Catalyst-free hydrogen evolution of Si photocathode by thermovoltage-driven solar water splitting

JOURNAL OF POWER SOURCES

卷:279

Article

Shin, Sun-Mi¹  Jung, Jin-Young¹  Park, Min-Joon¹  Song, Jae-Won¹  Lee, Jung-Ho¹ 

[1] Hanyang Univ, Dept Mat & Chem Engn, Ansan 426791, South Korea

关键词: Photoelectrochemical cell;    Water splitting;    Hydrogen;    Thermovoltage;    Hybrid device;   

DOI  :  10.1016/j.jpowsour.2015.01.020

来源: Elsevier

【 摘 要 】

An externally biased overpotential is normally required for photoelectrochemically cleaving water molecules. Moreover, very few semiconductors exhibit the necessary performance for the efficient transfer of photon energy to the binding electrons of water molecules unless a suitable catalyst is present. Here, we present a catalyst-free photoelectrochemical (PEC) cell electrically coupled in series with a thermoelectric device, which is capable of utilizing the full solar spectrum by synergistically collecting photon and phonon energies. Thermodynamic overpotentials originally required for the PEC reaction were spontaneously offset by the thermovoltage, which adjusts the Fermi level of a counter-electrode. Using a catalyst-free Si photocathode of unbiased conditions, we achieved a photon-to-current efficiency of similar to 20% at an 56 degrees C temperature gradient by harnessing only solar energy. (C) 2015 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.orgilicenses/by-nc-nd/4.0/).

【 授权许可】

Free