Ultrathin molybdenum sulfide (MoSx) nanosheets were uniformly grown on multiwalled carbon nano tubes (MWCNTs) via a solvothermal process. These MoSx nanosheets possess high density of active sites, full of the basal MoSx edges and unsaturated S atoms, and their one-dimensional (1D) core-shell architecture facilitates electron transfer and charge transport, leading to a superior performance in H-2 evolution reaction (HER). These caterpillar-like MoSx@MWCNT hybrids show a high HER capability in 0.5 M H2SO4 solution with a low overpotential of 102 mV vs standard hydrogen electrode (SHE) and a small Tafel slope of 35 mV dec (1) at 10 mA cm (2). Their HER activity presents no significant decay during potential polarization at 150 mV vs SHE for over 5 h. (C) 2017 Elsevier Ltd. All rights reserved.