Gilbert Daniel Nessim

• PhD MIT; MBA INSEAD; MSEE Politecnico di Milano; MSc Ecole Centrale Paris
• Professor (Full) at Bar Ilan University

Electroconductive textiles (e-Textiles) are vital in developing wearable sensors that preserve the comfort and characteristics of textiles. Among two-dimensional (2D) transition metal dichalcogenides (TMDs), considered a promising option for sensor applications, tungsten di-selenide (WSe2) homostructures have been used as humidity- and temperature-...

Developing high performance catalysts for electrochemical water splitting is critical to an efficient and sustainable route for hydrogen production. For this, single-atom catalysts (SACs) are the best candidates as they offer the highest atom efficiency. However, current methods to produce SACs require a complex synthesis, frequently involving mult...

A new field of two-dimensional (2D) physics has been opened by 2D atomic crystals represented by graphene in recent years. Despite a relatively short research history, the exceptional electrical and optical characteristics of 2D semiconductors make them highly attractive for electronic and optoelectronic purposes. The electronic and optical propert...

Malaria is a major public health concern with over 200 million new cases annually, resulting in significant financial costs. Preventive measures and diagnostic remedies are crucial in saving lives from malaria, and especially in developing nations. 2D materials are, therefore, ideal for fighting such an epidemic. Graphene and its derivatives are ex...

The high concentration of antibiotics in aquatic environments is a serious environmental issue. In response, researchers have explored photocatalytic degradation as a potential solution. Through chemical vapor deposition (CVD), we synthesized copper selenide (β-Cu2−xSe) and found it an effective catalyst for degrading tetracycline hydrochloride (TC...

The electrocatalytic oxygen evolution reaction (OER) is an arduous step in water splitting due to its slow reaction rate and large overpotential. Herein, we synthesized glycerate-anion-intercalated nickel–iron glycerates (NiFeGs) using a one-step solvothermal reaction. We designed various NiFeGs by tuning the molar ratio between Ni and Fe to obtain...

Layered transition metal dichalcogenides (TMDCs) are considered among the next-generation materials for gas sensing. Here, we report exfoliated 2H-WS2 nanosheets for the fabrication of highly performing NO2 sensors. Thermal annealing at several temperatures was performed to investigate the oxidation of WS2. The long-term stability of 2H-WS2 bulk wa...

The use of piezoelectric nanomaterials combined with ultrasound stimulation is emerging as a promising approach for wirelessly triggering the regeneration of different tissue types. However, it has never been explored for boosting chondrogenesis. Furthermore, the ultrasound stimulation parameters used are often not adequately controlled. In this st...

Raman spectroscopy in Transition Metal Dichalcogenides (TMDCs) helps determine their structural information and layer dependency. Because it is non-destructive and fast, it is an archetypal spectroscopic technique to investigate the structure and defects in TMDCs. In our earlier study, we used a metal-dielectric coating to enhance the Raman signal...

Two-dimensional (2D) semiconducting heterojunction chemical sensors are in high demand because of their enhanced response, stability, and selectivity. However, fine-tuning heterojunctions using vapor deposition growth still needs further research. Our present study focuses on the ambient pressure chemical vapor deposition (CVD) synthesis of hexagon...

Although direct methanol fuel cells (DMFCs) have been spotlighted in the past decade, their commercialization has been hampered by the poor efficiency of the methanol oxidation reaction (MOR) due to the unsatisfactory performance of currently available electrocatalysts. Herein, we developed a binder-free, copper-based, self-supported electrode cons...

Low-wavenumber Raman (LWR) Spectroscopy determines signatures in structural information and layer-to-layer dependency of transition metal di-dichalcogenides (TMDCs). It supports proper 2D TMDC analysis and subsequent layer verification. The non-destructive nature and ultra-fast detection make LWR measurements imperative for layer variations and def...

Osteoarthritis implies a progressive degeneration of the whole joint. Cartilage is particularly affected, with inflammation playing a pivotal role1. In recent years, cartilage regeneration has been pursued through several bioengineering strategies and using different stem cell types2-6. Adipose -derived mesenchymal stromal cells (ASCs) constitute a...

Copper chalcogenides are materials characterized by intrinsic doping properties, allowing them to display high carrier concentrations due to their defect‐heavy structures, independent of the preparation method. Such high doping enables these materials to display plasmonic resonances, tunable by varying their stoichiometry. Here, plasmonic dynamics...

