The large-scale application of rechargeable Zn-air batteries (ZABs) necessitates the development of high-efficiency and cost-effective bifunctional electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Herein, the density functional theory calculations were performed to reveal the charge redistribution induced by the Co/CoO heterojunction integrating with N-doped carbon, which could optimize the d-band center, thereby accelerating O transformed into OOH* in the ORR and the conversion of O* into OOH* in OER. Guided by theoretical calculations, Co/CoO hetero-nanoparticles-decorated lignin-derived N-doped porous carbon nanofibers (Co-LCFs-800) were synthesized to use as an advanced self-supported bifunctional oxygen electrocatalyst.
View Article and Find Full Text PDFWith high specific surface area, excellent polysulfide conversion activity, and fast electron/ion transfer at the interface, MXene-derived heterostructures can be employed as catalysts for lithium-sulfur (Li-S) batteries to accelerate sulfur redox kinetics and suppress shuttle effect. However, the preparation of MXene-derived heterostructures often requires high-temperature reactions, which can easily lead to the oxidation of MXene and sacrifice the electrical conductivity. Herein, a catalytic two-dimensional heterostructure (ZnS/MXene) was successfully synthesized via a mild method.
View Article and Find Full Text PDFLithium-sulfur (Li-S) batteries are known as a prospective new generation of battery systems owing to their high energy density, low cost, non-toxicity, and environmental friendliness. Nevertheless, several issues remain in the practical application of Li-S batteries, such as low sulfur usage, poor rate performance, and poor cycle stability. Ordered microporous carbon materials and carbon nanotubes (CNTs) can effectively limit the diffusion of polysulfides (LiPSs) and have high electrical conductivity, respectively.
View Article and Find Full Text PDFH- and Nb-doped ZnO (HNZO) thin films were fabricated on glass substrates with radio frequency magnetron sputtering. The effect of the flow rate of H has been investigated by analyzing the structural, optical, and electrical properties. The incorporation of H during the deposition of Nb-incorporated ZnO films significantly improved their crystallinity, conductivity, and transmittance.
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