flattened particles (and/or pores). The
size of carbon nanoparticles can be characterized by the following parameters: thickness T ~
2.5 nm and width (W) or length (L) > 55 nm. Some spherical nanoparticles (~0.5 nm) were
found, which are apparently formed by incombustible impurities. DB-B was tested as a
biologically active additive (0.05-0.1 wt.%) for the pre-sowing treatment of Chinese cabbage
seeds (variety Daqingkou, China, k-56). As a result, the reliable positive effect of an aqueous
suspension of DB-B (0.05-0.1 wt.%) was revealed on the following characteristics of seedlings
(in relation to the control): the germination energy of Chinese cabbage seeds and germination
increased by ~50-70%. A significant positive effect of DB-B on the morphological
characteristics of Chinese cabbage plants at the early stages of its development was revealed
when using DB-B for pre-sowing seed treatment in combination with silica sol (an increase in
the sprout length by ~ 20% and root length by ~ 50% in relation to the control) as well as the
biomass of plants Chinese cabbage increased by ~ 100% (20 days after planting the treated
This research was funded by the Russian Science Foundation, grant number 19-13-00442 in
terms of studying the structure and properties of carbon materials.
The SEM measurements were performed using shared experimental facilities supported by
IGIC RAS (Moscow, Russia) state assignment. The authors are grateful to the Joint Institute
for Nuclear Research (Russia) for the possibility of extended performance of the SANS
experiment at the IBR-2 pulsed reactor (Dubna, Russia).
Conflicts of Interest
The authors declare no conflict of interest.
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... At the same time, it is the charge that can be of practical interest, for example, in the synthesis of composite materials and coatings [13]. It can find application in agriculture as an inexpensive reagent with properties beneficial to plants [14]. The charge of detonation nanodiamond, enriched with elements useful for plants, for example, boron, is particularly interesting. ...
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Two versions of powders of a charge of detonation nanodiamond doped with 0.96 and 0.73 wt % boron are obtained by explosion using a mixture of TNT with hexogen (TG) (50/50) or tetryl, respectively. Their morphology, texture, and mesostructure are investigated by scanning electron microscopy, small-angle neutron scattering, and low-temperature nitrogen adsorption. A significant effect of the explosion's precursor on the structure and morphology of the obtained carbon nanopowders is found.
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Structural analysis in the range of characteristic sizes from 1 nm to ~1.5 μm was performed for SiO2-TiO2 aerogels prepared in supercritical CO2 , isopropanol, hexafluoroisopropanol, or methyl-tert-butyl ether using small-angle X-ray scattering and neutron scattering complementary methods. A two-level model that accounts for scattering by individual inhomogeneities and their aggregates, which have fractal properties, satisfactorily describes the aerogel structures over the entire range of scales. It is shown for the first time that the titania concentration is the key factor in the small-angle neutron and X-ray scattering by SiO2-TiO2 aero-gels. The phase composition of an aerogel does not significantly affect the aerogel structure in the range of scales from 1 nm to ~1.5 μm, as probed by small-angle X-ray and neutron scattering.
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The laboratory research was attempted to find nano zinc fertilizer utilizing the carbon sphere as a substrate. Typically the encapsulation techniques are followed in the drug delivery system, the limited work was done in nano-based zinc micronutrient for slow release of nutrients to crop. The use efficiency of zinc micronutrients in the soil is only less than 6 percentage. In universal, the deficiency of zinc micronutrients causes malnutrition problems in human beings, especially in children. After considering this problem we planned to prepare zinc nano fertilizer by using the carbon sphere for need-based slow release and increase the use efficiency of zinc micronutrient in soil. In this study we synthesis the carbon sphere nanoparticle after the formation of carbon sphere the zinc sulphate was loaded and characterized by utilizing Scanning Electron Microscopy, Surface Area and Porosity, X-ray diffraction analysis, Fourier Transform Infrared Spectroscopy, Transmission Electron Microscopy. The research result shows that the nano carbon sphere was excellently loaded with zinc sulphate to the tune of 8 percentage and it was confirmed by Energy dispersive X-beam spectroscopy. The zinc loaded carbon sphere release nutrient for a prolonged period of up to 600 h in the case of conventional zinc sulphate zinc release halted after 216 h in percolation reactor studies. The zinc nano fertilizer is recommended in agriculture to increase zinc use efficiency, crop yield without any environmental risk.
