Preparation of Ti@NiB electrode via electroless plating toward high-efficient alkaline simulated seawater splitting

Synthesis of Urchin-like Ni@NP@NCP Composites with Three Solvothermal Systems for Highly Efficient Overall Seawater Splitting

In this work, an urchin-like Ni@Ni₂P@NiCoP (Ni@NP@NCP) composite was prepared on nickel foam by a simple hydrothermal treatment process. Using the prepared NiO nanosheets as templates, the NiCo precursor was prepared in the presence of three solvothermal systems of water/dimethylformamide (DMF)/dimethyl sulfoxide (DMSO) by the hydrothermal process. After mixing and calcining with sodium hypophosphite under a nitrogen atmosphere at a high temperature for phosphating, an urchin-like Ni@NP@NCP(F/SO/H) nanostructured catalyst was obtained with superior hydrogen evolution and oxygen evolution performance. To further explore their efficiency in seawater splitting. Ni@NP@NCP(F/SO/H) composites were used as the cathode and anode of an electrolytic cell, which delivered 1.822 V potential at 300 mA cm^-2 in simulated seawater (1 M KOH and 0.5 M NaCl). This may provide an effective way of developing clean energy.

Quantum dot-doped CeOx-NiB with modulated electron density as a highly efficient bifunctional electrocatalyst for water splitting

Development of economical, efficient and durable non-noble metal electrocatalysts for the hydrogen/oxygen evolution reaction (HER/OER) holds great promise, but still faces great challenges. Herein, a strategy of doping metal borides with rare earth metal oxides and introducing silicon carbide (SiC) quantum dots has been explored to develop efficient bifunctional electrocatalysts. A novel electrocatalyst consists of SiC quantum dot-decorated CeO_x-NiB supported on nickel foam via a one-step mild electroless plating reaction (denoted as CeO_x-NiB/SiC@NF). Notably, the modulated electron density of the CeO_x-NiB/SiC@NF electrode significantly boosts the electrochemically active surface area and electron transfer, and optimizes the hydrogen/water absorption free energy, which delivers current densities of 50 mA cm^-2 and 10 mA cm^-2 at overpotentials of only 131 mV and 234 mV for the HER and the OER, respectively. The target electrode requires only 1.43 V to provide 10 mA cm^-2 for overall water splitting in 1.0 M KOH. Moreover, the electrode also exhibits good stability and durability at the industrial-grade current density (0.5-1 A cm^-2). This work provides a new idea for the development of efficient and durable non-precious metal catalysts.

Recent Advances in Seawater Electrolysis

Hydrogen energy, as a clean and renewable energy, has attracted much attention in recent years. Water electrolysis via the hydrogen evolution reaction at the cathode coupled with the oxygen evolution reaction at the anode is a promising method to produce hydrogen. Given the shortage of freshwater resources on the planet, the direct use of seawater as an electrolyte for hydrogen production has become a hot research topic. Direct use of seawater as the electrolyte for water electrolysis can reduce the cost of hydrogen production due to the great abundance and wide availability. In recent years, various high-efficiency electrocatalysts have made great progress in seawater splitting and have shown great potential. This review introduces the mechanisms and challenges of seawater splitting and summarizes the recent progress of various electrocatalysts used for hydrogen and oxygen evolution reaction in seawater electrolysis in recent years. Finally, the challenges and future opportunities of seawater electrolysis for hydrogen and oxygen production are presented.