Highly Dispersed and Small-Sized Nickel(II) Hydroxide Co-Catalyst Prepared by Photodeposition for Hydrogen Production.

Photodeposition has been widely used as a mild and efficient synthetic method to deposit co-catalysts. It is also worth studying how to synthesize non-noble metal photocatalysts with uniform dispersion. Different synthetic conditions in photodeposition have a certain influence on particle size distribution and photocatalytic activity. Therefore, we designed experiments to prepare the inexpensive composite photocatalyst Ni(OH)2 /g-C3 N4 by photodeposition. The Ni(OH)2 co-catalysts disperse uniformly with particle sizes of about 10 nm. The photocatalytic hydrogen production rate of Ni(OH)2 /g-C3 N4 reached about 19 mmol g-1  h-1 , with the Ni(OH)2 deposition amount about 1.57 %. During 16 h stability testing, the rate of hydrogen production did not decrease significantly. The composite catalyst also revealed a good hydrogen production performance under sunlight. The Ni(OH)2 co-catalyst enhanced the separation ability of photogenerated carriers, which was proved by surface photovoltage and fluorescence analysis.