Heterostructure engineering, combining dissimilar materials into a single substrate, allows tunning the optical, electrical and (photo)electrochemical properties of photoelectrodes for solar water-splitting.

A novel heterostructure has been developed by synergistically combining heterojunction and textured/facet engineering that can efficiently improve solar-to-hydrogen conversion.

Photoelectrochemical (PEC) water splitting is a promising route to store sunlight directly into chemical energy, such as green hydrogen. Monoclinic bismuth vanadate (BiVO4) has emerged as the most potential photoanode. However, it still suffers from low electron mobility and poor surface property. Furthermore, the PEC performance of BiVO4 alone is significantly limited by the high charge recombination in bulk and interface.

To address those limitation of BiVO4, the researchers led by Prof. Insun Cho developed a dual-textured heterostructure. The unique heterostructure consisting of a top layer of (001)-textured BiVO4 and a bottom layer of [001]-oriented Sb:SnO2(ATO) nanorods were successfully synthesized by employing a facile hydrothermal method.

Notably, dual-textured BiVO4/ATO heterostructure showed a considerable enhancement in charge collection performance, resulting in a photocurrent density about four times higher than that of the textured BiVO4 grown on the ATO nanoparticles film (randomly-oriented). Finally, we demonstrated a stable photocurrent density and Faradaic efficiency of over ~90% by coupling with the cobalt/iron oxyhydroxide ((Co,Fe)OOH) electrocatalyst.

 This research have been published in the international scientific journal 'Chemical Engineering Journal' (IF: 13.274, JCR%: 2.448)

[Reference] Jeong YJ et al., (2022) "Dual textured BiVO4/Sb:SnO2 heterostructure for enhanced photoelectrochemical water-splitting" Chemical Engineering Journal

[Main Author] Yoo Jae Jeong (Ajou University) & In Sun Cho (Ajou University)

* Contact : Professor In Sun Cho (insuncho@ajou.ac.kr)