Highly efficient and low-cost catalysts for water electrolysis are crucial for the advancement of clean energy. In this study, an innovative hydrogen evolution reaction (HER) catalyst is synthesized, which consists of Ni and NiMoN nanoparticles coated by nitrogen-doped carbon layers and grown on a black pearl carbon substrate (denoted as NC@NiMoN NPs/BPC). The double carbon design-comprising a surface carbon coating layer and a bottom carbon substrate-modulates the electronic structure of NiMoN and facilitates the uniform dispersion of NiMoN NPs on BPC, endowing this hierarchical electrocatalyst with high activity and long durability. The electrochemical specific surface area of NC@NiMoN NPs/BPC is 42 times larger than that of NC@NiMoN without the BPC substrate. Moreover, this catalyst exhibits superior HER performance with low overpotentials of 11.3 and 74.6 mV at 10 and 100 mA cm(-2), respectively, outperforming the commercial Pt/C catalyst. Additionally, a typical alkaline water electrolyzer equipped with the NC@NiMoN NPs/BPC cathode shows negligible voltage decay after 250 h of continuous electrolysis, indicating excellent stability. This work provides not only an efficient hydrogen evolution electrocatalyst but also an innovative double-carbon strategy for the construction of efficient electrocatalysts for HER in water electrolysis.

Efficient and stable non-precious metal catalysts for hydrogen evolution reaction (HER) are important for developing the industrial-scale production of green hydrogen via alkaline water electrolysis (AWE). This work reports a hierarchical core-shell Ni-Mo2N@Ni/C nanorod catalyst protected by a carbon layer, featuring external nanosheet arrays and internal nanowires. The unique hierarchical architecture not only promotes mass transfer and bubble detachment but also provides abundant active sites, thus effectively improving the HER activity of the catalyst. The Ni-Mo2N@Ni/C exhibited an impressive overpotential of only 11 mV at 10 mA cm-2, along with a low Tafel slope of 45.9 mV dec-1. Moreover, the dense nanosheet arrays significantly enhance the mechanical robustness of the nanorods on the substrate and create a protective barrier to suppress the oxidation and dissolution of active components, further improving the stability of Ni-Mo2N@Ni/C. Under industrial AWE conditions (30 wt% KOH, 85 degrees C), the electrolyzer employing an Ni-Mo2N@Ni/C cathode and a commercial NiFe anode required a voltage of only 1.698 V to achieve a high current density of 1 A cm-2, and showed no degradation over 1000 h of operation under fluctuating current and temperature. This study provides an effective strategy for designing highly active and stable non-precious HER catalysts for industrial applications.

Water oxidation is a crucial reaction in alkaline water electrolysis (AWE) technology, in which the development of highly active and durable electrocatalysts for oxygen evolution reaction (OER) remains a great challenge. Herein, electrochemical etching method is employed to reconstruct commercial nickel-iron foam (NFF) substrate in the presence of WO42- and Cl- for in situ growth of the NiFeW composite (oxy)hydroxide nanoflakes-assembled microspheres to obtain a superb electro-catalyst NiFeW/NFF electrode. Promoted by the W-induced electronic rearrangement effect, abundant defects and high surface area, the NiFeW/NFF exhibits lower OER overpotential (243 mV@10 mAcm(-2)) than the RuO2-IrO2 commercial electrode in 1 M KOH. In a practical AWE application, the NiFeW/NFF displays robust OER stability with a voltage decay percentage <1 % in a 500-hour test of water electrolysis. The cell voltages of NiFeW/NFF assembled electrolyzer are only 1.852 V@8000 Am(-2) at 70 degrees C and 1.869 V@3000 Am(-2) at low temperature of 27 degrees C under fluctuating conditions. Interestingly, it is disclosed that the sacrificial process of W occurs spontaneously during the OER process and abundant O-Vacancies (Ov) and Ni/FeOOH active sites are in-situ generated to improve OER performance. This work highlights an in-situ electrochemical reconstruction strategy of W doping/leaching to fabricate a highly active and durable OER electrocatalyst with abundant Ov for OER.

