Chunyong Zhang

Strain is introduced in a RuS ₂ @CoOOH heterojunction rapidly or slowly at high temperatures.Rs-RuS ₂ @CoOOH has dual-high-spin states of Co( ii ) and Co( iii ), and is superior to Ss-RuS ₂ @CoOOH that has a single high-spin state of Co( iii ).

Zinc–air batteries (ZABs) have received focused research due to their advantages such as high energy utilization and low pollution. However, the slow oxygen reduction reaction (ORR) and the high price of Pt/C catalysts severely limit the efficiency of ZABs. Therefore, the development of efficient, stable and inexpensive catalysts has become the key to the development of ZABs. In this study, we introduce Cu nanoclusters (NCs) to form coupled catalysts with FeNC catalyst, which can modulate and stabilize the geometry and electronic structure of the Fe active center during the reaction process. The Cu NCs also can promote the electron transfer of Fe atoms, thus significantly improving the electrocatalytic performance of the catalyst. The half-wave potential of the obtained Cu[ ]@FeNC catalysts reaches 0.91[ ]V and still possesses 82% activity after 60 000[ ]s durability test, which is a significant improvement over commercial Pt/C under the same conditions. When assembled into ZABs, its power density reaches 259[ ]mW cm[ ], which is significantly improved compared with the 199[ ]mW cm[ ] of the Pt/C catalyst.

PEDOT-Ag/AgCl is a highly promising material with dual functions of hydrogen evolution reaction (HER) and supercapacitors. In this study, a simple low-temperature stirring and light irradiation method was used to synthesize PEDOT-Ag/AgCl on the surface. Then, PEDOT-Ag/AgCl was analyzed using X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. PEDOT-Ag/AgCl reacted in 1 M KOH alkaline electrolyte with an overpotential of 157 mV at 20 mA·cm⁻² and a Tafel slope of 66.95 mv·dec⁻¹. Owing to the synergistic effect of PEDOT and Ag/AgCl, this material had a small resistance (1.7 Ω) and a large specific capacitance (978 F·g⁻¹ at current density of 0.5 A·g⁻¹). The synthesis method can prepare nanostructured PEDOT with uniformly-distributed Ag nanoparticles and rod-shaped AgCl on the surface, which can be used as both HER electrocatalysts and supercapacitor electrodes.

Single-atom catalysts anchored to oxide or carbonaceous substances are typically tightly coordinated by oxygen or heteroatoms, which certainly impact their electronic structure and coordination environment, thereby affecting their catalytic activity. In this study, we prepared a stable oxygen evolution reaction (OER) catalyst on tungsten carbide using a simple pyrolysis method. The unique structure of tungsten carbide allows the atomic RuNi catalytic site to weakly bond to the surface W and C atoms. XRD patterns and HRTEM images of the WCx-RuNi showed the characteristics of phase-pure WC and W₂C, and the absence of nanoparticles. Combined with XPS, the atomic dispersion of Ru/Ni in the catalyst was confirmed. The catalyst exhibits excellent catalytic ability, with a low overpotential of 330 mV at 50 mA/cm² in 1 m KOH solutions, and demonstrates high long-term stability. This high OER activity is ascribed to the synergistic action of metal Ru/Ni atoms with double monomers. The addition of Ni increases the state density of WCx-RuNi near the Fermi level, promoting the adsorption of oxygen-containing intermediates and enhancing electron exchange. The larger proximity of the d band center to the Fermi level suggests a strong interaction between the d electrons and the valence or conduction band, facilitating charge transfer. Our research offers a promising avenue for reasonable utilization of inexpensive and durable WCx carrier-supported metal single-atom catalysts for electrochemical catalysis.

In this work, a Ni_xCo_x/Silk-PVDF bimetallic catalyst electrode was prepared for the hydrogen evolution reaction (HER) in hydropower. This cheap, durable, and efficient electrode has good practical application prospects. Green natural silk, which will pollute the environment. The electrodes (obtained by varying the Ni:Co ratio and hydrothermal times) were prepared hydrothermally. Ni and Co elements were revealed by X-ray diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy. Ni₂Co₂/silk-PVDF was identified as an effective catalyst in 1 M KOH alkaline electrolyte with an overpotential of 89.4 mV at 20 mA cm⁻² and a Tafel slope of 47.46 mv dec⁻¹. It showed low resistance and a high specific surface area in EIS and CV tests, respectively, proving its superior HER performance. Finally, the stability and durability of the electrode coated with PVDF were demonstrated via testing at a voltage of −0.1 V over 24 h. This work provides an environmentally friendly and simple method to load metal on a self-supporting electrode to be used in the hydrogen evolution reaction.

