15158-11-9Relevant articles and documents
Hierarchical Copper with Inherent Hydrophobicity Mitigates Electrode Flooding for High-Rate CO2 Electroreduction to Multicarbon Products
Niu, Zhuang-Zhuang,Gao, Fei-Yue,Zhang, Xiao-Long,Yang, Peng-Peng,Liu, Ren,Chi, Li-Ping,Wu, Zhi-Zheng,Qin, Shuai,Yu, Xingxing,Gao, Min-Rui
, p. 8011 - 8021 (2021/05/29)
Copper is currently the material with the most promise as catalyst to drive carbon dioxide (CO2) electroreduction to produce value-added multicarbon (C2+) compounds. However, a copper catalyst on a carbon-based gas diffusion layer electrode often has poor stability - especially when performing at high current densities - owing to electrolyte flooding caused by the hydrophobicity decrease of the gas diffusion layer during operation. Here, we report a bioinspired copper catalyst on a gas diffusion layer that mimics the unique hierarchical structuring of Setaria's hydrophobic leaves. This hierarchical copper structure endows the CO2 reduction electrode with sufficient hydrophobicity to build a robust gas-liquid-solid triple-phase boundary, which can not only trap more CO2 close to the active copper surface but also effectively resist electrolyte flooding even under high-rate operation. We consequently achieved a high C2+ production rate of 255 ± 5.7 mA cm-2 with a 64 ± 1.4% faradaic efficiency, as well as outstanding operational stability at 300 mA cm-2 over 45 h in a flow reactor, largely outperforming its wettable copper counterparts.
Theoretical and Experimental Evaluation of the Reduction Potential of Straight-Chain Alcohols for the Designed Synthesis of Bimetallic Nanostructures
Ishijima, Masanao,Matsumoto, Takatoshi,Cuya Huaman, Jhon L.,Shinoda, Kozo,Uchikoshi, Masahito,Matsuo, Kohei,Suzuki, Kazumasa,Miyamura, Hiroshi,Balachandran, Jeyadevan
, p. 9432 - 9441 (2021/05/06)
Recently, the development of bimetallic nanoparticles with functional properties has been attempted extensively but with limited control over their morphological and structural properties. The reason was the inability to control the kinetics of the reduction reaction in most liquid-phase syntheses. However, the alcohol reduction technique has demonstrated the possibility of controlling the reduction reaction and facilitating the incorporation of other phenomena such as diffusion, etching, and galvanic replacement during nanostructure synthesis. In this study, the reduction potential of straight-chain alcohols has been investigated using molecular orbital calculations and experimentally verified by reducing transition metals. The alcohols with a longer chain exhibited higher reduction potential, and 1-octanol was found to be the strongest among alcohols considered. Furthermore, the experimental evaluation carried out via the synthesis of metallic Cu, Ni, and Co particles was consistent with the theoretical predictions. The reaction mechanism of metallic particle formation was also studied in detail in the Ni-1-octanol system, and the metal ions were confirmed to be reduced via the formation of nickel alkoxide. The results of this investigation were successfully implemented to synthesize Cu-Ni bimetallic nanostructures (core-shell, wire, and tube) via the incorporation of diffusion and etching besides the reduction reaction. These results suggest that the designed synthesis of a wide range of bimetallic nanostructures with more refined control has become possible.
A Low-Temperature Molecular Precursor Approach to Copper-Based Nano-Sized Digenite Mineral for Efficient Electrocatalytic Oxygen Evolution Reaction
Chakraborty, Biswarup,Kalra, Shweta,Beltrán-Suito, Rodrigo,Das, Chittaranjan,Hellmann, Tim,Menezes, Prashanth W.,Driess, Matthias
, p. 852 - 859 (2020/02/28)
In the urge of designing noble metal-free and sustainable electrocatalysts for oxygen evolution reaction (OER), herein, a mineral Digenite Cu9S5 has been prepared from a molecular copper(I) precursor, [{(PyHS)2CuI(PyHS)}2](OTf)2 (1), and utilized as an anode material in electrocatalytic OER for the first time. A hot injection of 1 yielded a pure phase and highly crystalline Cu9S5, which was then electrophoretically deposited (EPD) on a highly conducting nickel foam (NF) substrate. When assessed as an electrode for OER, the Cu9S5/NF displayed an overpotential of merely 298±3 mV at a current density of 10 mA cm?2 in alkaline media. The overpotential recorded here supersedes the value obtained for the best reported Cu-based as well as the benchmark precious-metal-based RuO2 and IrO2 electrocatalysts. In addition, the choronoamperometric OER indicated the superior stability of Cu9S5/NF, rendering its suitability as the sustainable anode material for practical feasibility. The excellent catalytic activity of Cu9S5 can be attributed to the formation of a crystalline CuO overlayer on the conductive Cu9S5 that behaves as active species to facilitate OER. This study delivers a distinct molecular precursor approach to produce highly active copper-based catalysts that could be used as an efficient and durable OER electro(pre)catalysts relying on non-precious metals.