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Agriculture must overcome several challenges in order to increase—or even maintain—production, while also reducing negative environmental impact. Nanotechnology, fundamentally through the development of smart delivery systems and nanocarriers, can contribute to engineering more efficient and less contaminant agrochemicals. This Collection presents recent related works, covering nanodevices that improve crop protection against pests and diseases, nanoformulations for enhancing plant nutrition, and nanomaterials strengthening the general crop performance.
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Nanotechnology is a tool that in the last decade has demonstrated multiple applications in several sectors, including agroindustry. There has been an advance in the development of nanoparticulated systems to be used as fertilizers, pesticides, herbicides, sensors, and quality stimulants, among other applications. The nanoencapsulation process not only protects the active ingredient but also can affect the diffusion, interaction, and activity. It is important to evaluate the negative aspects of the use of nanoparticles (NPs) in agriculture. Given the high impact of the nanoparticulated systems in the agro-industrial field, this review aims to address the effects of various nanomaterials on the morphology, metabolomics, and genetic modification of several crops.
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Carbon nanotubes (CNTs) are considered a promising nanomaterial for diverse applications owing to their attractive physicochemical properties such as high surface area, superior mechanical and thermal strength, electrochemical activity, and so on. Different techniques like arc discharge, laser vaporization, chemical vapor deposition (CVD), and vapor phase growth are explored for the synthesis of CNTs. Each technique has advantages and disadvantages. The physicochemical properties of the synthesized CNTs are profoundly affected by the techniques used in the synthesis process. Here, we briefly described the standard methods applied in the synthesis of CNTs and their use in the agricultural and biotechnological fields. Notably, better seed germination or plant growth was noted in the presence of CNTs than the control. However, the exact mechanism of action is still unclear. Significant improvements in the electrochemical performances have been observed in CNTs-doped electrodes than those of pure. CNTs or their derivatives are also utilized in wastewater treatment. The high surface area and the presence of different functional groups in the functionalized CNTs facilitate the better adsorption of toxic metal ions or other chemical moieties. CNTs or their derivatives can be applied for the storage of hydrogen as an energy source. It has been observed that the temperature widely influences the hydrogen storage ability of CNTs. This review paper highlighted some recent development on electrochemical platforms over single-walled CNTs (SWCNTs), multi-walled CNTs (MWCNTs), and nanocomposites as a promising biomaterial in the field of agriculture and biotechnology. It is possible to tune the properties of carbon-based nanomaterials by functionalization of their structure to use as an engineering toolkit for different applications, including agricultural and biotechnological fields.
The article describes a complex study of detonation nanodiamonds (DND) aqueous dispersions. In this research, DND sample was characterised by means of IR, NMR spectroscopy, TEM, thermogravimetric analysis, size distribution, and ζ-potentials. It was shown that DND sample includes several surface groups, mainly hydroxylic, carboxylic, and carbonyl ones. Dynamic light scattering results revealed that in the concentration range C = 0.002–0.3 wt%, DND nanoparticles size is equal to 55 ± 5 nm. It was demonstrated that DND possessed weak antiradical activity, had an inhibitory effect on F1F0-ATPase activity, almost did not affect platelet aggregation, formed a stronger complex with human serum albumin (HSA) in subdomain IB (digitoxin, Kb = 20.0 ± 2.4 l·g⁻¹) and a less strong complex in subdomain IIA (warfarin, Kb = 3.7 ± 0.1 l·g⁻¹), inhibited the esterase activity of HSA, DND dispersions (C = 0.0012–0.15 wt%) revealed genotoxic effect towards PBMCs, did not affect cellular proliferation in the experiment with HEK293 cell line, did not reveal cytotoxic effect up to 0.01 wt%. Using DFT and MD approaches allowed us to perform a simulation of interaction between DND nanoparticle and water molecules.
