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The development of mechanically robust and electrochemically active high-performance electrodes is essential for the electrocatalytic process, thus reducing the energy input and achieving excellent environmental tolerance. In this case, high-entropy alloys, as a rising star with excellent mechanical stability and electrochemical performance, can be applied as both structural and functional electrodes in the field of conversion and storage. Herein, a high-entropy alloy electrode with hierarchically porous structure (PHEA) was designed and fabricated via the selective etching of a eutectic two-phase microstructure. Compared with commercial nickel foam (NF) as an electrocatalyst substrate, PHEA possessed better mechanical robustness, larger specific surface area, more favorable electrocatalytic activity and long-term stability. Subsequently, a surface modification strategy was proposed to decorate the PHEA substrate via a facile noble-metal-doped-layered double hydroxide (LDH) regulating route. Electrochemical measurements showed that the PHEA electrode modified with trace-noble-metal-doped-LDH exhibited excellent catalytic activity and stability, with overpotentials of 21 and 227 mV at a current density of 10 mA cm−2 for the hydrogen evolution (HER) and oxygen evolution reaction (OER), respectively. The X-ray photoelectron spectra and in situ FT-IR spectra indicated that the successful doping of Pt contributed to the enhancement in the HER performance, and the in situ Raman spectra revealed the structural transformation on the catalyst surface during the OER process. Surprisingly, long-term stability at an ultrahigh industrial-level current density (∼1 A cm−2) was observed when employing the bifunctional LDH@PHEA electrode assembly in an overall water splitting device. This work explored the advantages and application of PHEA as a versatile electrocatalyst substrate, thus providing new insights and approaches for designing and constructing robust porous electrodes via surface modification towards efficient hydrogen generation. [ABSTRACT FROM AUTHOR]

BACKGROUND: Spleen deficiency syndrome (SDS) is associated with elevated inflammatory factors and dysregulation of gastrointestinal motility hormones and intestinal microbiota. Qushi decoction (QD), a traditional formula, has not been reported using modern scientific research methods for changes in its probiotic fermented QD (FQD) composition and its potential mechanisms to alleviate SDS. Therefore, the aim of this study was to investigate the splenic protection of FQD in SDS rats by modulating gastrointestinal motility hormones and intestinal microbiota. RESULTS: The results showed that FQD increased total polysaccharides, total protein, total flavonoids and the other active ingredients compared to QD, effectively improved splenic inflammation and apoptosis in SDS rats, and modulated gastrointestinal motility hormones to alleviate diarrhea and other symptoms. In addition, the dysregulation of the gut microbiota was reversed by increasing the levels of Bifidobacterium and decreasing the levels of Escherichia–Shigella and Proteobacteria, which may be related to the regulation of bacterial metabolites to alleviate SDS. CONCLUSION: These results suggest that FQD is an effective formula for improving SDS. Our findings show that FQD beneficial to the implications for the treatment of SDS. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Zero or negative emissions of carbon dioxide (CO2) is the need of the times, as inexorable rising and alarming levels of CO2 in the atmosphere lead to global warming and severe climate change. The electrochemical CO2 reduction (eCO2R) to value‐added fuels and chemicals by using renewable electricity provides a cleaner and more sustainable route with economic benefits, in which the key is to develop clean and economical electrocatalysts. Carbon‐based catalyst materials possess desirable properties such as high offset potential for H2 evolution and chemical stability at the negative applied potential. Although it is still challenging to achieve highly efficient carbon‐based catalysts, considerable efforts have been devoted to overcoming the low selectivity, activity, and stability. Here, we summarize and discuss the recent progress in carbon‐based metal‐free catalysts including carbon nanotubes, carbon nanofibers, carbon nanoribbons, graphene, carbon nitride, and diamonds with an emphasis on their activity, product selectivity, and stability. In addition, the key challenges and future potential approaches for efficient eCO2R to low carbon‐based fuels are highlighted. For a good understanding of the whole history of the development of eCO2R, the CO2 reduction reactions, principles, and techniques including the role of electrolytes, electrochemical cell design and evaluation, product selectivity, and structural composition are also discussed. The metal/metal oxides decorated with carbon‐based electrocatalysts are also summarized. We aim to provide insights for further development of carbon‐based metal‐free electrocatalysts for CO2 reduction from the perspective of both fundamental understanding and technological applications in the future. [ABSTRACT FROM AUTHOR]

Cu-based catalysts are exceptionally advantageous for the electrochemical CO2 reduction reaction (CO2RR) to fuels and chemical products utilizing clean and renewable energy. However, most tend to yield a diversity of hydrocarbon products along with the H2 evolution side reaction. We reveal how a 3D core–shell porous-structured Cu@Sn hybrid electrode can lead to an unprecedented selective CO2 electroreduction to HCOO−. Such an advantageous architecture is assembled via an in situ electrodeposition protocol using a dynamic hydrogen bubble template, rendering an enlarged electrode surface area when evaluated as an electrode material for the CO2RR. Notably, the best performing electrode, i.e., Cu@Sn(1), achieved a reduction current density of 55 mA cm−2 at −1.33 V vs. RHE, and an extremely encouraging Faradaic efficiency of 100% at an applied potential −0.93 V vs. RHE, accompanied by a partial current density of 16.52 mA cm−2. Moreover, it manifested a remarkably stable operation for over 15 hours of continuous electrolysis in aqueous KHCO3 solution. Numerically solving mass transfer equations and the Butler–Volmer equation show how the optimized presence of granular structured Sn on the surface of Cu was found to be the key for enhancing the HCOO− selectivity and the mass activity. [ABSTRACT FROM AUTHOR]

Abstract: Zinc‐air batteries are expected to be ideal energy storage devices, showing features of high energy density, economic viability, and safety. To design such a system, it is necessary to develop active and durable electrocatalysts to catalyze the slow oxygen reduction reaction (ORR) during discharging and the oxygen evolution reaction (OER) during charging. In this study, a composite bifunctional catalyst (Co3O4@CNT@MC‐200) for use in zinc‐air batteries is prepared through a simple sol‐gel method, which combines Co3O4 with carbon nanotubes (CNTs) and mesoporous carbon (MC). Benefiting from its large specific surface area and, thus, a multitude of active sites, the Co3O4@CNT@MC‐200 composite bifunctional electrocatalyst shows excellent ORR performance in 0.1 M KOH, resulting in a half‐wave potential (E1/2) of 0.72 V and limiting diffusion current of 4.6 mA cm−2. In zinc‐air battery tests, a high discharge peak power density of 267 mW cm−2 and robust lifetime of 8700 min without attenuation is observed. Moreover, the physical properties of the reported catalyst were characterized. This study allows us to envisage the design of highly efficient composite electrocatalysts for zinc‐air batteries and a variety of other energy applications. [ABSTRACT FROM AUTHOR]

Abstract: The front cover artwork is provided by Prof. Jinli Qiao's research group from Donghua University (China). The image shows an as‐prepared composite material consisting of Co3O4 with two carbon materials [i.e. carbon nanotubes (CNTs) and mesoporous carbon] with excellent oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) performance. The composite shows great potential and practical implementation for rechargeable energy devices in electric vehicles are envisioned. Read the full text of the Article at 10.1002/celc.201800159. [ABSTRACT FROM AUTHOR]