The SnS allotrope of tin sulfide can be beneficial for various multifunctional device applications, but its synthesis is a rather challenging task, sometimes requiring the use of toxic materials. In this work, we propose a simple and rapid method to synthesize bulk SnS. We synthesized our material by heating Sn foil with S gas originating from the...

Here, we report a simple route of synthesizing bulk layered TiS2 via chemical vapor transport (CVT) using non-toxic inorganic precursors, followed by successful isolation of few-layered TiS2 flakes using high-frequency-based liquid-phase exfoliation. Exfoliated TiS2 flakes exhibit significantly enhanced photocatalytic activity towards the degradati...

Developing high performance, cost-effective, and durable electrocatalysts that must be derived from non-noble metals is crucial for alkaline oxygen evolution reaction (OER). OER, which takes place at the anode, is accepted as a major obstacle for commercialization due to its sluggish kinetics. In this study, a two-step synthesis method, such as a h...

Tailoring the precise construction of non‐precious metals and carbon‐based heterogeneous catalysts for electrochemical oxygen evolution reaction (OER) and methanol oxidation reaction (MOR) is crucial for energy conversion applications. Herein, this work reports the composite of Ni doped Fe2O3 (Ni−Fe2O3) with mildly oxidized multi‐walled CNT (O−CNT)...

With high power consumption and energy densities in demand, there has been a surge in researching the next-generation electrochemical energy storage devices (lithium-ion batteries, sodium-ion batteries, and magnesium-ion batteries). 2D layered transition metal selenides (TMSes) are promising in terms of scalability and portability for electronic de...

Transition-metal dichalcogenides (TMDCs) are unique layered materials with exotic properties. So, examining their structures holds tremendous importance. 2H-MoSe2 (analogous to MoS2; Gr. 6 TMDC) is a crucial optoelectronic material studied extensively using Raman spectroscopy. In this regard, low-frequency Raman (LFR) spectroscopy can probe this ma...

Similarly to other transition metal sulfides, nickel sulfide nanocrystals can be potentially used for functional device applications. However, controlling morphology and stoichiometry to target specific applications is a synthesis challenge. In this work we developed a rapid, one-step, chemical vapor deposition synthesis of nickel sulfide dendritic...

Transition-metal di-chalcogenides (TMDCs) are van der Waals (vdW) layered materials with unique properties, important for the semiconductor industry. Generally, MX2 (where M = metal and X = chalcogen atoms, such as S, Se, or Te) type TMDCs contain easily exfoliable layers, turning to essentially 2D materials. Planar structural defects, such as stac...

Correction for ‘Thiadiazole containing N- and S-rich highly ordered periodic mesoporous organosilica for efficient removal of Hg(II) from polluted water’ by Asim Baumik et al. , Chem. Commun. , 2020, 56 , 3963–3966, DOI 10.1039/D0CC00407C.

MXenes are a large class of 2D materials that consist of few‐atoms‐thick layers of transition metal carbides, nitrides, or carbonitrides. The surface functionalization of MXenes has immense implications for their physical, chemical, and electronic properties. However, solution‐phase surface functionalization often leads to structural degradation of...

Recently, graphene and its derivatives have been extensively investigated for their interesting properties in many biomedical fields, including tissue engineering and regenerative medicine. Nonetheless, graphene oxide (GO) and reduced GO (rGO) are still under investigation for improving their dispersibility in aqueous solutions and their safety in...

In article number 2001434 by Leonardo Ricotti, Gina Lisignoli, Diego Trucco, and co‐workers, a bilayered hydrogel made of gellan gum and poly(ethylene glycol)diacrylate fills chondral defects of articular knee cartilage, mimicking the superficial and the deep zones in terms of mechanical and lubrication features. Graphene oxide dopant improves the...

Among the most reliable techniques for exfoliation of two-dimensional (2D) layered materials, sonication-assisted liquid-phase exfoliation (LPE) is considered as a cost-effective and straightforward method for preparing graphene and its 2D inorganic counterparts at reasonable sizes and acceptable levels of defects. Although there were rapid advance...

Articular cartilage (AC) is a specialized connective tissue able to provide a low‐friction gliding surface supporting shock‐absorption, reducing stresses, and guaranteeing wear‐resistance thanks to its structure and mechanical and lubrication properties. Being an avascular tissue, AC has a limited ability to heal defects. Nowadays, conventional str...