Relevance. Cucumber in the Russian Federation in protected ground in terms of growing areas and production volume is the first, its share in the total production of greenhouse products in recent years accounts for about 50-55%. Scientific research confirms the positive effect of silicon-containing agrochemicals on the intensity of metabolic processes in the plant body, which is manifested in increasing the yield of commercial products, resistance to adverse environmental factors, and the realization of the biological potential of crops. Methods. The aim of the research is to evaluate the effect of silicon – containing fertilizers on the productivity of Cyborg F 1 cucumber in low-volume cultivation technology. The research was conducted in the winter-spring period of 2020 in the conditions of a winter glazed greenhouse of the greenhouse complex of the Stavropol state agrarian university. The objects of research were cucumber Cyborg F 1 , fertilizers Kelik Potassium Silicon, Siliplant, Forris, Bio Silicium. Fertilizers were applied to foliar top dressing three times during the cucumber growing season. All microclimate conditions in the greenhouse were regulated automatically using the Sercom climate program. Mineral wool was used as a substrate. Results. Fertilizing with silicon – containing fertilizers increased the degree of assimilation of nutrients by plants of cucumber Cyborg F 1 : the nitrogen content in the drainage solution decreased by 6-26 mg/l, phosphorus – by 4-8 mg/l, and potassium-by 18-34 mg/l. The use of silicon-containing fertilizers contributed to an increase in the area of cucumber leaves compared to the control by 1.6-3.1%, the yield of standard products-by 3.7-8.1%, yield-by 0.9-2.5 kg/m ² , and a decrease in the degree of ovary death – by 2.0-3.5%. When using silicon-containing fertilizers, the quality of cucumber products improved. Thus, in the conditions of the sixth light zone, to increase the yield of Cyborg F 1 cucumber in low-volume cultivation technology, it is recommended to use silicon-containing fertilizers Siliplant and Forris, which provides an increase relative to the control of 7.4 and 9.2%, respectively.
Conventional agriculture often relies on bulky doses of fertilizers and pesticides that have adversely affected the living beings as well as the ecosystems. As a basic tenet of sustainable agriculture, minimum agrochemicals should be used so that the environment can be protected and various species can be conserved. The application of nanotechnology in agriculture can significantly enhance the efficiency of agricultural inputs and thus it offers a significant way to maintain sustainable development of agroecosystems via nanoparticles. In this regard, nano-plant growth promoters, nanopesticides, nanofertilizers, nano-herbicides, agrochemical encapsulated nanocarrier systems etc. have been developed for the potential applications in agriculture. These can have great benefits for agriculture, including higher production of crops, inhibition of plant pathogens, removal of unwanted weeds and insects with lesser cost, energy and waste production. However, there are several concerns related to the use of nanoparticles in agriculture. These include the approaches for synthesis, their mechanisms of penetration to applied surfaces and the risks involved. Though, advent of new technologies has significantly improved the synthesis and application of nanomaterials in agriculture, there are many uncertainties regarding nano-synthesis, their way of utilization, uptake and internalization inside the crop cells. Therefore, an elaborate investigation is required for deciphering the engineered nanomaterials, assessing their mechanistic application and agroecological toxicity. Hence, this review is aimed to critically highlights the NPs material application and pointed the vital gaps in the use of nanotechnology for sustainable agriculture.
Objectives Detonation nanodiamonds (DND) with Gd3+ ions directly grafted to the DND surface have recently demonstrated enhanced relaxivity for protons in aqueous suspensions. Herewith, the relaxivity measurements were done on a series of suspensions with the gadolinium content varied by changing number of Gd3+ ions grafted per each DND particle whereas the DND content in each suspension was kept the same. Such an approach to vary the contrast agent content differs from that commonly used in the relaxivity measurements. In the common approach, contrast agents are directly dissolved/suspended in media. Aiming to test validity of the unconventional approach, in the present study we follow the common way of measurement relaxivity: using variable concentrations of carriers (DND particles) in aqueous suspension keeping the number of Gd3+ ions per each carrier fixed.Materials and methods1H NMR relaxation measurements of aqueous suspensions of DND with Gd3+ ions directly grafted to the DND surface were carried out at room temperature (293 K or 20 °C) in the external magnetic field B0 = 8.0 T.Results and conclusionsComparative study of two approaches for measuring relaxivity in suspensions containing DND as magnetic entities' carriers reveals complete identity of techniques in use.