Designing sulfide catalysts for H2S dissociation to H2 based on reaction descriptors and microkinetics

Abstract

Molybdenum disulfide (MoS2) is a promising catalyst for the challenging transformation of hydrogen sulfide (H2S) into sulfur and hydrogen (H2). However, a detailed understanding of its structure-function correlation still needs to be provided. We used density functional theory calculations to extract relevant reaction indexes (binding energies and free energy barriers) over different MoS2 surfaces. We used these indexes as inspiration in developing new catalysts and a microkinetic model to compare the results, extracting insights into the reaction mechanisms and surface coverages. The turnover frequencies obtained experimentally and through microkinetic modeling are analogous, validating our approach. The findings pave the way for developing more efficient H2S decomposition catalysts and establish a descriptor-based design for other metal sulfide catalysts.