Publications by authors named "Huazhang Zhai"

Double-atom catalysts (DACs) with asymmetric coordination are crucial for enhancing the benefits of electrochemical carbon dioxide reduction and advancing sustainable development, however, the rational design of DACs is still challenging. Herein, this work synthesizes atomically dispersed catalysts with novel sulfur-bridged Cu-S-Ni sites (named Cu-S-Ni/SNC), utilizing biomass wool keratin as precursor. The plentiful disulfide bonds in wool keratin overcome the limitations of traditional gas-phase S ligand etching process and enable the one-step formation of S-bridged sites.

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We propose an innovative preparation method, namely, a two-step pyrolysis process, to synthesize Zn-Co bimetallic catalysts with excellent hydrogen evolution performance. In the synthesized ZnCo-SNC catalyst, there exists a strong interaction between Zn and Co, along with synergistic effects with S/N atoms, collectively promoting the stability of the catalyst structure. Experimental results demonstrate that the overpotential of this catalyst at 10 mA cm current density is only 49 mV, and it maintains excellent hydrogen evolution performance even after 5000 cycles.

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Efficient and sustainable energy development is a powerful tool for addressing the energy and environmental crises. Single-atom catalysts (SACs) have received high attention for their extremely high atom utilization efficiency and excellent catalytic activity, and have broad application prospects in energy development and chemical production. M-N is an active center model with clear catalytic activity, but its catalytic properties such as catalytic activity, selectivity, and durability need to be further improved.

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Nanozymes with high activity and stability have emerged as a potential alternative to natural enzymes in the past years, but the relationship between the electronic metal-support interactions (EMSI) and catalytic performance in nanozymes still remains unclear. Herein, a copper nanoparticle nanozyme supported on N-doped TiCT (Cu NPs@N-TiCT) is successfully synthesized and the modulation of EMSI is achieved by introducing N species. The stronger EMSI between Cu NPs and TiCT, involving electronic transfer and an interface effect, is revealed by X-ray photoelectron spectroscopy, soft X-ray absorption spectroscopy, and hard X-ray absorption fine spectroscopy at the atomic level.

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The regulation of the coordination environment of the central metal atom is considered as an alternative way to enhance the performance of single-atom catalysts (SACs). Herein, we design an electrocatalyst with active sites of isolated Co atoms coordinated with four sulfur atoms supported on N-doped carbon frameworks (Co-S/NC), confirmed by high-angle annular dark-field scanning transmission electron microscope (HADDF-STEM) and synchrotron-radiation-based X-ray absorption fine structure (XAFS) spectroscopy. The Co-S/NC possesses higher hydrogen evolution reaction (HER) catalytic activity than other Co species and exceptional stability, which exhibits a small Tafel slope of 60 mV dec and a low overpotential of 114 mV at 10 mA cm during the HER in 0.

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In the present work, mesoporous NiCo2O4 hollow nanocubes are synthesized using a "coordinating etching & precipitating" (CEP) route. The hollow nanocubes are characterized using SEM, TEM, XRD, XPS and BET methods. The hollow nanocubes have a uniform morphology of 300-500 nm, a high surface area of 134.

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The rational design and fabrication of SnO2-based anode materials could offer a powerful way of effectively alleviating their large volume variation and guaranteeing excellent reaction kinetics for electrochemical lithium storage. Herein, we present an ultrarapid, low-cost, and simple microwave-assisted synthesis of ultrathin SnO2 nanosheets at the gram-scale. The two-dimensional (2D) anisotropic growth depends on microwave dielectric irradiation coupled with surfactant structural direction, and is conducted under low-temperature atmospheric conditions.

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