Prabhat K. Dwivedi

Prabhat K. Dwivedi
Indian Institute of Technology Kanpur | IIT Kanpur · Centre for Nanoscience

Ph. D.
Nanomaterial, microfluidic devices, integrated detection platform, sensor design and fabrication

About

83
Publications
15,176
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1,321
Citations
Citations since 2017
34 Research Items
842 Citations
2017201820192020202120222023050100150200
2017201820192020202120222023050100150200
2017201820192020202120222023050100150200
2017201820192020202120222023050100150200
Introduction
Prabhat K. Dwivedi is an experimental physicist and working in the material science and Nanotechnology research domain from last 10 years. He obtained his Ph.D. from the Harcourt Butler Technological Institute, Kanpur and postdoctoral training from the University of Alberta/TR Labs, Edmonton, Canada, in the photonics group before joining Centre for Nanosciences at IIT Kanpur. Currently, he is working as Senior Scientific Officer at Center for Nanosciences, Indian Institute of Technology Kanpur,
Additional affiliations
January 2014 - July 2015
Indian Institute of Technology Kanpur
Position
  • Research Officer
January 2014 - December 2021
Indian Institute of Technology Kanpur
Position
  • Research Officer
July 2006 - December 2013
Indian Institute of Technology Kanpur
Position
  • Researcher
Description
  • The Centre for Nanosciences at IIT Kanpur is a state of the art research facility for carrying out research in the area of nanotechnology. This facility is aimed to provide interdisciplinary academic research platform of different department of the IITK

Publications

Publications (83)
Article
We design and synthesize nanohybrids composed of Silver nanoparticle (AgNPs) with Nitrogen doped (N-rGO) and Nitrogen-Sulphur co-doped (NS-rGO) with GO, SERS probes for the detection of hazardous materials. Graphene oxide (GO) was synthesized using Hummer’s method, subsequently N-rGO and NS-rGO were achieved by hydrothermal treatment. GO showed she...
Article
Full-text available
Herein, a novel Microfluidic-biochip enabled with Surface Enhanced Raman Spectroscopy (SERS) as a readout has been demonstrated for Uric acid (UA) detection as point-of care device. Three different biochip designs (D1, D2 and D3) containing pillars in a microchannel with different bending ratios were conceived and optimized for various mixing param...
Conference Paper
Full-text available
Chalcogenide glasses have wide range of applications in Mid-IR region due to its attractive optical properties. In this paper, we study the influence of UV light on the optical properties of solution based A 2 S 3 chalcogenide thin films by examining transmission spectraand further we compare optical properties of photo annealed solution based thin...
Article
Full-text available
Selective detection and quantification of biomarkers related to human diseases are essential for preventive healthcare. Surface-enhanced Raman scattering (SERS) spectroscopy is a powerful analytical tool offering high sensitivity. However, the success of this promising analytical tool relies on the ability to effectively fabricate SERS substrate. H...
Article
Full-text available
A simple in-situ one-step silver mirror reaction (SMR) was utilized for the growth of silver nanostructures (AgNS) on filter paper (P1,0.01; P2,0.1; and P3,0.2M AgNO 3) for SERS substrates. Concentration dependent growth of AgNS, with the evolution of multifaceted structures have been achieved. Further, SERS substrates were employed to detect Methy...
Article
Chalcogenide Glasses (ChGs) are technologically promising materials widely used in different optical, electronic and optoelectronic applications. Solution processing of ChGs has provided a pathway for less complex thin film processing of these materials and their integration into flexible devices. This paper reviews the basic science behind the sol...
Article
In this paper we report the synthesis and characterization of PVA/Ge10As40Se50 chalcogenide glass nanocomposites free standing films. Ge10As40Se50 nanoparticles are incorporated in PVA matrix via solution processing. From the structural characterization, it is revealed that hydrogen bonding is established between Ge10As40Se50 nanoparticles and PVA...
Chapter
Full-text available
Present work demonstrates an experimental approach to evaluate the optical performance of the Infrared (IR) microlens based on the Shack-Hartmann wavefront sensing at 10.6 µm wavelength. A Germanium microlens has been evaluated to validate the consistency and accuracy of the developed experimental methodology. The proposed IR optical setup has the...