Direct air carbon dioxide capture (DAC) is one of the promising ways to alleviate the increased carbon dioxide concentration in the atmosphere. Inorganic alkaline (KOH, NaOH, etc.) solutions, with strong alkalinity and low cost, are regarded as efficient absorbents for low-concentration CO2 in air. To efficiently regenerate KOH from the K2CO3/KHCO3 solution, the ion-selective membrane electrolysis method has attracted concern in recent years, which generates both high-concentration KOH solution and H-2 simultaneously. In order to reduce the cell voltage of the K2CO3/KHCO3 electrolysis, the present paper proposes a two-step process of hydrothermal treatment and annealing to fabricate a heterojunction electrocatalyst with Ni nanoparticles in situ anchored on MoO2 micropillars. In the prepared Ni NPs/MoO2 MPs heterojunction catalyst, MoO2 promotes the dissociation of the adsorbed water molecules and optimizes the H adsorption on the adjacent Ni active site. As a result, the Ni NPs/MoO2 MPs catalyst shows an extremely low overpotential of 13 mV at 10 mA cm(-2) in 1 M KOH and negligible performance deterioration after 100 h of electrolysis at 300 mA cm(-2), and 1000 CV cycles. Moreover, the electrolysis cell with Ni NPs/MoO2 MPs cathode for electrolysis of carbonate solution achieves a high cathode current efficiency (>97 %) to generate high concentration KOH (6.9 M) solution, and a cell voltage of 2.69 V at 200 mA cm(-2), showing a superior performance to that of the precious Pt/C electrode-based cell. This non-precious Ni NPs/MoO2 MPs electrocatalyst shows promising prospects for highly efficient electrolysis of K2CO3 to generate H-2 and KOH.

Green hydrogen via renewable-powered electrolysis is vital for decarbonization, yet OER anode scalability remains a key limitation. A comparison of ALK, PEM, AEM, and SOEC technologies reveals challenges in dynamic integration. Lab-to-industrial translation suffers from mass/heat transfer and stability constraints. Understanding fluctuating operation–induced degradation is critical. Future advances demand co-design of materials, interfaces, and systems to bridge performance gaps and enable sustainable, large-scale deployment.

Water electrolysis powered by renewable energy is widely regarded as one of the most important methods for large-scale green hydrogen production. In this work, we have prepared a high-valence gallium-doped nickel-molybdenum nitride nanocomposite (Ga-Ni/Mo3N2@C) with abundant heterojunctions by a co-precipitation step and a subsequent high-temperature treatment step. The produced Ga-Ni/Mo3N2@C material benefits from a dual modification strategy (DMS) including the Ga doping-induced internal electronic construction and the carbon shell encapsulation-derived external corrosion inhibition. This DMS not only facilitates the modulation of the intrinsic activity of Ni and Mo constituents, but also strengthens the durability of the Ni/Mo3N2 active components. In hydrogen evolution reaction (HER) test, Ga-Ni/Mo3N2@C exhibits ultra-low over-potentials of 9 mV at 10 mA cm-2 and 116 mV at 100 mA cm-2, small Tafel slope of 41.2 mV dec-1, high conductivity of 114.8 mu S cm-1 and low charge transfer resistance of 0.729 Omega cm2. Moreover, the Ga-Ni/ Mo3N2@C electrocatalyst exhibits an ultralow Arrhenius activation energy of 14.69 kJ mol-1, lower than those of Ni/Mo3N2 (20.78 kJ mol-1), commercial Raney Ni (41.40 kJ mol-1) and Pt/C catalyst (15.24 kJ mol-1). The Ga-Ni/Mo3N2@C-assembled electrolyzer exhibits a lower cell voltage of 1.80 V than the counterpart cells with commercial Raney Ni (2.05 V) cathode or Ni/Mo3N2 (1.85 V) cathode at 3000 A m-2 and room temperature, showing negligible deterioration in performance. The utilization of high-valence Ga atoms doping and carbon shell protection effect not only modulates material electronic structure to accelerate reaction kinetics, but also inhibits the dissolution of active sites. It is believed that this study offers a novel strategy for the development of high-performance electrocatalysts in water electrolysis.

This study presents a W-doped NiMoN microcolumn with a nitrogen-doped carbon layer as an efficient electrocatalyst. The W doping and carbon layer enhance its stability and antioxidant properties, making it suitable for renewable energy applications.

Water-splitting is a critical technology for the conversion and storage of renewable energy. The slow anodic process dynamics with high overpotential greatly limit the commercialization of electrolytic hydrogen production. Herein, we proposed an electrochemical in situ etching method to achieve molybdenum component-controlled dissolution of ultrathin NiFeMo layered double hydroxides (LDHs) nanosheet arrays on nickel-iron foam (NFF) to create in situ reconstructed oxygen evolution reaction (OER) active sites in LDHs. The Mo-etched material exhibited significantly enhanced catalytic performance and demonstrated exceptional OER activity in alkaline media, achieving a low overpotential of 288 mV at 10 mA cm-2 and 784 mV at 1000 mA cm-2, along with a desired Tafel slope of 43.52 mV dec-1. The enhanced reaction kinetics was contributed by Mo doping-induced electronic structure optimization and interfacial stabilization. Furthermore, an assembled alkaline electrolyzer with NiFeMo/NFF maintained a stable electrolysis voltage (1.695 ± 0.022 V) under simulated industrial fluctuating conditions (30 wt% KOH, 85 °C, 3000 A m-2) for 210 h, exhibiting a super-low voltage decay rate (0.1 mV h-1). The superior performance-stability properties of the new catalyst displayed new material design strategies for efficient industrial hydrogen-production systems.

