Study on the Electrocatalytic Performance of Porous Conductive Materials Based on an In Situ Growth of Bimetal Phosphides with Plasma

To find alternative solutions for the high cost of noble metals in the process of electrocatalytic hydrogen evolution, a hydrothermal method was used to in situ grow a precursor material with nanosheet (100 nm) and nanorod (100 nm) micromorphologies on the surface of a Ni foam (NF). Subsequently, phosphorylation was performed on the precursor surface by a plasma-enhanced chemical vapor deposition (PECVD) method to obtain a nickel-cobalt double metal phosphide with a needle-like nanoarray morphology. NiCoP-PECVD has a simple preparation method and a regular morphology, and it has excellent HER performance over a large pH range as evidenced from electrochemical tests. When the current density is 10 mA·cm -2 , the hydrogen evolution overpotentials in the acidic solution (0.5 M H 2 SO 4 ) and alkaline solution (1 M KOH) are 78 mV and 80 mV, respectively. Compared with Ni 2 P-PECVD and NiCoP-CVD, the above values are significant lower. The chronopotential (CP) test showed that the material has good HER stability over 12 h. The ECSA test results show that both the Co doping and the PECVD method can help to increase the number of active sites of the material and improve its electrocatalytic activity. The above results are favorable for designing and developing low-cost, high-efficiency transition metal phosphorus catalysts.