Kolay, Ankita and Maity, Debanjan and Ghosal, Partha and M, Deepa
(2019)
Selenium Nanoparticles Decorated Silicon Nanowires with Enhanced Liquid Junction Photoelectrochemical Solar Cell Performance.
Journal of Physical Chemistry C.
pp. 1-14.
ISSN 1932-7447
(In Press)
Full text not available from this repository.
(
Request a copy)
Abstract
Selenium nanoparticles decorated silicon nanowires (Se NPs@Si NWs) electrode is applied as a photoanode in a liquid junction photoelectrochemical (PEC) solar cell for the first time. Upon illumination, the Se NPs anchored along the axial length of Si NWs allow fast hole extraction at the radial Se/Si junctions, due to the p-type conduction nature of Se NPs thus enhancing electron-hole separation, and simultaneously increase the population of photoexcited electrons in Si NWs through light scattering that amplifies the effective light absorption of Si NWs. These attributes of Se NPs result in a power conver-sion efficiency (PCE) of 7.03% for the Se NPs@Si NWs based liquid junction solar cell encompassing a Br-/Br2 electrolyte and a carbon fabric counter electrode. This PCE is greater by 43% than that of the analogous Si NWs based cell. Se NPs are photo-conducting due to facile hole-propagation that occurs particularly along the c-axis of trigonal Se NPs with a hexago-nal crystal structure, and size effects improve the optical path length, factors that lead to a significantly improved perfor-mance. Compared to Pt or Au NPs that have been explored previously in combination with Si NWs, where their roles are distinctively different, Se NPs here, are not only more cost effective, and easy to synthesize on a large-scale, but they enable an improvement in PCE of Si NWs, by relying on unique mechanisms. Optical-, structural-, PEC-, and impedance- studies furnish a deep understanding of the phenomena involved in yielding a superior performing liquid junction PEC solar cell based on the Se NPs@Si NWs photoanode.
Actions (login required)
 |
View Item |
Altmetric
Altmetric