Hydrothermally Synthesis and Properties of Mesoporous Molybdenum Disulfide (MoS₂) - Reduced Graphene Oxide Composites for Hydrogen production

Graphene and related two-dimensional layered materials are attracting attention due to inherent advantages as potential game changers at the grand challenges of energy-water nexus. These technologies require delicate control over geometric and electronic structures affecting physical-electrochemical properties. In this study, we prepared three-dimensional aerogels consisting of varying graphene oxide-MoS₂ (molybdenum disulfide) ratio under hydrothermal conditions (P < 20 bar, T <200 ^oC) and synergy of PVP and components. We systematically characterized designed heterostructure interfaces, understand interaction through optical absorption and Raman spectroscopy (RS), to correlate between number defect density (via RS) and electrocatalytic activity. We demonstrate that controlled defects density (desulfurization), edges plane sites, hierarchical porosity and topological interconnectedness (monolithic aerogels) invoked can finely tune morphological structure and enhance activity towards electrocatalytic hydrogen production with a low Tafel slope ~77 mV·dec⁻¹. Additionally, Raman spectral bands are analyzed and the pore size distribution and mesoporosity are determined from electron microscopy and tomography.