Enhanced interfacial stability of Pt/TiO2/Ti via Pt-O bonding for efficient acidic electrolyzer

The development of efficient and stable integrated electrodes is crucial for the advancement of electrolyzer. Herein, the ultra-low platinum (12.7 μgPt cm−2) anchored TiO2 nano-polyhedrons protective titanium fibers paper (Pt/TiO2/Ti) is synthesized as an integrated electrode for gas diffusion, current collector and catalytic hydrogen production. The Pt/TiO2/Ti electrode exhibits remarkable activity (23 mV at 10 mA cm−2) and durability (180 mA cm−2 for 25 h) for hydrogen evolution reaction in acidic electrolyte, which is attributed to the enhanced interface via Pt-O bond between Pt and TiO2. Specifically, the optimizing electronic structure of Pt anchoring on the TiO2 enhances hydrogen adsorption energy to improve the intrinsic activity of HER. In addition, the relatively negative adsorption energy (Eads) of Pt atom on TiO2 significantly contributes to the structural stability of the Pt/TiO2/Ti electrode. Moreover, the complete encapsulation of titanium fibers by TiO2 layer enhances the structural stability of Pt/TiO2/Ti by preventing hydrogenation-induced breakage of the titanium substrate. The constructed electrolyzer of (−) Pt/TiO2/Ti || IrO2/TiO2/Ti (+) presents efficient water splitting performance (1.464 V at 10 mA cm−2) and long-term durability (∼100 % retention for 30 h) in acidic electrolyte. This work highlights the importance of integrated electrodes and the feasibility of acidic electrolyzer.