DEVELOPMENT OF TWO-DIMENSIONAL NANOSTRUCTURED TERNARY METAL SULFIDES FOR HYDROGEN PRODUCTION

Abstract

In this dissertation, ternary sulfides consisted of earth abundant elements are engaged through scalable processes to create two-dimensional nanostructured photocatalyst and electrocatalyst for hydrogen evolution reaction. Firstly, metal sulfide cocatalysts are loaded onto ternary sulfide photocatalyst via photo-assisted deposition method. The effects of electrocatalytic cocatalyst in providing optimal H2 evolution surface active sites for photocatalysis are investigated. Secondly, unique hierarchical nanostructure ternary sulfide electrode is created using hydroxide template. The synergy of hierarchical nanostructure in promoting gas evolution dynamics towards electrocatalytic water splitting are studied. Thirdly, in addition to ternary sulfide photocatalyst, oxide layer and p-n heterojunction are successively incorporated through annealing and photo-assisted deposition. The enhanced kinetics of photocatalytic activity by both layers are presented. Lastly, ternary sulfide photocatalyst, p-n heterojunction, oxide layer and electrocatalytic cocatalyst are all integrated into H2 evolution photocathode via scalable techniques to efficiently utilize photo-induced charge carriers for solar hydrogen evolution in photoelectrochemical cell.