I am PCCM postdoctoral fellow in Princeton Center for Complex Materials at Princeton University. I received my Ph.D. from Materiaals Science and Nanoengineering department of Rice University. I am skilled in nanomaterials synthesis, for a variety of applications such as catalysis, renewable energy, and sustainability, water treatment, mechanical damping etc. Address: Princeton university, United States
Here we report a unique method to locally determine the mechanical response of individual covalen... more Here we report a unique method to locally determine the mechanical response of individual covalent junctions between carbon nanotubes (CNTs), in various configurations such as "X", "Y" and…
Since its isolation by Geim and coworkers, graphene has received a lot of attention from the rese... more Since its isolation by Geim and coworkers, graphene has received a lot of attention from the research community as well as industry. Interesting and groundbreaking research has been published on graphene showing excellent properties and a wide range of applications. It was thought that graphene could replace well-established applications currently being controlled by graphite. In this perspective, we review large-scale applications of graphite that we think graphene can replace. We also discuss niche applications that we think graphene can make inroads for large-scale applications.
To improve the HER catalyst the role of defects and interface of hetero-structures needs to be un... more To improve the HER catalyst the role of defects and interface of hetero-structures needs to be understood well. In this work, we signified the role of the hBN–CNS interface with possible defects in generating highly active sites for the HER catalysis.
Recent advances and demands in biomedical applications drive a large amount of research to synthe... more Recent advances and demands in biomedical applications drive a large amount of research to synthesize easily scalable low-density, high-strength, and wear-resistant biomaterials. The chemical inertness with low density combined with high strength makes h-BN one of the promising materials for such application. In this work, three-dimensional hexagonal boron nitride (h-BN) interconnected with boron trioxide (BO) was prepared by easily scalable and energy efficient spark plasma sintering (SPS) process. The composite structure shows significant densification (1.6-1.9 g/cm) and high surface area (0.97-14.5 m/g) at an extremely low SPS temperature of 250 °C. A high compressive strength of 291 MPa with a reasonably good wear resistance was obtained for the composite structure. The formation of strong covalent bonds between h-BN and BO was formulated and established by molecular dynamics simulation. The composite showed significant effect on cell viability/proliferation. It shows a high min...
A stable, conductive, additive-free and scalable 3D architecture supercapacitor electrode fabrica... more A stable, conductive, additive-free and scalable 3D architecture supercapacitor electrode fabricated by atomically thin 2D sheets of GO and MoS2 shows superior electrochemical properties which are further substantiated using MD simulations.
3D (three dimensional) architectures synthesised using an easily scalable solid state method whic... more 3D (three dimensional) architectures synthesised using an easily scalable solid state method which results in an interconnected network of porous h-BN sheets with boron trioxide are reported in this study.
Here we report a unique method to locally determine the mechanical response of individual covalen... more Here we report a unique method to locally determine the mechanical response of individual covalent junctions between carbon nanotubes (CNTs), in various configurations such as "X", "Y" and…
Here, we report the scalable synthesis and characterization of low-density, porous, three-dimensi... more Here, we report the scalable synthesis and characterization of low-density, porous, three-dimensional (3D) solids consisting of two-dimensional (2D) hexagonal boron nitride (h-BN) sheets. The structures are synthesized using bottom-up, low-temperature (∼300 °C), solid-state reaction of melamine and boric acid giving rise to porous and mechanically stable interconnected h-BN layers. A layered 3D structure forms due to the formation of h-BN, and significant improvements in the mechanical properties were observed over a range of temperatures, compared to graphene oxide or reduced graphene oxide foams. A theoretical model based on Density Functional Theory (DFT) is proposed for the formation of h-BN architectures. The material shows excellent, recyclable absorption capacity for oils and organic solvents.
A demonstration of the chemical functionalization of h-BN flakes and a template free approach for... more A demonstration of the chemical functionalization of h-BN flakes and a template free approach for the development of macroscopic porous h-BN solids.
