@article { ISI:000289763700026, title = {Low temperature pH dependent synthesis of flower-like ZnO nanostructures with enhanced photocatalytic activity}, journal = {Materials Research Bulletin}, volume = {46}, number = {5}, year = {2011}, month = {MAY}, pages = {771-778}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

In the present study we have synthesized flower-like ZnO nanostructures comprising of nanobelts of 20 nm width by template and surfactant free low-temperature (4 degrees C) aqueous solution route. The ZnO nanostructures exhibit flower-like morphology, having crystalline hexagonal wurtzite structure with (001) orientation. The flowers with size between 600 and 700 nm consist of ZnO units having crystallite size of similar to 40 nm. Chemical and structural characterization reveals a significant role of precursor: ligand molar ratio, pH, and temperature in the formation of single-step flower-like ZnO at low temperature. Plausible growth mechanism for the formation of flower-like structure has been discussed in detail. Photoluminescence studies confirm formation of ZnO with the defects in crystal structure. The flower-like ZnO nanostructures exhibit enhanced photochemical degradation of methylene blue (MB) with the increased concentration of ligand, indicating attribution of structural features in the photocatalytic properties. (C) 2010 Elsevier Ltd. All rights reserved.

}, keywords = {Catalytic properties, Defects, Nanostructures, Optical properties, Semiconductor}, issn = {0025-5408}, doi = {10.1016/j.materresbull.2010.11.007}, author = {Vaishampayan, Mukta V. and Mulla, Imtiaz S. and Joshi, Satyawati S.} } @article { ISI:000349088000020, title = {Oxidation catalysis by large trisoctahedral gold nanoparticles: Mind the step!}, journal = {Catalysis Today}, volume = {244}, year = {2015}, month = {APR}, pages = {177-183}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

To understand the origin of catalysis by gold and to probe the role of defects and interfaces, benchmark reactions namely CO oxidation and benzyl alcohol oxidation were carried out on supported trisoctahedral gold nanoparticles and on the inverse catalyst system. The sizes of these particles which are between 45 nm and 110 nm, are well beyond the quantum size regime and well above the optimum size range where gold is considered to be catalytically active. The periodic steps sites in contact with oxide support interface were able to promote the reaction. (C) 2014 Elsevier B.V. All rights reserved.

}, keywords = {CO oxidation, Defects, Gold catalysis, Inverse catalysta, Steps and kinks}, issn = {0920-5861}, doi = {10.1016/j.cattod.2014.02.049}, author = {Sreedhala, S. and Sudheeshkumar, V. and Vinod, C. P.} } @article {44194, title = {Marginally hydrogenated triphasic titania nanotubes for effective visible-light photocatalytic hydrogen generation}, journal = {Energy Technology}, volume = {6}, year = {2018}, month = {FEB}, pages = {280-288}, type = {Article}, abstract = {

We report the first demonstration of hydrogen-annealed triphase TiO nanotubes (anatase-rutile-brookite) (T-ARB) as a visible-light-active photocatalyst for water splitting with high quantum efficiency. As-synthesized T-ARB was annealed under hydrogen atmosphere at 250 and 4508 degrees C for 2 h. We found that the tubular structures were retained in the hydrogenated TiO2 samples. It was observed that the concentrations of Ti3+ and the oxygen vacancies and their distribution significantly increased with respect to the hydrogen annealing temperature. Such changes in defects were found to be critical in enhancing the photocatalytic activity of the hydrogen-annealed triphase TiO2 nanotubes. The triphase TiO2 nanotubes hydrogen annealed at 450 degrees C were 16 times more efficient than pristine TiO2. Such an increase in the photocatalytic activity was explained by a triphase band diagram with defect states below the conduction band of each phase, which facilitated visible-light activity and easy transfer of charge carriers from one phase to another. Our study showed that the well-designed multiphase construction with oxygen vacancies enhanced the photocatalytic activity tremendously owing to the presence of a higher number of phase junctions.

}, keywords = {charge transfer, Defects, Hydrogenation, titania, water splitting}, issn = {2194-4288}, doi = {10.1002/ente.201700406}, author = {Preethi, Laguduva K. and Mathews, Tom and Walczak, Lukasz and Gopinath, Chinnakonda S.} } @article {49221, title = {Interface-centric strategies in kesterite solar cells: addressing challenges, solutions, and future directions for efficient solar-harvesting technologies}, journal = {SMALL}, volume = {20}, year = {2024}, month = {DEC}, type = {Review}, keywords = {band engineering, Defects, interface loss mechanism, kesterites, recombination control, solar energy}, issn = {1613-6810}, doi = {10.1002/smll.202402048}, author = {Jagadish, Kusuma and Rahane, Ganesh K. and Kumar, Boddeda Sai and Borkar, Durgesh R. and Chordiya, Kalyani and Kavanagh, Sean R. and Roy, Anurag and Debnath, Tushar and Kolekar, Sadhu and Kahaly, Mousumi Upadhyay and Mali, Sawanta S. and Pal, Shovon and Gasparini, Nicola and Dubal, Deepak P. and Rondiya, Sachin R.} }