Efficient Hydrogen Evolution Enabled by a Noble‐Metal‐Free NiTiCu Thin‐Film Metallic Glass Electrocatalyst

Abstract

Hydrogen is a promising green alternative to fossil fuels. However, the scarcity and high cost of platinum group metals pose a major economic challenge to the large‐scale production of hydrogen. To address this issue, we investigated a novel, noble‐metal‐free NiTiCu thin‐film metallic glass (TFMG). This film was successfully deposited onto a copper substrate via magnetron sputtering to serve as a cathode for the hydrogen evolution reaction (HER). The surface was characterized structurally and electrochemically for its ability to undergo HER in both acidic and alkaline environments. Ni8.46Ti5.52Cu86.01 film showed satisfactory performance in the alkaline environment compared with pure Cu and maintained its stability for 21 h, as confirmed by the chronopotentiometry test. Its ηonset and η10 were 193 and 360 mV versus RHE in alkaline media, respectively, while its Tafel slope was calculated to be 127 mV dec−1. The prepared coating noticeably increased the electrochemically active surface area of the Cu substrate from 24.25 to 227.5 cm2. Moreover, the satisfactory hydrophobicity of the surface, with a water contact angle of 104.1°, enhanced water‐splitting efficiency by facilitating bubble desorption from the surface. This study provides insight into the HER of NiTiCu‐based TFMGs and identifies the key factors that enhance their efficiency.