Author
Prashant V. Kamat
Other affiliations: Indian Institute of Technology Kanpur, Council of Scientific and Industrial Research, Université du Québec à Trois-Rivières ...read more
Bio: Prashant V. Kamat is an academic researcher from University of Notre Dame. The author has contributed to research in topics: Racism & Excited state. The author has an hindex of 140, co-authored 725 publications receiving 79259 citations. Previous affiliations of Prashant V. Kamat include Indian Institute of Technology Kanpur & Council of Scientific and Industrial Research.
Topics: Racism, Excited state, Electron transfer, Quantum dot, Flash photolysis
Papers published on a yearly basis
Papers
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TL;DR: One-Dimensional (1-D) Transport Architectures 6675 4.2.1.
Abstract: 3.1. Fundamental Characterization 6672 3.2. Photocurrent Action Spectroscopy 6673 3.3. Optical Characterization 6673 3.4. Characterization of Electron Transfer 6673 4. Electron Transport in Metal Oxide Films 6674 4.1. Mechanism of Photoinduced Carrier Transport 6674 4.2. Characterization of Diffusion Length 6675 4.3. One-Dimensional (1-D) Transport Architectures 6675 4.4. Electrolyte Interactions 6676 5. Recent Trends in Liquid-Junction Solar Cells 6676 5.1. Dye Sensitized Solar Cells 6677 5.2. Quantum Dot Sensitized Solar Cells 6678 5.3. Carbon Nanostructure Based Photochemical Solar Cells 6679
714 citations
TL;DR: The methodologies adopted for organizing chromophore-functionalized gold nanoparticles on two-dimensional surfaces and the mechanistic details of various deactivation channels of the photoexcited chromophores, such as energy and electron transfer to the metal nanoparticle, are presented.
Abstract: We report in this Account the design of chromophore-functionalized metal nanoparticles and the detailed investigation of the ground- and excited-state interactions between the metal nanoparticles and the photoactive molecules. The methodologies adopted for organizing chromophore-functionalized gold nanoparticles on two-dimensional surfaces and the mechanistic details of various deactivation channels of the photoexcited chromophores, such as energy and electron transfer to the metal nanoparticle, are presented. The possible applications of such chromophore-functionalized gold nanoparticles in photovoltaics, light-mediated binding and release of biologically important molecules such as amino acid derivatives, and fluorescent display devices are described.
628 citations
TL;DR: The interplay between the TiO2 and SWCNT of attaining charge equilibration is an important factor for improving photoelectrochemical performance of nanostructured semiconductor based solar cells.
Abstract: Single wall carbon nanotube (SWCNT) architecture when employed as conducting scaffolds in a TiO2 semiconductor based photoelectrochemical cell can boost the photoconversion efficiency by a factor of 2. Titanium dioxide nanoparticles were dispersed on SWCNT films to improve photoinduced charge separation and transport of carriers to the collecting electrode surface. The shift of ∼100 mV in apparent Fermi level of the SWCNT−TiO2 system as compared to the unsupported TiO2 system indicates the Fermi level equilibration between the two systems. The interplay between the TiO2 and SWCNT of attaining charge equilibration is an important factor for improving photoelectrochemical performance of nanostructured semiconductor based solar cells. The feasibility of employing a SWCNT−TiO2 composite to drive the water photoelectrolysis reaction has also been explored.
611 citations
TL;DR: Graphene-based assemblies are gaining attention as a viable alternate to boost the efficiency of various catalytic and storage reactions in energy conversion applications as discussed by the authors, and the use of reduced graphene oxide has already proved useful in collecting and transporting charge in photoelectrochemical solar cells, photocatalysis, and electrocatalysis.
Abstract: Graphene-based assemblies are gaining attention as a viable alternate to boost the efficiency of various catalytic and storage reactions in energy conversion applications. The use of reduced graphene oxide has already proved useful in collecting and transporting charge in photoelectrochemical solar cells, photocatalysis, and electrocatalysis. In many of these applications, the flat carbon serves as a scaffold to anchor metal and semiconductor nanoparticles and assists in promoting selectivity and efficiency of the catalytic process. Covalent and noncovalent interaction with organic molecules is another area that is expected to provide new frontiers in graphene research. Recent advances in manipulating graphene-based two-dimensional carbon architecture for energy conversion are described.
602 citations
TL;DR: Interestingly, the films which exhibited the fastest electron transfer rates were not the same as those which showed the highest photocurrent, suggesting that, in addition to electron transfer at the quantum dot-metal oxide interface, other electron transfer reactions play key roles in the determination of overall device efficiency.
