Sichuan Normal University

About: Sichuan Normal University is a education organization based out in Chengdu, Sichuan, China. It is known for research contribution in the topics: Catalysis & Fuzzy logic. The organization has 4694 authors who have published 5107 publications receiving 61245 citations.

Cascade anchoring strategy for general mass production of high-loading single-atomic metal-nitrogen catalysts.

Abstract: Although single-atomically dispersed metal-Nx on carbon support (M-NC) has great potential in heterogeneous catalysis, the scalable synthesis of such single-atom catalysts (SACs) with high-loading metal-Nx is greatly challenging since the loading and single-atomic dispersion have to be balanced at high temperature for forming metal-Nx. Herein, we develop a general cascade anchoring strategy for the mass production of a series of M-NC SACs with a metal loading up to 12.1 wt%. Systematic investigation reveals that the chelation of metal ions, physical isolation of chelate complex upon high loading, and the binding with N-species at elevated temperature are essential to achieving high-loading M-NC SACs. As a demonstration, high-loading Fe-NC SAC shows superior electrocatalytic performance for O2 reduction and Ni-NC SAC exhibits high electrocatalytic activity for CO2 reduction. The strategy paves a universal way to produce stable M-NC SAC with high-density metal-Nx sites for diverse high-performance applications.

An efficient organocatalytic method for constructing biaryls through aromatic C–H activation

Abstract: The direct functionalization of C-H bonds has drawn the attention of chemists for almost a century. C-H activation has mainly been achieved through four metal-mediated pathways: oxidative addition, electrophilic substitution, σ-bond metathesis and metal-associated carbene/nitrene/oxo insertion. However, the identification of methods that do not require transition-metal catalysts is important because methods involving such catalysts are often expensive. Another advantage would be that the requirement to remove metallic impurities from products could be avoided, an important issue in the synthesis of pharmaceutical compounds. Here, we describe the identification of a cross-coupling between aryl iodides/bromides and the C-H bonds of arenes that is mediated solely by the presence of 1,10-phenanthroline as catalyst in the presence of KOt-Bu as a base. This apparently transition-metal-free process provides a new strategy with which to achieve direct C-H functionalization.

Self-Templated Fabrication of MoNi4/MoO3-x Nanorod Arrays with Dual Active Components for Highly Efficient Hydrogen Evolution

Abstract: A binder-free efficient MoNi4 /MoO3-x nanorod array electrode with 3D open structure is developed by using Ni foam as both scaffold and Ni source to form NiMoO4 precursor, followed by subsequent annealing in a reduction atmosphere. It is discovered that the self-templated conversion of NiMoO4 into MoNi4 nanocrystals and MoO3-x as dual active components dramatically boosts the hydrogen evolution reaction (HER) performance. Benefiting from high intrinsic activity, high electrochemical surface area, 3D open network, and improved electron transport, the resulting MoNi4 /MoO3-x electrode exhibits a remarkable HER activity with extremely low overpotentials of 17 mV at 10 mA cm-2 and 114 mV at 500 mA cm-2 , as well as a superior durability in alkaline medium. The water-alkali electrolyzer using MoNi4 /MoO3-x as cathode achieves stable overall water splitting with a small cell voltage of 1.6 V at 30 mA cm-2 . These findings may inspire the exploration of cost-effective and efficient electrodes by in situ integrating multiple highly active components on 3D platform with open conductive network for practical hydrogen production.