Highly efficient hydrogen evolution catalysis by MoS2-MoN/carbonitride composites derived from tetrathiomolybdate/polymer hybrids

Sustainable hydrogen production from water splitting has attracted much attention due to the promising alternatives to carbon-based fuels without the emission of carbon dioxide. However, Pt-group materials are both expensive and low abundant, which fuels the desire to gain cost-effective and alternative electrocatalysts for hydrogen production. Molybdenum disulfide (MoS2) has emerged as a promising material for hydrogen production by hydrogen evolution reaction (HER), but its performance is currently limited by poor electron transport or low active sites. Herein, a new synthetic route was developed to fabricate nitrogen-incorporated MoS2/carbonitride nanomaterials by a facile polymerization reaction and a subsquent thermal annealing process. The in-situ confinement of MoS2 nanoparticles into carbonitride framework were achieved through the reaction between ammonium tetrathiomolybdate and protons released from the homogeneous polymerization of 2,6-diaminopyridine. The nitrogen incorporation after annealing with NH3 can effectivly regulate the electronic structure and further improve the intrinsic conductivity. The resulted MoN-MoS2/carbonitride composite exhibits remarkable HER activity with onset overpotential as low as 30 mV, accompanied by extremely large cathodic current density (52.4 mA/cm(2) at eta=200 mV), a small Tafel slope (52 mV decade(-1)) and excellent stability (10000 cycles) due to synergistic effects and confinement effects. The composite via polymerization reaction in situ and a subsquent thermal annealing process is a promising strategy towards promising alternative catalyst for platinum-based HER electrocatalysts. (C) 2015 Elsevier Ltd. All rights reserved.