The increasing demand for the energy and environmental concerns has induced global efforts to find and explore alternative energy sources for fossil fuels. As an ideal candidate, hydrogen produced from water splitting is an attractive next generation energy conversion device [1]. The noble metals are the most active in catalyzing the water electrolysis to produce pure hydrogen, but the high cost and elemental scarcity greatly hinder their widespread applications. The development of low-cost, efficient, and robust electro-catalysts (both oxygen evolution (OER) and hydrogen evolution (HER) catalysts) for water splitting is a crucial step toward the conversion and storage of sustainable energy resources such as solar energy. Not only the catalysts need to be composed of inexpensive elements, they are also desirable to be prepared at low energy cost [2,3,4].

   Here, we have investigated the inexpensive synthesis of electrochemically depositing the nickel iron sulfides on nickel foam for the highly efficient bi-functional water splitting to meet the current demand. Nickel iron sulfide on nickel foam (NiFeS/NF) showing the low over-potential about 230 mV for OER and 205 mV for the HER. This bi-functional catalyst also showing robust durability about 200 hours. The high performance and also the facile synthesis with strong coating on nickel foam make it commercial viable catalyst. The NiFeS/NF catalyst for large scale with highly efficient and durable bi-functional catalyst for water splitting outperform the noble metals such as IrO₂, RuO₂electrocatalysts. The details of direct synthesis, characterization of new transition metal sulfides on metallic substrates will be discussed in this presentation.

References:

[1] N. Jiang, L. Bogoev, M. Popova, S. Gul, J. Yanob, Y. Sun, J. Mater. Chem. A, 2014, 2,19407–19414.

[2] P. Ganesan, M. Prabu, J. Sanetuntikul, S. Shanmugam, ACS Catal., 2015, 5, 3625-3637.

[3] X. Long, G. Li, Z. Wang, H. Y. Zhu, T. Zhang, S. Xiao, W. Guo, S. Yang, J. Am. Chem. Soc.    

   2015, 137, 11900−11903.

[4] C. Tang, Z. Pu, Q. Liu, A. M. Asiri, X. Sun, Electrochimica Acta. 2015, 153, 508–514