Robust Pt/TiO2/Ni(OH)2 nanosheet arrays enable outstanding performance for high current density alkaline water electrolysis

Herein, we developed a novel and simple strategy to construct Pt-decorated TiO 2 /β-Ni(OH) 2 nanosheet arrays that steadily deliver large current densities in alkaline electrolyte. It is of great interest to find that the versatile role of few-layered Ti 3 C 2 endows the unique growth mechanism of Pt/TiO 2 /β-Ni(OH) 2 . It is worth noting that the interconnected array electrode exhibits noticeable hydrogen evolution reaction (HER) performance, achieving ultralow overpotentials of 107, 145 and 184 mV at high current densities of 500, 1000 and 1500 mA cm −2 , respectively, which outperforms most reported HER electrocatalysts. It requires only 1.95 V to drive 1000 mA cm −2 towards full water electrolysis along with considerable stability. It is demonstrated for the first time that the synergistic effect of Pt and TiO 2 /Ni(OH) 2 the enhanced HER performance. This work reports a robust nanoarray support for Pt electrocatalyst to break through its intrinsic barrier in alkaline HER and under large current density. A novel and simple strategy was proposed to construct robust Pt-decorated TiO 2 /β-Ni(OH) 2 nanosheet arrays that steadily deliver industrial current densities at ultralow overpotentials in alkaline electrolyte. The unexpected HER activity originates from the synergy between Pt and TiO 2 /Ni(OH) 2 along with the interconnected array architecture. • Pt/TiO 2 /Ni(OH) 2 /NF possesses ultralow HER overpotential at high current density. • Pt/TiO 2 /Ni(OH) 2 /NF couple requires small cell voltage for overall water splitting. • 2D MXene endows the unique growth mechanism of Pt/TiO 2 /β-Ni(OH) 2 nanosheet. • The synergy between Pt and TiO 2 /Ni(OH) 2 contributes to the enhanced HER activity. • The interconnected array architecture overcomes the mass transfer resistance.