A challenging but very important task is the development of efficient and cost effective non-noble metal based bifunctional electrocatalysts with excellent kinetics for overall water splitting. Improving the catalyst’s electronic structure, optimizing intermediate adsorption, and enhancing charge transfer kinetics are crucial for enhancing reaction efficiency. In this study, we prepared three-dimensional structured V-doped CoP grown in situ on MXene by one-step hydrothermal and controlled phosphorylation (defined as V-CoP/MXene@NF). The V doping not only optimises the electronic conductivity, but also creates a strong synergistic effect between the MXene and V-CoP components, enriching the active sites of the catalysts. The V-CoP/MXene@NF electrocatalyst can achieve a current density of 10 mA·cm⁻² in 1.0 M KOH solution, with overpotentials of 78 and 223 mV for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), respectively. For overall water splitting, we used the catalyst as an anode and cathode assembly in an electrolytic cell, which could drive a current density of 10 mA·cm⁻² with an overpotential of only 1.56 V and excellent durability. This work provides new ideas for designing novel MXene-based non-noble metal bifunctional electrocatalysts.

Amorphous alloys are promising candidates for oxygen evolution reaction (OER) applications due to their unique structural features, including abundant active sites, tunable chemical composition and high structural flexibility. However, there is a main challenge in the improvement of stability due to the short-range order structure of amorphous alloys. In this work, we synthesized C-modified amorphous NiFe alloy (C-NiFe(BP)) via a novel one-step annealing method with the introduction of glucose at room temperature fermentation. The as-prepared C-NiFe(BP) achieves an ultra-low overpotential of 219.7 mV and a Tafel slope of 43.17 mV·dec⁻¹ at the current density of 10 mA·cm⁻², which surpass the reported amorphous NiFe (a-NiFe) based alloys in OER. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses reveal that carbon modification widens the spacing between catalyst layers, exposing more active sites and promoting charge transfer between elements, thereby improving OER performance. Moreover, the C-NiFe(BP) exhibits promising stability during durability test for 20 h and cyclic voltammetry test for 1000 cycles. We discussed the influence of fermented glucose and indicated that the room temperature fermentation method can enhance the effect of carbon modification on catalyst activity, which further enhances the performance and stability of C-NiFe(BP) in OER. Combining common fermentation processes in life with scientific research to better enhance the performance of catalysts and improve scientific research methods. This work provides an innovative approach on the synthesis of stable C-modified a-NiFe alloy catalysts and further promotes the development of high-performance OER catalysts.

Transition metal oxides (TMOs) have been thought of potential anodic materials for lithium-ion batteries (LIBs) owing to their intriguing properties. However, the limited conductivity and drastic volume change still hinder their practical applications. Herein, a metal oxyacid salts-confined pyrolysis strategy is proposed to construct hierarchical porous metal oxide@carbon (MO@C, MO = MoO₂, V₂O₅, and WO₃) composites for solving the aforementioned problems. A water-evaporation-induced self-assembly mechanism has been put forward for fabricating the MO@polyvinyl pyrrolidone (PVP)@SiO₂ precursors. After the following pyrolysis and etching process, small MO nanoparticles can be successfully encapsulated in the hierarchical porous carbon framework. Profiting from the synergistic effect of MO nanoparticles and highly conductive carbon framework, MO@C composites show excellent electrochemical properties. For example, the as-obtained MoO₂@C composite exhibits a large discharge capacity (1513.7 mAh·g⁻¹ at 0.1 A·g⁻¹), good rate ability (443.5 mAh·g⁻¹ at 5.0 A·g⁻¹), and supernal long-lived stability (669.1 mAh·g⁻¹ after 1000 cycles at 1.0 A·g⁻¹). This work will inspire the design of novel anode materials for high-performance LIBs.

Solar thermal interfacial water evaporation is proposed as a promising route to address freshwater scarcity, which can reduce energy consumption and have unlimited application scenarios. The large semiconductor family with controllable bandgap and good chemo-physical stability are considered as good candidates for photo-evaporation. However, the evaporation rate is not satisfactory because the rational control of nano/micro structure and composition is still in its infancy stage. Herein, by systemically analyzing the photo-thermal evaporation processes, we applied the hollow multishelled structure (HoMS) into this application. Benefiting from the multishelled and hierarchical porous structure, the light absorption, thermal regulation, and water transport are simultaneously optimized, resulting in a water evaporation rate of 3.2 kg·m⁻²·h⁻¹, which is among the best performance in solar-vapour generation. The collected water from different water resources meets the World Health Organization standard for drinkable water. Interestingly, by using the CuO/Cu₂O system, reactive oxygen species were generated for water disinfection, showing a new route for efficient solar-vapour generation and a green way to obtain safe drinking water.