In-situ transformational mycelium-like metal phosphides-encapsulated carbon nanotubes coating on the stainless steel mesh as robust self-supporting electrocatalyst for water splitting

Abstract

Herein, In-situ conversional mycelium-like metal phosphides-encapsulated N, P co-doped carbon nanotubes (CNTs) coating on the stainless steel mesh (PSD-SM) as self-supporting electrocatalyst was fabricated via solid-diffusion (SD) and phosphorization process, which was the first time to fabricated the “chainmail for catalysts” use stainless steel mesh worked as self-reaction template and electrode-base materilas. The in-situ transformational mycelium-like CNTs array structure greatly enhanced the specific surface area of steel mesh and the graphitized carbon layer coating with high capacitance increases the electrochemical active sites. And the subsequent phosphorization treatment further improved the intrinsic catalytic activity of the material. PSD-SM exhibits the low overpotential of 231 mV at 10 mA·cm−2 with a Tafel slope of 88 mV·dec−1 for OER and 172 mV at 10 mA·cm−2 with a Tafel slope of 125 mV·dec−1 for HER. Further more, there are only 1.77 V deliver potential for water electrolysis of PSD-SM at 10 mA·cm−2 and the kinetic mechanism of as-fabricated samples for HER and OER was analyzed by Tafel slope and other measurement. This report provides an promising method to prepare efficient and robust electrocatalytic materials based on steel mesh for practical application.