Article
We demonstrate the detection of dipicolinic acid, (DPA), a biomarker of bacterial spores for Bacillus anthracis, 2,4-Dinitrotoluene (DNT) and picric acid (PA) nitroaromatic hazardous chemicals on ultra-sensitive, reusable femtosecond laser textured Au nanostructures decorated with hierarchical AuNPs as a SERS substrate. The AuNPs were achieved by a...
Article
Utilization of Solar Photovoltaic (PV) cells underwater can mitigate the lack of enduring renewable energy sources in marine environments. In our recent studies, the performance of different commercially available silicon Solar cells have been analysed using Xenon Lamp Solar simulator at shallow depths up to 20 cm and the effect of the variation in...
Conference Paper
Solar Photovoltaics have the ability to solve the power requirements that are being faced by various underwater power systems. Although, there are many challenges and constraints, yet the amount of power required for the sensors to monitor and surveillance the water in the ocean, rivers, lakes, etc., can be addressed by underwater Solar In this wor...
Article
Full-text available
Flexible and free-standing polymeric fibers, when coupled with the presence of metal nanoparticles, present an excellent opportunity for sensitive Surface-enhanced Raman Scattering (SERS) Spectroscopy-based detection platforms. Such host matrices are prepared by only a few preferred methods, followed by induction of metal nanoparticle aggregation i...
Article
Underwater photovoltaic (PV) systems supported with modern-day technology can lead to possible solutions for the lack of long-term power sources in marine electronics , navy corps, and many other remotely operated underwater power systems. Currently, most of these systems are powered by conventional batteries, which are bulky, costly, and require p...
Article
Harvesting underwater Solar energy using photovoltaic (PV) technology leads to an innovative approach to utilize it in monitoring various underwater sensors, devices, or other autonomous systems using modern‐day power electronics. Another huge advantage of placing PV cells underwater comes from the fact that the water itself can provide cooling and...
Article
In the present paper, we report the effect of annealing temperature on optical properties of solution processed As2S3 Chalcogenide Glass (ChG) films. Solution processing of ChG films is a low cost, low temperature, scalable route for deposition of high quality films. Annealing of solution processed ChG films is a crucial step for the removal of res...
Article
Exploring the underwater solar energy by solar photovoltaic (PV) cells leads to a huge advantage by utilizing the humongous space of water covered by the earth's surface. Even though the amount of solar radiation decreases with the depth of the water, water provides sustainable cooling and cleaning for solar PV cells underwater. There are many chal...
Article
Most of Solar Photovoltaic (PV) cells are limited to space, dryland and rooftop applications leading to huge scope in exploring the performance of PV cells in an underwater environment. Such underwater Solar energy has tremendous potential to be used in many commercial and defense applications like sensors, underwater vehicles, autonomous power sys...
Article
This paper presents a simple, novel and cost effective process to synthesize MWCNTs and α-Fe2O3 embedded in rGO sheet layers, which is found to be a highly selective and sensitive material for the detection of chloroform vapours in room temperature conditions. The nanocomposite rGO- MWCNT- α-Fe2O3 has showed enhanced chloroform vapour sensing perfo...
Conference Paper
In this paper we report the synthesis and characterization of as-deposited nanostructured As40Se60 chalcogenide glass films via thermal evaporation technique. The morphological investigation of the films reveals that the film is made up nanosized grains. A blueshift is also observed in the optical band-gap of the film which can be attributed to for...
Article
Thin film solar cells with ITO/ZnO/P3HT:PCM:CTSe NCs/Ag structure were fabricated employing a fast and cost-effective procedure using blended solution of P3HT:PCBM:CTSe NCs deposited by spin casting, followed by thermal annealing steps. The CTSe NCs are prepared via solvothermal method. An inverted architecture of device with structure ITO/ZnO/P3HT...
Article
The original version of this article unfortunately contains a mistake. The acknowledgement section of the above article is incorrect. The correct acknowledgements are as follows:
Article
Enzymatic biofuel cells (EBFCs) that utilize glucose as fuel in a human body to produce electricity are being explored as promising alternatives to power implantable devices. However, some limitations need to be overcome to render such micro-electronic devices practically applicable. Here, we propose a microfluidic EBFC architecture with electrodes...
Article
Full-text available
This work demonstrates the fabrication of chalcogenide microstructures such as gratings, lenses and needles using a lithographically directed, evaporative self-organization of chalcogenide thin liquid films for the first time. Using a two-step annealing protocol, excess solvent of freshly coated ChG films is eliminated and then the liquid films are...