Abstract A self-assembled MoSe2 nanolayers/reduced graphene oxide (MoSe2/rGO) foam was prepared u... more Abstract A self-assembled MoSe2 nanolayers/reduced graphene oxide (MoSe2/rGO) foam was prepared using a hydrothermal method. The samples were systematically investigated by X-ray diffraction, field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, and high-resolution transmission electron microscopy. Electrochemical performances were evaluated in two-electrode cells versus metallic lithium. It is demonstrated that the obtained MoSe2/rGO nanocomposites show three-dimensional architecture and excellent electrochemical performance as anode materials for Li-ion batteries. The specific capacity of MoSe2/rGO anode can reach up to 650 mAh g−1 at a current rate of 0.1C in the voltage range 0.01–3.0 V (vs. Li/Li+), which is higher than the theoretical capacity of MoSe2 (422 mAh g−1). Additionally, the fabricated half cells have shown good rate capability and long cycling stability with 10.9% capacity loss after 600 cycles under a current density of 0.5C. The excellent performance of the synthesized MoSe2/rGO is attributed to its unique nanostructure, including nanolayered MoSe2, highly conductive rGO networks and mechanically stable 3D architecture.
Carbon nanotubes can be chemically modified by attaching various functionalities to their surface... more Carbon nanotubes can be chemically modified by attaching various functionalities to their surfaces, although harsh chemical treatments can lead to their break-up into graphene nanostructures. On the other hand, direct coupling between functionalities bound on individual nanotubes could lead to, as yet unexplored, spontaneous chemical reactions. Here we report an ambient mechano-chemical reaction between two varieties of nanotubes, carrying predominantly carboxyl and hydroxyl functionalities, respectively, facilitated by simple mechanical grinding of the reactants. The purely solid-state reaction between the chemically differentiated nanotube species produces condensation products and unzipping of nanotubes due to local energy release, as confirmed by spectroscopic measurements, thermal analysis and molecular dynamic simulations.
Creating ordered microstructures with hydrophobic and hydrophilic moieties that enable the collec... more Creating ordered microstructures with hydrophobic and hydrophilic moieties that enable the collection and storage of small water droplets from the atmosphere, mimicking structures that exist in insects, such as the Stenocara beetle, which live in environments with limited amounts of water. Inspired by this approach, vertically aligned multiwalled carbon nanotube forests (NTFs) are asymmetrically end-functionalized to create hygroscopic scaffolds for water harvesting and storage from atmospheric air. One side of the NTF is made hydrophilic, which captures water from the atmosphere, and the other side is made superhydrophobic, which prevents water from escaping and the forest from collapsing. To understand how water penetrates into the NTF, the fundamentals of water/NTF surface interaction are discussed.
Here we report a unique method to locally determine the mechanical response of individual covalen... more Here we report a unique method to locally determine the mechanical response of individual covalent junctions between carbon nanotubes (CNTs), in various configurations such as "X", "Y" and…
Since its isolation by Geim and coworkers, graphene has received a lot of attention from the rese... more Since its isolation by Geim and coworkers, graphene has received a lot of attention from the research community as well as industry. Interesting and groundbreaking research has been published on graphene showing excellent properties and a wide range of applications. It was thought that graphene could replace well-established applications currently being controlled by graphite. In this perspective, we review large-scale applications of graphite that we think graphene can replace. We also discuss niche applications that we think graphene can make inroads for large-scale applications.
To improve the HER catalyst the role of defects and interface of hetero-structures needs to be un... more To improve the HER catalyst the role of defects and interface of hetero-structures needs to be understood well. In this work, we signified the role of the hBN–CNS interface with possible defects in generating highly active sites for the HER catalysis.
Recent advances and demands in biomedical applications drive a large amount of research to synthe... more Recent advances and demands in biomedical applications drive a large amount of research to synthesize easily scalable low-density, high-strength, and wear-resistant biomaterials. The chemical inertness with low density combined with high strength makes h-BN one of the promising materials for such application. In this work, three-dimensional hexagonal boron nitride (h-BN) interconnected with boron trioxide (BO) was prepared by easily scalable and energy efficient spark plasma sintering (SPS) process. The composite structure shows significant densification (1.6-1.9 g/cm) and high surface area (0.97-14.5 m/g) at an extremely low SPS temperature of 250 °C. A high compressive strength of 291 MPa with a reasonably good wear resistance was obtained for the composite structure. The formation of strong covalent bonds between h-BN and BO was formulated and established by molecular dynamics simulation. The composite showed significant effect on cell viability/proliferation. It shows a high min...
