Water electrolysis is an advanced energy conversion technology to produce hydrogen as a clean and sustainable chemical fuel, which potentially stores the abundant but intermittent renewable energy sources scalably. Since the overall water splitting is an uphill reaction in low efficiency, innovative breakthroughs are desirable to greatly improve the efficiency by rationally designing non-precious metal-based robust bifunctional catalysts for promoting both the cathodic hydrogen evolution and anodic oxygen evolution reactions. We report a hybrid catalyst constructed by iron and dinickel phosphides on nickel foams that drives both the hydrogen and oxygen evolution reactions well in base, and thus substantially expedites overall water splitting at 10 mA cm−2 with 1.42 V, which outperforms the integrated iridium (IV) oxide and platinum couple (1.57 V), and are among the best activities currently. Especially, it delivers 500 mA cm−2 at 1.72 V without decay even after the durability test for 40 h, providing great potential for large-scale applications.

A robust oxygen-evolving electrocatalyst was developed using a room-temperature strategy for water splitting at high current densities with low voltages.

With the massive consumption of fossil fuels and its detrimental impact on the environment, methods of generating clean power are urgent. Hydrogen is an ideal carrier for renewable energy; however, hydrogen generation is inefficient because of the lack of robust catalysts that are substantially cheaper than platinum. Therefore, robust and durable earth-abundant and cost-effective catalysts are desirable for hydrogen generation from water splitting via hydrogen evolution reaction. Here we report an active and durable earth-abundant transition metal dichalcogenide-based hybrid catalyst that exhibits high hydrogen evolution activity approaching the state-of-the-art platinum catalysts, and superior to those of most transition metal dichalcogenides (molybdenum sulfide, cobalt diselenide and so on). Our material is fabricated by growing ternary molybdenum sulfoselenide particles on self-standing porous nickel diselenide foam. This advance provides a different pathway to design cheap, efficient and sizable hydrogen-evolving electrode by simultaneously tuning the number of catalytic edge sites, porosity, heteroatom doping and electrical conductivity.

Exceptional Pt-like electrocatalytic activity was achieved in a sandwich-like catalyst of CoP/Ni5P4/CoP microsheet arrays for pH-universal hydrogen evolution through simply wrapping Ni5P4 nanosheet arrays in CoP nanoparticles.

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Commercial hydrogen production by electrocatalytic water splitting will benefit from the realization of more efficient and less expensive catalysts compared with noble metal catalysts, especially for the oxygen evolution reaction, which requires a current density of 500 mA/cm at an overpotential below 300 mV with long-term stability. Here we report a robust oxygen-evolving electrocatalyst consisting of ferrous metaphosphate on self-supported conductive nickel foam that is commercially available in large scale. We find that this catalyst, which may be associated with the in situ generated nickel-iron oxide/hydroxide and iron oxyhydroxide catalysts at the surface, yields current densities of 10 mA/cm at an overpotential of 177 mV, 500 mA/cm at only 265 mV, and 1,705 mA/cm at 300 mV, with high durability in alkaline electrolyte of 1 M KOH even after 10,000 cycles, representing activity enhancement by a factor of 49 in boosting water oxidation at 300 mV relative to the state-of-the-art IrO catalyst.

The photoreduction of CO2 to hydrocarbon products has attracted much attention because it provides an avenue to directly synthesize value‐added carbon‐based fuels and feedstocks using solar energy. Among various photocatalysts, graphitic carbon nitride (g‐C3N4) has emerged as an attractive metal‐free visible‐light photocatalyst due to its advantages of earth‐abundance, nontoxicity, and stability. Unfortunately, its photocatalytic efficiency is seriously limited by charge carriers′ ready recombination and their low reaction dynamics. Modifying the local electronic structure of g‐C3N4 is predicted to be an efficient way to improve the charge transfer and reaction efficiency. Here, boron (B) is doped into the large cavity between adjacent tri‐s‐triazine units via coordination with two‐coordinated N atoms. Theoretical calculations prove that the new electron excitation from N (2px, 2py) to B (2px, 2py) with the same orbital direction in B‐doped g‐C3N4 is much easier than N (2px, 2py) to C 2pz in pure g‐C3N4, and improves the charge transfer and localization, and thus the reaction dynamics. Moreover, B atoms doping changes the adsorption of CO (intermediate), and can act as active sites for CH4 production. As a result, the optimal sample of 1%B/g‐C3N4 exhibits better selectivity for CH4 with ≈32 times higher yield than that of pure g‐C3N4.

Exploring efficient and durable catalysts from earth-abundant and cost-effective materials is highly desirable for the sluggish anodic oxygen evolution reaction (OER), which plays a key role in water splitting, fuel cells, and rechargeable metal−air batteries. First-row transition-metal (Ni, Co, and Fe)-based compounds are promising candidates as OER catalysts to substitute the benchmark of noble-metalbased catalysts, such as IrO 2 and RuO 2 . Although Fe is the cheapest and one of the most abundant transition-metal elements, there are seldom papers reported on Fe-only compounds with outstanding catalytic OER activities. Here we propose an interesting strategy by growing iron nitride (Fe 3 N/Fe 4 N) based nanoporous film on three-dimensional (3D) highly conductive graphene/Ni foam, which is demonstrated to be a robust and durable self-supported 3D electrode for the OER featuring a very low overpotential of 238 mV to achieve a current density of 10 mA/cm 2 , a small Tafel slope of 44.5 mV/dec, good stability, and 96.7% Faradaic yield. The high OER efficiency is by far one of the best for single-metal (Fe, Co, and Ni)-based catalysts, and even better than that of the benchmark IrO 2 , which is attributed to the fast electron transfer, high surface area, and abundant active sites of the catalyst. This development introduces another member to the family of cost-effective and efficient OER catalysts.