Appropriate dispersion of cocatalyst on semiconductor for improving photocatalytic H-2 production efficiency is a challenging work in semiconductor photocatalysis. Herein, we constructed the noble-metal-free CoSx modified tubular sulfur doped carbon nitride (SCN) photocatalysts by chemical precipitation process. The amorphous CoSx well dispersed on SCN served as H-2 production sites, which reduced the overpotential and inhibited the recombination of photogenerated carriers by interfacial charge transfer. Maximized H-2 production rate of 573.06 mu mol g(-1) h(-1) under visible light irradiation was obtained by optimizing the CoSx loading proportion to 2.4%, which was higher than that of 0.75 wt% Pt/SCN. In addition, a possible mechanism for improved H-2 production activity was proposed based on the experiments and discussion. This work provides a new strategy to design rational structure of non-noble metal cocatalyst modified photocatalyst to further improve H-2 production performance. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.