A facile strategy of “laser-direct-writing” to develop self-supported Ni30B70–Ti catalysts for boosted and durable alkaline oxygen evolution

Abstract

Seawater splitting, which avoids limited freshwater resources, is a promising technology for producing renewable and sustainable hydrogen energy. In this work, a Ni₃₀B₇₀ catalyst supported on titanium foam (Ni₃₀B₇₀–Ti) was designed via two steps using ball milling and laser direct writing technology without adding binders. This process involved directly converting Ni–B powder into the NiB compound, firmly anchored on a titanium foam substrate. The overpotential of the Ni₃₀B₇₀–Ti catalyst was observed to be 370 mV at a current density of 50 mA cm⁻², 260 mV lower than that of the commercial nickel mesh. The Ni₃₀B₇₀–Ti catalyst exhibits excellent stability, as evidenced by its consistent performance at a high current density of 100 mA cm⁻² for an extended duration of 100 hours. This endurance can be attributed to the corrosion resistance of the titanium plate and the strong metallurgical bonding between the NiB catalysts and the titanium foam substrate. These findings pave the way for developing highly active, cost-effective, and durable catalytic electrodes that can be utilized for hydrogen production through seawater splitting.