Wuhan University

About: Wuhan University is a education organization based out in Wuhan, China. It is known for research contribution in the topics: Population & Feature extraction. The organization has 92849 authors who have published 92882 publications receiving 1691049 citations. The organization is also known as: WHU & Wuhan College.

Electron density modulation of NiCo2S4 nanowires by nitrogen incorporation for highly efficient hydrogen evolution catalysis.

Abstract: Metal sulfides for hydrogen evolution catalysis typically suffer from unfavorable hydrogen desorption properties due to the strong interaction between the adsorbed H and the intensely electronegative sulfur. Here, we demonstrate a general strategy to improve the hydrogen evolution catalysis of metal sulfides by modulating the surface electron densities. The N modulated NiCo2S4 nanowire arrays exhibit an overpotential of 41 mV at 10 mA cm−2 and a Tafel slope of 37 mV dec−1, which are very close to the performance of the benchmark Pt/C in alkaline condition. X-ray photoelectron spectroscopy, synchrotron-based X-ray absorption spectroscopy, and density functional theory studies consistently confirm the surface electron densities of NiCo2S4 have been effectively manipulated by N doping. The capability to modulate the electron densities of the catalytic sites could provide valuable insights for the rational design of highly efficient catalysts for hydrogen evolution and beyond. The hydrogen evolution reaction is a promising route to produce clean hydrogen fuel; however, its efficient electrolytic generation relies on expensive platinum. Here, the authors show how modulating electron density in a metal sulfide, NiCo2S4, boosts hydrogen desorption to achieve high catalytic activity.

Multifilament Fibers Based on Dissolution of Cellulose in NaOH/Urea Aqueous Solution: Structure and Properties

Abstract: High-quality cellulose multifilaments are spun using a preliminary pilot apparatus, from the cellulose dope in an NaOH and urea aqueous solution precooled to -12 {sup o}C, by using a low-cost, simple, and environmentally friendly process. Small-angle X-ray scattering patterns indicate that the orientation of the multifilaments increase with a drawing process, leading to the improvement of their tensile strength.