Titanium nitride supported ternary metal phosphides for hydrogen evolution

Increasing the number of active sites is of utmost importance for developing highly efficient hydrogen evolution reaction (HER) electrocatalysts. Herein, we prepared titanium nitride (TiN) nanowire supported ternary metal phosphide (FeCoNiPx) catalysts (TFCNP) for hydrogen evolution. The high conductivity and high surface area of TiN enhanced the charge transfer efficiency, significantly increased the number of exposed active sites, and prevented the migration and aggregation of catalysts. As a result, the TFCNP catalyst shows excellent performance for the HER, with an overpotential of 72 mV and 133 mV at 10 mA cm-2 under alkaline and acidic conditions, respectively. In addition, an anion exchange membrane water electrolyzer was constructed with the TFCNP HER catalyst and NiFe LDH OER catalyst, achieving a current density of 50 mA cm-2 at 1.57 V and stability over 150 h under industrial operating conditions. A heterostructure of FeCoNiPx-decorated TiN nanowires was fabricated towards the HER both in alkaline and acidic electrolytes. Furthermore, an alkaline electrolyzer (NiFe LDH//AEM//TFCNP) could remain stable for more than 150 h at 300 mA cm-2.