Henan Normal University

About: Henan Normal University is a education organization based out in Xinxiang, China. It is known for research contribution in the topics: Catalysis & Ionic liquid. The organization has 10863 authors who have published 11077 publications receiving 166773 citations.

Highly efficient and durable aqueous electrocatalytic reduction of CO2 to HCOOH with a novel bismuth–MOF: experimental and DFT studies

Abstract: Electrochemical reduction of carbon dioxide (ERCO2) to low-carbon fuel and useful chemicals, which can simultaneously store renewable energy and recover CO2 in a green manner, has proven to be a viable energy storage and conversion strategy. However, there is always a technical bottleneck in preparation of highly active, selective and stable catalysts. In this work, we hydrothermally synthesized a new type of bismuth-based organic framework (Bi–MOF) and carefully investigated it as the catalyst for ERCO2. All the samples exhibited excellent performance and the optimized one (i.e. Bi-BTC-D) achieved a high formate Faraday efficiency (FE) up to 95.5% at −0.86 VRHE and a current density of −11.2 mA cm−2. Moreover, the FE has been maintained over 90.0% after 12 hours of continuous electrolysis without significant reduction. The measurement results demonstrated that the excellent performance can be attributed to the special structure of Bi-BTC-D. DFT calculations show that the Bi site of Bi-BTC-D is highly efficient for formate production with very low overpotentials. The great potential of using a Bi–MOF as a highly stable, molecularly tunable catalytic material for ERCO2 is confirmed.

New Copper(I)/DBU Catalyst System for the Carboxylative Cyclization of Propargylic Amines with Atmospheric CO2: An Experimental and Theoretical Study

Abstract: Carbon dioxide (CO2) is an abundant and renewable feedstock for the production of high-value chemicals. Herein, CuI and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) were employed as an efficient catalyst system to synthesize 2-oxazolidinones through the coupling reaction of CO2 and propargylic amines. It was found that this cost-competitive catalyst system could efficiently catalyze the reaction within only 4 h at atmospheric pressure CO2, and a wide range of substrates were suitable for this reaction. Various target products were obtained in excellent yields. Furthermore, the catalytic mechanism of the CuI/DBU system was investigated by using density functional theory. It was shown that copper(I) and DBU played synergistic roles in activating both the C≡C triple bond and the amino group of propargylic amines in the reaction.

Apple pectin-mediated green synthesis of hollow double-caged peanut-like ZnO hierarchical superstructures and photocatalytic applications

Abstract: Hollow ZnO superstructures have potential technological applications. With this motivation, a simple approach is developed to prepare hollow double-caged peanut-like ZnO hierarchical superstructures with the assistance of apple pectin. The biotemplate-assisted approach concurs with “green” chemistry as it is simple and environmentally friendly. The products are characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results reveal that the pectin-directed hydrothermal process is essential to obtain the final products. The morphologies and dimensions of the ZnO structures could be easily tuned by varying the molar ratios of the pectin to zinc ion, the amount of ammonia, the reaction time and the temperature. A possible formation mechanism for the hollow superstructures is described. In addition, the optical properties of the ZnO superstructures were investigated in some detail. The as-prepared samples showed high photocatalytic activity towards methyl orange (MO) under ultraviolet (UV) irradiation.