This paper aims to characterize the wear behavior of hydrogel constructs designed for human articular cartilage replacement. To this purpose, poly (ethylene glycol) diacrylate (PEGDA) 10% w/v and gellan gum (GG) 1.5% w/v were used to reproduce the superior (SUP) cartilage layer and PEGDA 15% w/v and GG 1.5% w/v were used to reproduce the deep (DEEP...

We report a facile and robust room-temperature NO2 sensor fabricated using bi- and multi-layered 2H variant of tungsten di-selenide (2H-WSe2) nanosheets, exhibiting high sensing characteristics. A simple liquid-assisted exfoliation of 2H-WSe2, prepared using ambient pressure chemical vapor deposition, allows smooth integration of these nanosheets o...

Here, we report a facile upscaled ambient pressure CVD-assisted synthesis of low-temperature phase silver selenide (β-Ag2Se) on Ag foil and its first-reported application (in its pristine form) as an ORR catalyst. The exfoliated β-Ag2Se via XRD, EDS, HRTEM, AFM, and HRSEM determines its stoichiometry and its hollow layered fern-like morphology. Dif...

In this article, the limits of thin-film deposition on very rough topographies are demonstrated by depositing alumina on vertically aligned carbon nanotubes (VACNTs). Vapor deposition techniques are the enabling platforms of the thin-film industry, offering high material versatility and good coverage ability on relatively flat surfaces, leading to...

We designed a heterostructure of Fe 3 S 4 @ Ni 3 S 2 , as a potent oxygen evolution reaction (OER) electrocatalyst in an alkaline medium. Intriguingly, Fe 3 S 4 @ Ni 3 S 2 exhibits low onset potential of 290 mV and overpotential of 360 mV at a current density of 10 mA cm ‐2 . We examined the OER kinetics of Fe 3 S 4 @ Ni 3 S 2 using distribution fu...

Exploring and identifying efficient materials with operative active sites for electrochemical oxygen evolution reaction (OER) is of paramount importance for the future of energy conversion technologies like electrolyzers and fuel cells. Herein, we develop an effective strategy to couple physically distinct metal-rich nickel phosphide (Ni12P5) with...

Hypothesis: From the end of the twentieth century, the growing interest in a new generation of wearable electronics with attractive application for military, medical and smart textiles fields has led to a wide investigation of chemical finishes for the production of electronic textiles (e-textiles). Experiments: Herein, a novel method to turn in...

Carbon nanomaterials have been introduced as a scaffold for various biological applications due to their unique physical and electrical properties. Here we studied carbon nanotubes (CNTs) and carbon nanofibers (CNFs) as scaffold materials for the differentiation of human embryonic stem cells (hESCs) towards photoreceptor precursor cells (PRPs). We...

Here we show a facile two-furnace AP-CVD synthesis of 2H-WSe2 using W foil and elemental Se as precursors in Ar atmosphere. Systematic refinement of the process parameters and exhaustive characterization of the bulk and exfoliated material confirm that 2H-WSe2 is a 2D layered material suitable for LiB applications.

We report a facile two-furnace APCVD synthesis of 2H-WSe2. A systematic study of the process parameters is performed to show the formation of the phase-pure material. Extensive characterization of the bulk and exfoliated material confirm that 2H-WSe2 is layered (i.e., 2D). X-ray diffraction (XRD) confirms the phase, while high-resolution scanning e...

Transition metal phosphides already emerged with great interest due to their energy storage capacitance, superior metalloid characteristics, and decent electrical conductivity. To achieve a commercially viable outcome, these electrodes are fabricated with interconnected carbonaceous materials. Herein, we have synthesized hexagonal copper phosphide...

Hard carbon (HC) has emerged as potential anode material for sodium-ion batteries (SIB). However, it is plagued with several issues like low capacity, poor cyclability, significant electrolyte degradation on interface. Realization of HC as anode requires fundamental understanding of the effect of its porous structure/composition on electrochemical...

A new N- and S-rich highly ordered periodic mesoporous organosilica material DMTZ-PMO bearing thaidiazole and thiol moieties inside the pore-wall of 2D-hexagonal nanomaterial has been synthesized. DMTZ-PMO showed very high...