Abstract: Quantum dot-metal oxide junctions are an integral part of next-generation solar cells, light emitting diodes, and nanostructured electronic arrays. Here we present a comprehensive examination of electron transfer at these junctions, using a series of CdSe quantum dot donors (sizes 2.8, 3.3, 4.0, and 4.2 nm in diameter) and metal oxide nanoparticle acceptors (SnO2, TiO2, and ZnO). Apparent electron transfer rate constants showed strong dependence on change in system free energy, exhibiting a sharp rise at small driving forces followed by a modest rise further away from the characteristic reorganization energy. The observed trend mimics the predicted behavior of electron transfer from a single quantum state to a continuum of electron accepting states, such as those present in the conduction band of a metal oxide nanoparticle. In contrast with dye-sensitized metal oxide electron transfer studies, our systems did not exhibit unthermalized hot-electron injection due to relatively large ratios of electron cooling rate to electron transfer rate. To investigate the implications of these findings in photovoltaic cells, quantum dot-metal oxide working electrodes were constructed in an identical fashion to the films used for the electron transfer portion of the study. Interestingly, the films which exhibited the fastest electron transfer rates (SnO2) were not the same as those which showed the highest photocurrent (TiO2). These findings suggest that, in addition to electron transfer at the quantum dot-metal oxide interface, other electron transfer reactions play key roles in the determination of overall device efficiency.
601 citations
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TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.
Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …
33,785 citations
TL;DR: Two organolead halide perovskite nanocrystals were found to efficiently sensitize TiO(2) for visible-light conversion in photoelectrochemical cells, which exhibit strong band-gap absorptions as semiconductors.
Abstract: Two organolead halide perovskite nanocrystals, CH3NH3PbBr3 and CH3NH3PbI3, were found to efficiently sensitize TiO2 for visible-light conversion in photoelectrochemical cells. When self-assembled on mesoporous TiO2 films, the nanocrystalline perovskites exhibit strong band-gap absorptions as semiconductors. The CH3NH3PbI3-based photocell with spectral sensitivity of up to 800 nm yielded a solar energy conversion efficiency of 3.8%. The CH3NH3PbBr3-based cell showed a high photovoltage of 0.96 V with an external quantum conversion efficiency of 65%.
16,634 citations
TL;DR: This work reviews the historical development of Transition metal dichalcogenides, methods for preparing atomically thin layers, their electronic and optical properties, and prospects for future advances in electronics and optoelectronics.
Abstract: Single-layer metal dichalcogenides are two-dimensional semiconductors that present strong potential for electronic and sensing applications complementary to that of graphene.
13,348 citations
TL;DR: A review of gold nanoparticles can be found in this article, where the most stable metal nanoparticles, called gold colloids (AuNPs), have been used for catalysis and biology applications.
Abstract: Although gold is the subject of one of the most ancient themes of investigation in science, its renaissance now leads to an exponentially increasing number of publications, especially in the context of emerging nanoscience and nanotechnology with nanoparticles and self-assembled monolayers (SAMs). We will limit the present review to gold nanoparticles (AuNPs), also called gold colloids. AuNPs are the most stable metal nanoparticles, and they present fascinating aspects such as their assembly of multiple types involving materials science, the behavior of the individual particles, size-related electronic, magnetic and optical properties (quantum size effect), and their applications to catalysis and biology. Their promises are in these fields as well as in the bottom-up approach of nanotechnology, and they will be key materials and building block in the 21st century. Whereas the extraction of gold started in the 5th millennium B.C. near Varna (Bulgaria) and reached 10 tons per year in Egypt around 1200-1300 B.C. when the marvelous statue of Touthankamon was constructed, it is probable that “soluble” gold appeared around the 5th or 4th century B.C. in Egypt and China. In antiquity, materials were used in an ecological sense for both aesthetic and curative purposes. Colloidal gold was used to make ruby glass 293 Chem. Rev. 2004, 104, 293−346
11,752 citations
TL;DR: Film and powders of TiO2-x Nx have revealed an improvement over titanium dioxide (TiO2) under visible light in optical absorption and photocatalytic activity such as photodegradations of methylene blue and gaseous acetaldehyde and hydrophilicity of the film surface.
Abstract: To use solar irradiation or interior lighting efficiently, we sought a photocatalyst with high reactivity under visible light. Films and powders of TiO 2- x N x have revealed an improvement over titanium dioxide (TiO 2 ) under visible light (wavelength 2 has proven to be indispensable for band-gap narrowing and photocatalytic activity, as assessed by first-principles calculations and x-ray photoemission spectroscopy.
11,402 citations