Article
Full-text available
The present paper deals with the synthesis and characterization of solution processed pure and multiwalled carbon nanotubes (MWCNTs) incorporated As2S3 glass films. As2S3 glass has been synthesized using melt quenching technique. The solutions of pure and MWCNTs containing As2S3 glass have been prepared in n-butylamine under inert atmosphere. These...
Article
Full-text available
In this paper we report the composite of nanotubular polyaniline (PANI), titanium and iron for microwave absorption. Nanotubular structure of PANI is synthesized by the chemical polymerization of aniline. The diameter of the PANI (Nanotubular) is found to be ranging from 120–140 nm. Here in our experiment we observed resonance-antiresonance phenome...
Article
Full-text available
PPy/TiO2(np)/CNT nanocomposites are synthesized by ‘chemical oxidative polymerization’ of pyrrole. It is observed that polypyrrole along with TiO2(np) form core shell structure. The microwave measurements such as permittivity, permeability and reflection losses (metal back) are studied at X-band. Minimum reflection loss of microwave is due to diele...
Article
Research in Enzymatic Biofuel cells (EBFCs) has evolved during the last decade. However, challenges, such as cost and endurance are the bottlenecks in harnessing their commercialization potential. To overcome these challenges, low cost, readily available pencil leads of various grades modified with polyaniline (PANI) and multi walled carbon nano tu...
Article
We demonstrate the fabrication and nonlinear optical (NLO) characterization of chalcogenide glass thin films obtained from the solution phase driven approach. The characterization of the films was ahieved using FESEM, AFM, micro-Raman, FTIR, UV-Visible spectroscopy, optical profilometry and XRD. The NLO studies were performed on the solution driven...
Article
The SrS: Ce³⁺ thin film active phosphor layer of different thickness based alternating current thin-film electroluminescent (ACTFEL) devices are fabricated by electron beam evaporation deposition (EBED) method. The morphology and chemical composition of the deposited films are investigated by field emission scanning electron microscopy (FESEM). The...
Article
Full-text available
The present paper reports the steady state photoconductivity and photosensitivity response of thermally evaporated amorphous thin films of Se90Sb10-xAgx(x = 2, 4, 6, 8, 10). Temperature dependence of dark conductivity is studied and activation energy is calculated for different samples. Temperature dependence of photoconductivity is also studied at...
Article
Full-text available
We report design, fabrication and characterization of molded chalcogenide microlens array for Infrared sensing applications. A master of desired microlens array with high sag value is prepared using ultraviolet lithography and thermal reflow method on a positive photoresist (ma–P1275HV). The negative replica of the master is created using polydimet...
Conference Paper
Chalcogenide (ChG) are the choice materials for IR applications due to their high refractive index, mid IR transparency and high nonlinear optical properties. In this work, we study the characteristics of solution processed Chalcogenide films, As2S3 prepared by various amine solvents, for possible pattern fabrications. Since solution processed ChG...
Conference Paper
An attempt is made to investigate light induced defects (LID) in amorphous chalcogenide Se90Ag10 thin films prepared by vacuum evaporation technique. For the determination of light induced defects quantitatively, space charge limited current (SCLC) measurements have been made in a vacuum ~ 10−3 Torr before and after exposing amorphous films to whit...
Poster
Enzymatic Bio Fuel Cell (EBFC) utilizes organic molecules as fuel to generate electricity with high efficiency by leveraging enzymes to catalyse redox reactions. Replacing traditional noble metal based catalyst with biocatalysts has several advantages. In our previous work, where we fabricated two types of cost-effective MWCNT coated bio-electrodes...
Article
An attempt is made to observe light induced defects (LID) in amorphous chalcogenides Se90X10 (X = Sb, In, Ag) thin films prepared by vacuum evaporation technique. For the determination of light induced defects quantitatively, space charge limited current (SCLC) measurements have been made in a vacuum ∼10-3 Torr before and after exposing amorphous f...
Conference Paper
In this report, we describe the solution preparation conditions of various chalcogenide glasses. The dissolution mechanism of (As2S3)60 Ge 40, (As2S3)60Se40 in ethanolamine is studied. Dynamic light scattering (DLS)measurements confirms that the particles in suspension are <10 nm in all the solutions.Prepared solutions are shown to possess similar...
Article
In the present work, two types of cost-effective bio-electrodes were fabricated by immobilizing Laccase on commercially available pencil graphite leads, and their electro catalytic activity have been examined. The first type of electrode (E1) was fabricated by electro polymerization of polyaniline on pencil graphite leads on which multi walled carb...
