• Operating the stacked photoanode at the thickness of exciton diffusion length enhances the efficiency of photoelectrochemical water splitting

    • Fulltext

       

        Click here to view fulltext PDF


      Permanent link:
      https://www.ias.ac.in/article/fulltext/jcsc/133/0037

    • Keywords

       

      Photoelectrochemical water splitting; Photoelectrode thickness; Cadmium selenide; Stack; Exciton diffusion length; Optical absorption.

    • Abstract

       

      In photoelectrochemical water splitting, every impinging photon should not only be absorbed butalso be utilized towards reaction. While increasing photoelectrode thickness in photoelectrochemical reactorsfacilitates photon absorption, it has a debilitating effect on efficiency if the thickness required for completephoton absorption is much more than the exciton diffusion length, which is a property determined by thematerial and its processing. To address this issue, we demonstrate a general experimental methodology with astack of cadmium selenide photoanodes wherein the thickness of each photoelectrode is of the order ofexciton diffusion length and which improves overall photocurrent by about 50%.

    • Graphical Abstract

       

      Stacked-photo anodes for photoelectrochemical water splitting reaction with each anode having thickness ~ exciton diffusion length. The fraction of light transmitted from the previous anode oxidizes water into O2 and H+. The sum of the thickness of photoanodes is sufficient to absorb all incident light.

    • Author Affiliations

       

      ASHOK KUMAR UMMIREDDI1 RAJ GANESH S PALA2

      1. Department of Chemical Engineering, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208016, India
      2. Material Science Programme, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208016, India
    • Dates

       
  • Journal of Chemical Sciences | News

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

© 2021-2022 Indian Academy of Sciences, Bengaluru.