This report describes the synthesis of a layered molybdenum disulfide (MoS2)–tungsten disulfide (WS2) heterostructure onto fluorine doped tin oxide covered glass substrates using a combination of chemical bath deposition and RF sputtering techniques. FESEM images revealed that the MoS2–WS2 heterostructure surface consisted of a cauliflower structured array of grains with spherical structures. The vertically aligned atomic layers were explored by transmission electron microscopy images for MoS2–WS2 heterostructure. Hydrogen evolution reaction (HER) kinetics show overpotentials of 151 and 175 mV @ 10 mA/cm2 with Tafel slope values of 90 and 117 mV/decade for pristine MoS2 and WS2 electrocatalysts, respectively. Improved electrocatalytic activity for HER was established with overpotential 129 mV @ 10 mA/cm2 and Tafel slope 72 mV/decade for the MoS2–WS2 heterostructure. The MoS2–WS2 heterostructure electrocatalyst showed robust continuous HER performance over 20 h in an acidic solution. This improved electrochemical performance emerges from the elevation of electron–hole separation at the layer interfaces and sharing of active edge sites through the interface. This study provides the basis to develop new applications for transition-metal dichalcogenides heterostructures in future energy conversion systems.

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Hydrogen (H2) is a clean and renewable energy source with a vital role to reduce global dependence on fossil fuels. H2 evolution through electrochemical reduction of water is an essential eco-friendly strategy, and cost-effective electrocatalysts are critical for large scale manufacturing. This paper proposes metal (Cu, Fe, and Mn)-doped nanostripes-structured molybdenum selenide (MoSe2) electrocatalysts for the H2 evolution reaction (HER). For the first time, a solution deposition technique was successfully employed to architect the basal plane edges in nanostripes-structured MoSe2 through metal doping for enhanced HER. Cu-doped MoSe2 exhibited ∼86 mV overpotential with a small Tafel slope (∼44 mV/dec) which is greater among the available MoSe2-based catalysts. An outstanding robustness was observed in an acidic medium for constant HER over 20 h. First-principles density function theory (DFT) approximations showed that charge transfer between the doped metal and MoSe2 increased the density of states near the Fermi level, enriching HER. DFT calculations also revealed that Cu-doped MoSe2 have low Gibbs free energy (0.13 eV) for H2 adsorption. Theoretical approximations, good stability, and nanostripe structures confirmed metal-doped MoSe2 as superior electrocatalysts for large scale H2 production.