A stable, conductive, additive-free and scalable 3D architecture supercapacitor electrode fabrica... more A stable, conductive, additive-free and scalable 3D architecture supercapacitor electrode fabricated by atomically thin 2D sheets of GO and MoS2 shows superior electrochemical properties which are further substantiated using MD simulations.
3D (three dimensional) architectures synthesised using an easily scalable solid state method whic... more 3D (three dimensional) architectures synthesised using an easily scalable solid state method which results in an interconnected network of porous h-BN sheets with boron trioxide are reported in this study.
Here we report a unique method to locally determine the mechanical response of individual covalen... more Here we report a unique method to locally determine the mechanical response of individual covalent junctions between carbon nanotubes (CNTs), in various configurations such as "X", "Y" and…
Here, we report the scalable synthesis and characterization of low-density, porous, three-dimensi... more Here, we report the scalable synthesis and characterization of low-density, porous, three-dimensional (3D) solids consisting of two-dimensional (2D) hexagonal boron nitride (h-BN) sheets. The structures are synthesized using bottom-up, low-temperature (∼300 °C), solid-state reaction of melamine and boric acid giving rise to porous and mechanically stable interconnected h-BN layers. A layered 3D structure forms due to the formation of h-BN, and significant improvements in the mechanical properties were observed over a range of temperatures, compared to graphene oxide or reduced graphene oxide foams. A theoretical model based on Density Functional Theory (DFT) is proposed for the formation of h-BN architectures. The material shows excellent, recyclable absorption capacity for oils and organic solvents.
A demonstration of the chemical functionalization of h-BN flakes and a template free approach for... more A demonstration of the chemical functionalization of h-BN flakes and a template free approach for the development of macroscopic porous h-BN solids.
Abstract A self-assembled MoSe2 nanolayers/reduced graphene oxide (MoSe2/rGO) foam was prepared u... more Abstract A self-assembled MoSe2 nanolayers/reduced graphene oxide (MoSe2/rGO) foam was prepared using a hydrothermal method. The samples were systematically investigated by X-ray diffraction, field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, and high-resolution transmission electron microscopy. Electrochemical performances were evaluated in two-electrode cells versus metallic lithium. It is demonstrated that the obtained MoSe2/rGO nanocomposites show three-dimensional architecture and excellent electrochemical performance as anode materials for Li-ion batteries. The specific capacity of MoSe2/rGO anode can reach up to 650 mAh g−1 at a current rate of 0.1C in the voltage range 0.01–3.0 V (vs. Li/Li+), which is higher than the theoretical capacity of MoSe2 (422 mAh g−1). Additionally, the fabricated half cells have shown good rate capability and long cycling stability with 10.9% capacity loss after 600 cycles under a current density of 0.5C. The excellent performance of the synthesized MoSe2/rGO is attributed to its unique nanostructure, including nanolayered MoSe2, highly conductive rGO networks and mechanically stable 3D architecture.
Carbon nanotubes can be chemically modified by attaching various functionalities to their surface... more Carbon nanotubes can be chemically modified by attaching various functionalities to their surfaces, although harsh chemical treatments can lead to their break-up into graphene nanostructures. On the other hand, direct coupling between functionalities bound on individual nanotubes could lead to, as yet unexplored, spontaneous chemical reactions. Here we report an ambient mechano-chemical reaction between two varieties of nanotubes, carrying predominantly carboxyl and hydroxyl functionalities, respectively, facilitated by simple mechanical grinding of the reactants. The purely solid-state reaction between the chemically differentiated nanotube species produces condensation products and unzipping of nanotubes due to local energy release, as confirmed by spectroscopic measurements, thermal analysis and molecular dynamic simulations.
Creating ordered microstructures with hydrophobic and hydrophilic moieties that enable the collec... more Creating ordered microstructures with hydrophobic and hydrophilic moieties that enable the collection and storage of small water droplets from the atmosphere, mimicking structures that exist in insects, such as the Stenocara beetle, which live in environments with limited amounts of water. Inspired by this approach, vertically aligned multiwalled carbon nanotube forests (NTFs) are asymmetrically end-functionalized to create hygroscopic scaffolds for water harvesting and storage from atmospheric air. One side of the NTF is made hydrophilic, which captures water from the atmosphere, and the other side is made superhydrophobic, which prevents water from escaping and the forest from collapsing. To understand how water penetrates into the NTF, the fundamentals of water/NTF surface interaction are discussed.
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