Direct methanol fuel cells (DMFCs) represent a class of fuel cells that can be categorized under low temperature–operating proton exchange membrane (PEM) fuel cells. These PEM electrolytes are mostly made from polymers; thus they are also termed “polymer electrolyte membranes.” The basic function of a DMFC is to generate electrical energy by cataly...

Electrochemical water splitting, which generates both hydrogen and oxygen, using highly efficient and low‐cost noble metal‐free (Pt, Ru, Ir etc.) electrocatalyst is an economical and green approach for the alternative energy source. Due to their conductivity, durability and long‐term stability, carbonaceous containing hybrid materials are used as p...

In this paper, a new and versatile approach to obtain a good dispersion in water-based paste of short (≅ 1.5 mm) and long (≅ 3.0 mm) millimeter-sized carbon nanotubes (CNT) for the fabrication of electroconductive textiles is reported. With this aim, N-[3-(triethoxysilyl)propyl]ethylenediamine (EDAES) was used in combination with a waterborne therm...

In this work, siliceous breccia, a natural rock powder composed essentially of SiO2 α-quartz, has been employed directly as a catalyst without any chemical treatment for the synthesis of carbon nanotubes (CNTs) via chemical vapor deposition (CVD). In addition to quartz, it contains dispersed micro-inclusions of iron oxide-hydroxides, goethite or he...

We have studied the magnetization of a recently synthesized Cu 9S 5 compound and found two phase transitions around room temperature. The phase transitions in the crystalline structure, characterized by XRD studies, are accompanied by changes also in the electrical resistivity. A hysteretic first-order phase transition has been found between 260 an...

Many catalyst materials have been tried to synthesize ultra-long carbon nanotubes (CNTs) by extending catalyst lifetime and delaying growth termination. We propose a time-controlled, variable composition iron-molybdenum catalyst system, where the diffusion of molybdenum (as a thin layer reservoir) is mediated by the alumina underlayer, to reach and...

One of the bottlenecks towards the successful implementation of alternative energies is the lack of methods for sustainable generation of hydrogen fuel as an energy carrier. Given that water will be at the very least an important component of the hydrogen production feedstock, sustainable catalysts are needed for the electrochemical generation of h...

Carbon nanotubes exhibit mechanical properties ideally suited for reinforced structural composites and surface area and conductivity attractive for electrochemical capacitors. Here we demonstrate the multifunctional synergy between these properties in a composite material exhibiting simultaneous mechanical and energy storage properties. This involv...

Here we demonstrate a composite material exhibiting dual multifunctional properties of a structural material and a redox-active battery. This incorporates three-dimensional aligned carbon nanotube interfaces that weave together a structural frame, redox-active battery materials, and a Kevlar-infiltrated solid electrolyte that facilitates ion transf...

Carbon nanotubes (CNTs), the closest structure to ideal one-dimensional (1D) conductors, have stimulated substantial interest in the last decades for many applications in the field of nanotechnology. Unfortunately, the high cost of efficient metal catalysts limits the large-scale exploitation of carbon nanomaterials synthesis processed by chemical...

Lithography and lift-off of the catalyst is the established way to pattern forests of carbon nanotubes (CNTs). We demonstrate an alternative technique where we pattern a thin film reservoir residing below the Al2O3 underlayer to partially or fully deactivate the iron catalyst on the surface, thus leading to short CNTs or no CNTs. High-resolution im...

The correlation between MWCNT aspect ratio and the quasi-static and dynamic mechanical properties of composites of MWCNTs and PMMA was studied for relatively long MWCNT lengths, in the range 0.3 mm to 5 mm (aspect ratios up to 5 ×10⁵) and at low loading (0.15 wt%). The height of the MWCNTs prepared were modulated by controlling the amount of water...

Black phosphorus (BP) is a layered semiconductor with outstanding properties, making it a promising candidate for optoelectronic and other applications. BP synthesis is an intriguing task, largely due to the insufficient understanding of the synthesis mechanism. In this work, we use density functional theory calculations to examine BP, and its prec...

Most of the recently discovered layered materials such as MoS2, or MoSe2 are n-type, while few materials, such as phosphorene, which suffers from rapid oxidation, are p-type. To form devices such as p-n junctions and heterojunctions, new p-type mono/few layers are needed. Here, we report a one-step synthesis of layered, crystalline, p-type copper s...

