Low-cost and effective cocatalysts nickel oxides were deposited on CdS via a simple in situ photodeposition under different solution. It was found that the environment of photodeposition played a critical role in photocatalytic H-2 evolution activities. CdS loaded nickel oxide in alkaline solution showed the highest activity of photocatalytic hydrogen production, reaching to 590.8 mu mol h(-1) when the mole ratio of Ni2+ and CdS was 0.01, which was 117 times higher than that of pure CdS. The high photocatalytic hydrogen production activity might be attributed to the following reasons: (1) NiO could disperse on CdS tightly; (2) the OH- in the alkaline solution could be benefit for the transfer of holes. Thus, the holes and electrons could be separated efficiently. (C) 2014 Elsevier B.V. All rights reserved.