Article
In the present work, two types of cost-effective bio-electrodes were fabricated by immobilizing Laccase on commercially available pencil graphite leads, and their electro catalytic activity have been examined. The first type of electrode (E1) was fabricated by electro polymerization of polyaniline on pencil graphite leads on which multi walled carb...
Article
The structural, optical and electrical properties of pure and tin (Sn) doped zinc oxide (ZnO) nanocrystalline materials prepared by co-precipitation method have been studied as a function of Sn doping concentration. The phase identification through powder X-ray diffraction methods confirmed that pure and Sn-doped zinc oxide powder have typical hexa...
Article
Enzymatic biofuel cell (EBFC) is envisioned as a viable replacement of batteries to work as a power feeding source for self-powered devices and small-scale sensors. In order to be a viable power feeding device, an EBFC should have a higher power output and needs to be miniaturized for its integration into the existing micro-devices, thus making mic...
Article
The present paper reports the comparative study of density of defect states (DOS) between bulk samples and thin films of glassy Se90Sb10. These glasses have been prepared by the quenching technique. Thin films of these glasses have been prepared by vacuum evaporation technique. Space-charge-limited conduction (SCLC) has been measured at different t...
Article
Fuel cell is an efficient energy conversion device converting chemical energy directly into electrical energy. It is a fact that, to boost the fuel cell performance, resistance (charge transfer resistance, mass transfer resistance and electrolyte resistance) should be decreased. For this, many techniques have been used for cell testing such as: cyc...
Article
Nanocrystalline neodymium iron oxide (NdFeO3) has been synthesized through sonication assisted precipitation technique. X-ray diffraction analysis reveals the formation of NdFeO3 having orthorhombic structure (perovskite type). The minimum crystallite size was found 12 nm. Energy dispersive X-ray analysis confirms the elemental compositions of the...
Article
The ability to use chalcogenide glass thin films as photoresists for one-step maskless grayscale lithographic patterning is demonstrated. It is shown that the chalcogenide photoresists can be used to fabricate grayscale patterns with smooth and continuous profiles such as arrays of cylindrical and spherical microlenses, which are useful as optical...
Article
Nanocrystalline neodymium iron oxide (NdFeO3) has been synthesized through sonication assisted precipitation technique. X-ray diffraction analysis reveals the formation of NdFeO3 having orthorhombic structure (perovskite type). The minimum crystallite size was found 12 nm. Energy dispersive X-ray analysis confirms the elemental compositions of the...
Article
Synthesis of a copper ferrite system (CuFe2O4) via chemical co-precipitation method is characterized by X-ray diffraction, surface morphology (scanning electron microscope) and optical absorption spectroscopy. These characteristics show their dependence on the relative compositions of the two subsystems. They are further confirmed by the variation...
Article
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Article
In this paper we report the synthesis of iron-antimonate (FeSbO 4) via co-precipitation method for the LPG sensing application. X-ray diffraction (XRD), Scanning electron microscopy (SEM) and Energy dispersive X-ray analysis (EDAX) were used to confirm the crystal structure, crystallite size, surface morphology and elemental composition of the sens...
Article
Full-text available
Ability to use chalcogenide glass thin films as photoresists for one step gray scale lithography is demonstrated. It is shown that the chalcogenide photoresists can be used to fabricate gray scale patterns such as array of microlens, which can find their application in IR optics. The direct application of the patterned resisits reduces the cost and...
Article
We propose a novel and simplified method to fabricate complex 3-dimensional structures in SU-8 photoresist using maskless grayscale lithography. The proposed method uses a Digital Micro-mirror Device (DMD®) to modulate the light intensity across a single SU-8 photoresist layer. Top and back-side exposure are implemented in the fabrication of origin...
Article
Nanocrystalline (Mg–Zn–Ti) oxide films were deposited on an equilateral prism using sol–gel spin process and then annealed at 450°C for 4h. The humidity sensing properties of the films were investigated at different angles of incidence. It was observed that the intensity of reflected light increased with an increase in relative humidity (%RH) in th...
Conference Paper
We report omnidirectional reflectors with fundamental stop bands in the near infrared, fabricated from polymers and chalcogenide glasses. Thin film stacks exhibit good planarity and adhesion. Optical properties are in good agreement with theoretical predictions.