We present a simple, environment-friendly, and fast synthesis of nitrogen-doped graphene quantum dots (N-GQDs) on copper foil by chemical vapor deposition using exclusively chitosan, a cheap and non-toxic biopolymer, as a carbon and nitrogen precursor. We characterized the synthesized N-doped graphene quantum dots using Raman spectroscopy, XPS, AFM...

Interactions of vertically aligned multiwall carbon nanotubes (CNTs) with high energy He⁺ beams were studied using elastic recoil detection analysis and ion beam channeling. The relationship between the elastic recoil of hydrogen, the depth of He–H interactions, and the number of carbon atoms per volume (denoted as effective density) was calculated...

Using chemical vapor deposition, we grew carbon nanotubes (CNTs) on the surface of Si nanoparticles (NPs) that were coated with a thin iron shell. We studied the CNT growth mechanisms and analyzed the influence of (1) varying annealing times, and (2) varying growth times. We show that an initial annealing is necessary to reduce the iron oxide shell...

Inducing porosity in solid coordination complex crystals, which are an important class of catalysts, is critical for many applications where a high surface area is required. However, unlike metal organic frameworks (MOFs), fabrication of porous coordination crystals remains a significant challenge. Here we demonstrate a simple method to produce and...

We developed a fast, simple, scalable and safe method for the metal-free reduction and nitrogen-doping of graphene oxide (GO) using volatile nitrogen-containing heterocyclic compounds. In this method, chitosan and graphene oxide were simultaneously annealed without making any physical contact between them under a flow of argon using chemical vapor...

We analyzed the effect of nickel overlayers positioned in close proximity (bridges) or in contact (stencils) with the catalytic layer on the growth of vertically aligned carbon nanotubes (VACNTs) using thermal chemical vapor deposition (CVD). We studied the physical–chemical mechanisms, namely, the interaction of the overlayer with the gases and wi...

Carbon nanotubes (CNT) lie at the crossroads of a multitude of different next generation technologies. Among the most promising of these are structural reinforcement of composites and high energy density supercapacitors. Our work presents a unique approach where CNT grown on stainless steel meshes are used to simultaneously mechanically reinforce a...

The oxidation level and properties of reduced graphene oxides (rGOs) were fine-tuned using temperature programmed reductive annealing. rGOs were -annealed at different temperatures (from 500°C to 1000°C) in hydrogen to modulate their oxidation levels. The surface of the rGOs was fully characterized using Electron Paramagnetic Resonance backed by Ra...

Using a system of multi-zone thermal chemical vapor deposition (CVD) furnaces in parallel and in series, we performed differential preheating of the incoming gases to independently control water vapor formation (from oxygen and hydrogen) and hydrocarbon decomposition to grow vertically aligned multi-wall carbon nanotube (MWCNT) carpets. We identifi...

We show a simple technique to grow patterned carbon nanotube (CNT) forests by annealing the catalytic surface using copper patterns (as stencil or bridge) prior to, or during CNT growth. We demonstrate that copper diffused into the iron catalyst and deactivated it, thus preventing CNT growth on the areas where the copper was present. This technique...

Hybridized polaritons are generated by simultaneously coupling two vibrational modes of two different organic materials to the resonance of a low-loss infrared optical microcavity. A thin film of poly methyl methacrylate with solvent molecules of dimethylformamide trapped inside provided two spectrally narrow, closely spaced carbonyl stretches with...

The number of patients suffering from Inflammatory Bowel Disease (IBD) is increasing worldwide. The development of noninvasive tests that are rapid, sensitive, specific and simple would allow preventing patient discomfort, delay in diagnosis, and the follow-up of the status of the disease. Herein, we show the interest of vertically aligned nitrogen...

We quantified the amount of hydrogen in as-grown vertically aligned multiwall CNTs at different stages of growth using elastic recoil detection analysis (ERDA). We suggest that hydrogen is associated with atomic defects and/or amorphous carbon impurities formed at earlier deposition stages. We found that the highest amount of hydrogen (2.3 wt %) wa...

Microcavity devices exhibiting strong light-matter coupling in the mid-infrared spectral range offer the potential to explore exciting open physical questions pertaining to energy transfer between heat and light and can lead to a new generation of efficient wavelength tunable mid-infrared sources of coherent light based on polariton Bose-Einstein C...

