Promoted Electrochemical Hydrogen Evolution Kinetics by Anchoring Pt Nanoparticles on a Conductive Ti₄O₇ Support

Ensuring efficient noble metal utilization while maintaining rapid electron transport and long-term durability remains a central challenge in the acidic hydrogen evolution reaction (HER). Herein, we report a platinum catalyst supported on Magneli phase Ti₄O₇, a conductive oxide obtained via the hydrogen reduction of TiO₂(B), in which the support plays an active electronic role rather than serving as an inert scaffold. Electrochemical and spectroscopic analyses reveal that the mixed Ti³⁺/Ti⁴⁺ valence states and high electrical conductivity of Ti₄O₇ enable strong electronic coupling with Pt, leading to reduced charge-transfer resistance and more favorable hydrogen adsorption kinetics. As a result, the optimized 3 wt % Pt/Ti₄O₇ catalyst achieves an overpotential of 13 mV at 10 mA cm^-2 with sustained activity over 100 h in 0.5 M H₂SO₄. These findings demonstrate that conductive oxide supports can actively regulate interfacial electron transfer and reaction kinetics, offering a viable strategy for low noble metal loading and high-performance HER catalysts.