Ni Hollow Fiber Encapsulated Bi@Zeolite for Efficient CO₂ Electroreduction

Abstract

CO2 electroreduction has attracted considerable investigations due to the desirable coupling of renewable energy utilization and value-added chemical production. However, it encounters the bottlenecks of high energy barrier and low efficiency owing to the limited CO2 solubility and mass transfer. Herein, a porous Ni hollow fiber encapsulated Bi@Zeolite catalyst was developed as a self-standing gas diffusion electrode for efficient CO2 reduction to CO. Such a delicate electrode configuration reinforces CO2 adsorption/activation on Bi@Zeolite active sites and favors mass transfer due to a shortened and directed diffusion path. These synergetic promotions induced by Bi@Zeolite encapsulated in Ni hollow fiber achieved a high CO Faradaic efficiency of 74.1% at only an overpotential of 260 mV in the ionic-liquid based electrolyte, which was 2.6 times that on the Ni foil planar configuration. In addition, both CO Faradaic efficiency and current density remained almost constant for the duration of a 16 h test, further indicating the superiority of the Ni hollow fiber encapsulated configuration. This work demonstrates the potential of using a hollow fiber to reinforce reaction kinetics for efficient CO2 electroreduction.

Application of hollow fiber electrodes for green ammonia formation

“…[85] The preparation method of Cu fibers can affect their performance leaving a lot of room for improvement. [86,87] The formation of CO was further investigated on Au and Ni coated Cu, [88] SnO2 coated carbon, [89] and Bi-based zeolite coated Ni [90] hollow fibers.…”

Electrochemical CO2 conversion with a flow-through copper hollow fibre: A process parameter evaluation

“…In the years following the report of Kas et al, more investigations involving the hollow fibre configuration for electrochemical CO2 conversion have been presented. [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33] These investigations involve adaptation of the preparation method, [19] modification of the copper hollow fibres by mixing copper and tin in the spinning mixture, [29] or functionalization of the copper hollow fibres with tin, [25,30] gold [23] and nickel. [23] More information about the performance of these fibres is given in Table A.…”

“…Other materials are also used to prepare fibres for electrochemical CO2 conversion. Examples are tin(oxide) incorporated carbon nanotubes (Sn-CNT [20] and SnO2-CNT [18] ), nickel, [31] silver, [21][22]26] and titanium (see Table A.2). [32,34] The reported silver hollow fibres are very selective for electrochemical CO2 to CO conversion, with a CO partial current density of -1.26 A cm -2 and a CO selectivity of 93%.…”