Article
Full-text available
We have fabricated and tested planar reflectors exhibiting an omnidirectional stop band centered near 1750 nm wavelength. The reflectors are comprised of multiple layers of Ge33As12Se55 chalcogenide glass and polyamide-imide polymer. Glass layers were deposited by thermal evaporation and polymer layers were deposited by spin-casting. Thin film stac...
Article
Erbium doped Ge–Ga–Se thin films were fabricated by the pulsed laser deposition (PLD) technique in vacuum using a KrF pulse laser with λ=248nm, and a pulse duration of 15ns. The films were fabricated at room temperature onto glass substrates. The morphological, optical and thermal properties of the films showed good optical and thermal stability. T...
Article
Full-text available
We review various properties of chalcogenide glasses that make them promising materials for passive and active microphotonics. We then describe two processes for channel waveguide fabrication, using the chalcogenide glass As<sub>2</sub>Se<sub>3</sub> as a core material and compatible polymers as claddings. In the first approach, waveguides are patt...
Article
Chalcogenide glasses have been extensively studied as host media for rare-earth (RE) doped photonic devices due to potential application as optical amplifiers for optical telecommunication. However, fabrication of RE doped homogeneous thin films of chalcogenide glass systems is a difficult task. Doping high amounts of RE atoms (1 to 2 at%) using co...
Article
Full-text available
Low-loss shallow-rib waveguides were fabricated using As2Se3 chalcogenide glass and polyamide-imide polymer. Waveguides were patterned directly in the As2Se3 layer by photodarkening followed by selective wet etching. Theory predicted a modal effective area of 3.5-4 microm2, and this was supported by near-field modal measurements. The Fabry-Perot te...
Article
Shallow rib waveguides were fabricated in arsenic-triselenide chalcogenide glass by direct patterning with ultra-violet light. The Fabry-Perot method was used to measure the propagation loss. Preliminary characterization of holographically defined embedded Bragg gratings is presented.
Article
Full-text available
Photodarkening of thermally evaporated amorphous As2Se3 chalcogenide thin films was generated by a UV mercury light source in a standard mask aligner. The refractive index modification of the chalcogenide glass was determined by applying Swanepoel's method. Index changes of +0.04 were obtained for 500 s exposure. Using these photoinduced index chan...
Article
Films of a-Ge20Se80 prepared by vacuum evaporation, are exposed to visible light and irradiated with 1 MeV Krypton ions. The changes in bonding configurations are studied by Raman spectroscopy. Three bands are observed in the virgin films and are identified as corresponding to the stretching mode of GeSe4/2 corner-sharing tetrahedra (201 cm−1) and...
Article
The present paper reports the effect of illumination on the crystallization kinetics in amorphous Se80–xTe20Inx (0x10). The crystallization was monitored by measuring the electrical conductivity of isothermally annealed samples held at temperatures near the crystallization temperature. It is observed that the crystallization becomes faster in the p...
Article
Isothermal phase transformation of a-Se70Te30-xSbx (0 less than or equal to x less than or equal to 8) in presence and absence of light illumination has been carried out at various temperatures (T-g < T < T-m). The method of change in electrical conductivity has been applied to investigate the effect of illumination on the crystallization of the ab...
Article
Summary Crystallization kinetics is studied in glassy Ge22Se78−x Bi x (0≤x≤10) using isothermal annealing at various temperatures between the glass transition and melting. D.c. conductivity is taken as a parameter to estimate the extent of crystallization (α). The activation energy of crystallization (ΔE) and the order parameter (n) are calculated...
Article
Isothermal phase transformation of a-Se70Te30 − xSbx (0 ⩽ x ⩽ 8) is presence and absence of light illumination has been carried out at various temperatures (Tg < T < Tm). The method of change in electrical conductivity has been applied to investigate the effect of illumination on the crystallization of the above glassy alloys. It has been observed...
Article
Summary The present paper reports a study of photocrystallization in a-Se70Te30−xCdx films (0≤x≤4). The photocrystallization is achieved by shining white light at room temperature for different exposure times. The results indicate that the photocrystallization is suppressed on addition of Cd in binary Se70Te30 system. This is explained in terms of...
Article
Steady-state and transient photoconductivity is studied in amorphous thin films of Se70Te30-xCdx (0&els;x&els;8) with the purpose to see the effect of Cd incorporation in binary Se70Te30 glassy alloys. The results indicate that photoconductivity is highly composition dependent in this system. A discontinuity in various electrical parameters is obse...