We describe the fabrication and characterization of highly reflecting distributed Bragg reflectors (DBR) composed of thermally evaporated thin films of CaF2 and ZnS without substrate heating. Proposed technique enables DBR deposition on delicate lasing materials.

Carbon nanofibres (CNFs) functionalized with 4-amino-2,6-dimethylpyridine were found to be an efficient metal free catalyst for the synthesis of quinazoline-2,4(1H,3H)-diones from CO2 and 2-aminobenzonitriles using water as a reaction medium. The presence of water they exhibited a remarkable enhancement in reaction rates and provided high to excell...

The magnetotransport properties were studied in hundreds of micrometer length double-wall carbon nanotubes (DWCNT) bundles. Above 15 K the resistance shows an ohmic behavior and its temperature dependence is well described using the variable-range hopping for one-dimensional system. The magnetoresistance is negative and can be explained using an em...

Pyridine functionalized carbon nanofibers (Py-CNFs) were synthesized, characterized and used for the grafting of oxo-rhenium complex i.e. methyltrioxorhenium (MTO) via acid-base ionic interaction. The grafting of MTO to Py-CNFs was confirmed by FTIR, UV-VIS, SEM, TEM and TGA analyses. The determination of rhenium content by ICP-AES further suggeste...

We describe the design, fabrication, and characterization of mechanically stable, reproducible, and highly reflecting distributed Bragg reflectors (DBR) composed of thermally evaporated thin films of calcium fluoride (CaF2) and zinc sulfide (ZnS). CaF2 and ZnS were chosen as the low and high refractive index components of the multilayer DBR structu...

By preheating the precursor gases (ethylene and hydrogen), we synthesized high-quality, few-layer graphene at reduced temperature with full reproducibility on nickel thin films. Raman spectroscopy showed that the graphene films synthetized using gas preheating exhibited 50% less defects compared to those obtained without gas preheating. All experim...

In this manuscript, we report our investigation of anode materials for Li-ion batteries based on silicon–graphene oxide composites. Previous reports in the literature on silicon–graphene oxide (GO) composites as anodes have shown a large discrepancy between the electrochemical properties, mainly capacity and coulombic efficiency. In our research, t...

We synthesized millimeter-tall, dense carpets of crystalline CNTs on nonpolished copper substrates with a thin Al2O3 (below 10 nm) underlayer and Fe (1.2 nm) layer as a catalyst using chemical vapor deposition (CVD). Preheating of the hydrocarbon precursor gases and in-situ formation of controlled amounts of water vapor were critical process parame...

We directly synthesized large self-assembled, conductive, and superhydrophobic three-dimensional mats of entangled carbon nanofibers (CNFs) using thermal chemical vapor deposition (CVD). We show that the yield obtained from the catalysis of an unconstrained thin Ni-Pd film is over an order of magnitude higher compared to the same thin film when bou...

Thin, air-stable, nanogranular iron-based films of 10 ± 1.2, 100 ± 14 and 400 ± 46 nm thicknesses were prepared by Chemical Vapor Deposition (CVD) of triiron dodecacarbonyl, Fe3(CO)12, onto silicon wafers at 150 °C in an inert environment at a standard pressure of 100 kPa. These thin nanogranular structured films, composed of sintered elemental Fe...

Here we demonstrate an approach to enhance the growth of vertically aligned carbon nanotubes (CNTs) by including a catalyst reservoir underneath the thin-film alumina catalyst underlayer. This reservoir led to enhanced CNT growth due to the migration of catalytic material from below the underlayer up to the surface through alumina pinholes during p...

Bidirectional-growth of carbon nanofibers is a rare phenomenon found on free-standing catalyst particles, in contrast to the most commonly studied tip- and base-growth mechanisms for carbon nanostructures synthesized through thermal chemical vapor deposition. We reveal the underlying mechanisms of collective bidirectional growth in NixPd1-x-catalyz...

Lead acid (LA) batteries are an established mature technology mainly used for low energy density applications. Crumbling/sulfation is the main failure mechanism of the active materials, which limits their cycle life. LA batteries possessing long cycle life can serve as an ideal energy storage technology for load leveling applications. By uniformly...

The impact of gas-phase pretreatment of supported iron-oxide catalyst utilized in aligned carbon nanotube (CNT) growth is studied to understand the correlation between the catalyst oxidation state and the growth characteristics of the aligned CNT forests. By varying the pretreatment conditions from a reducing to an oxidizing environment, notable ch...