Iron levels are closely related to animals' growth performance and anti-oxidant function. Lactoferrin (LF) is an iron-binding glycoprotein, which can promote the absorption of iron and regulate immune function. This study aimed to clarify the effect of maternal LF supplementation on the iron metabolism of Dahe piglets. Sixty sows (Dahe black, parity 3-4, no significant differences in body weight) were randomly assigned to five groups: control (basal diet with no iron supplementation), supplemented 100 (LF1 group), 200 (LF2 group), or 300 (LF3 group) mg LF/kg in the basal diet, and the basal diet supplemented with 100 (Fe-Gly group) mg Fe/kg as ferrous glycine (Fe-Gly). The serum anti-oxidant parameters of the sows and neonatal piglets were determined. The iron contents, anti-oxidant gene expression levels, and Fe-acquisition genes were detected in the liver, heart, spleen, and other neonatal organs. The results indicated that (1) the LF3 group of sows had the highest serum and colostrum iron contents (P< 0.05). The maternal LF significantly promoted the iron stores in the heart, liver, spleen, and lung of piglets compared with Fe-Gly. (2) The maternal LF increased serum glutathione peroxidase (GSH-Px) and total superoxide dismutase (T-SOD) activities of sows. Compared with other groups, the total anti-oxidant capacity (T-AOC) activity of LF2 groups increased significantly (P< 0.05). (3) LF significantly increased piglet serum GSH-Px, T-SOD, and T-AOC activities (P< 0.05). (4) Gene expression levels of GSH-Px, and SOD in the duodenum and jejunum of the LF2 group were significantly higher than in the Fe-Gly group (P< 0.05), while the expression levels in the liver and heart were lower (P< 0.05). (5) The expression levels of hepcidin and LF in the liver and duodenum of the LF2 group were significantly higher than in the Fe-Gly group (P< 0.05). In conclusion, maternal LF supplementation showed remarkable effects on iron storage in neonatal piglets, and exhibited strong antioxidant activities, it is helpful to prevent the occurrence of iron deficiency, and improves the immune function of animals.

Binary transition metal oxides exhibit improved properties including good redox potentials and electrical conductivities compared with single metal oxides as electrode materials in energy storage. Herein, ZIF-67 is prepared by a one-step method using Co²⁺ as the central metal ion, 2-methylimidazole as the organic ligand, and methanol as an organic solvent at room temperature. Hollow NiCo₂O₄ and sheet-like Co₃O₄/NiCo₂O₄ derived from bimetallic imidazolate framework precursors were synthesized by adding cobalt and nickel ions in appropriate proportions. A hollow and porous structure is achieved for the reaction between a nickel salt and ZIF-67, and this unique nanostructure provides a high active surface area, which is beneficial to the electrochemical properties. Several samples are prepared and used as electrode materials for electrochemical tests in 6 M KOH. As a result, the Co₃O₄/NiCo₂O₄ electrode with a sheet nanostructure showed a high specific capacitance of 846 F g⁻¹ at a current density of 0.5 A g⁻¹. This Co₃O₄/NiCo₂O₄ electrode material is promising for future studies on high-performance supercapacitors to solve emerging energy-related problems. [ ]

A new MoS₂/TiSi₂ complex catalyst was designed and synthesized by a simple one-step in situ photo-assisted reduction procedure. The structural and morphological properties of the composites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and ultraviolet-visible diffused reflectance spectroscopy (UV-vis DRS), which proved the formation of MoS₂/TiSi₂. MoS₂/TiSi₂ with optimized composition showed obviously enhanced photocatalytic activity and superior durability for water reduction to produce H₂. The H₂ generation rate over the MoS₂/TiSi₂ photocatalyst containing 3 wt % MoS₂ reached 214.1 μmol·h⁻¹·g⁻¹ under visible light irradiation, which was ca. 5.6 times that of the pristine TiSi₂. The improved photocatalytic activity of MoS₂/TiSi₂ could be related to the broad response spectrum, large visible light absorption, and synergies among MoS₂ and TiSi₂ that enhance photoexcited charge transfer and separation.