Sustainable water electrolysis powered by renewable energy requires cost-efficient, effective, and robust catalysts. This study utilizes NiMoFeO and its nitrogen-doped carbon-coated (NC) derivatives NiMoFe@NC, as advanced OER and HER catalysts, respectively. The derivative fabrication not only simplifies catalyst synthesis but also notably enhances the stability of the HER catalyst through carbon coating. The outstanding OER performance of NiMoFeO is attributed to high-valence metals, while the enhanced HER activity of NiMoFe@NC arises from synergies effect from NiFe and MoO2. At 10 mA cm- 2, NiMoFeO showcased a low OER overpotential of 197 mV, and NiMoFe@NC displayed an extremely low HER overpotential of 8 mV. At 100 mA cm- 2 and 27 degrees C, the NiMoFeO(+)//NiMoFe@NC(-) exhibited a voltage of 1.69 V, outperforming the RuO2(+)//Pt/C (-) (1.77 V). Notably, over 1000 cycles of repetitive ON/OFF electrolysis, the voltage of NiMoFeO(+)//NiMoFe@NC(-) merely increased 0.01 V, confirming the exceptional potential of these catalysts for hydrogen production compatible with renewable energy.

Hydrogen production through alkaline water electrolysis holds great promise as a scalable solution for renewable energy storage and conversion. The development of non-precious metal-based electrocatalysts with low-overpotential for alkaline water electrolysis is essential to decrease the cost of electrolysis devices. Although the Ni-based and Fe-based electrocatalysts have been commercially employed in the cathodic hydrogen evolution reaction (HER) and anodic oxygen evolution reaction (OER), it is imperative to persistently pursue the advancement of highly efficient electrocatalysts with enhanced current density and fast kinetics. This feature article overviews the progress of NiMo HER cathodes and NiFe OER anodes in the traditional alkaline water electrolysis process for hydrogen production, including the detailed mechanisms, preparation strategies, and structure-function relationship. Moreover, recent advances of Ni-based and Fe-based electrodes in the process of novel alkaline water electrolysis, involving small energetic molecule electro-oxidation and redox mediator decoupled water electrolysis, are also discussed for hydrogen production with low cell voltage. Finally, the perspective of these Ni-based and Fe-based electrodes in the mentioned electrolysis processes is proposed.

以FTO镀层电极为基体,经电沉积制得BiOI镀层后化学法转化得到BiVO4电极,并以BiVO4电极为阳极催化水分子发生二电子氧化过程产生过氧化氢.研究结果表明,碳酸氢盐作为电解质溶液时,对过氧化氢的产生有促进作用.测定结果表明,在2 mol·L-1 KHCO3溶液中,在3.39 V(vs RHE)阳极电位下电解,则过氧化氢的生成速率最高,达到3.73×10-7 mol·cm-2·min-1;在3.19 V(vs RHE)阳极电位下电解,则电流效率最高达到10.13％;电极连续使用寿命达到240 min以上.

就业工作是高校重点工作,后疫情时期高校就业工作面临新形势和新挑战.笔者结合实践工作经验和数据调研,对疫情影响下如何开展"稳就业"工作提出自己的见解,就疫情对今后就业形势、 大学生就业观的影响进行浅析.同时,笔者根据北京化工大学准毕业生调研数据分析,针对性总结后疫情时期开展就业指导和帮扶工作的五个关键要点,以期对高校毕业生就业工作有所裨益.

The combination of a semiconductor heterojunction and oxygen evolution cocatalyst (OEC) is an important strategy to improve photoelectrochemical (PEC) water oxidation. Herein, a novel hamburger-like nanostructure of a triadic photoanode composed of BiVO4 nanobulks, Co3O4 nanosheets and Ag nanoparticles (NPs), that is, Ag/Co3O4/BiVO4, was designed. In our study, an interlaced 2D ultrathin p-type Co3O4 OEC layer was introduced onto n-type BiVO4 to form a p-n Co3O4/BiVO4 heterojunction with an internal electric field (IEF) in order to facilitate charge transport. Then the modification with Ag NPs can significantly facilitate the separation and transport of photogenerated carriers through the surface plasma resonance (SPR) effect, inhibiting the electron-hole recombination. The resulting Ag/Co3O4/BiVO4 photoanodes exhibit largely enhanced PEC water oxidation performance: the photocurrent density of the ternary photoanode reaches up to 1.84 mA cm-2 at 1.23 V vs. RHE, which is 4.60 times higher than that of the pristine BiVO4 photoanode. The IPCE value is 2.83 times higher than that of the pristine BiVO4 at 400 nm and the onset potential has a significant cathodic shift of 550 mV for the ternary well-constructed photoanode.

文章结合创业教育的现状,探讨了开展创业教育的重要意义,针对低年级本科生创业教育存在的问题,以北京化工大学低年级本科生为例,提出了解决方案,介绍了具体做法.以期在高校创业教育行业内部乃至全社会形成良好的创业教育氛围,推动低年级本科生创业教育的持续健康发展.