Tuning the reactivity of Ni/MoS2 membrane for efficient methane pyrolysis and hydrogen production: A multi-scale study

Abstract

This study investigates the performance of a Ni-coated MoS2 membrane for catalysis and separation in the methane pyrolysis process. Bifunctional membranes provide a low-energy and low-emission hydrogen generation and purification production process. To elucidate the reaction mechanism of the prepared membrane, a combined experimental and computational approach was employed using ReaxFF molecular dynamics simulations. The results demonstrate excellent catalytic and separation performance of the membrane, which was achieved through the increased specific surface area and reduced pore size of the MoS2 flower cluster. The Ni coating of MoS2 was found to attract methane, and transfer electrons to destabilize the CH bond, thus enhancing methane deep crack. In addition, the prepared membrane successfully blocked methane through Mo-edge defects, while promoting methane pyrolysis and driving H proton transportation for the H2 formation. The permeation test verified the excellent CH4/H2 separation performance of the ZSM-5 membrane coated with Ni and MoS2. This work provides theoretical and experimental guidance for the development of bifunctional membranes for methane pyrolysis to hydrogen generation, which has potential to reduce energy cost and greenhouse gas emissions.