Layer-Stacked Zn with Abundant Corners for Selective CO₂ Electroreduction to CO

Abstract

Electric-driven CO2 reduction offers a promising strategy for CO2 conversion into valuable chemicals and fuels. However, developing low cost and efficient catalysts is still a challenge. Although earth-abundant Zn with the capability of converting CO2 to CO is considered to be one of the promising materials, the low selectivity and stability of Zn catalyst limit its practical applications in CO2 reduction. Herein, we report a highly selective and stable layer-stacked Zn catalyst prepared by an efficient and facile electrochemical method for CO2 reduction to CO. The layer-stacked Zn can produce CO with more than 90% Faradaic efficiency at an overpotential of 0.9 V. Notably, the layer-stacked Zn maintained ∼90% CO selectivity in CO2 electrolysis for more than 70 h, which significantly surpasses the durability of the reported Zn-based catalysts to date. In addition, after prolonged CO2 reduction, the robust catalytic performance of layer-stacked Zn can be recovered repeatedly by the simple electrochemical method, which may be linked to the maintained layer-stacked structure even after multiple reactivations. Further analysis suggests that while abundant low-coordinated sites (corners and edges) can be created on layer-stacked Zn, the enhanced catalytic performance in CO2 reduction is mainly correlated with the created corners instead of edges, owing to that corners not only improve the intrinsic CO2 reduction activity but also inhibit H2 evolution simultaneously.

Progress and Perspectives of Pulse Electrolysis for Stable Electrochemical Carbon Dioxide Reduction

“…They attributed this observation to the effect of catalyst layer etching, which has previously been observed in aqueous GDE systems. Recently, Zhou et al 124 reported a layer-stacked Zn catalyst with abundant corners that are selective for CO production. By periodically reactivating the catalyst with several anodic oxidation and reduction cycles, the author extended the catalyst lifetime to about 40 h. These promising results highlight the potential of this strategy to enhance the stability of CO 2 conversion systems by some anodic periodic pulsing conditions.…”

Determination of local pH in CO2 electroreduction

“…[1][2][3][4][5][6][7][8][9][10] In this process, the anthropogenic carbon cycle can be closed by coupling with renewable electricity. In the past few decades, most of the CO 2 reduction studies have been focused on developing efficient and stable electrocatalysts for selectively converting CO 2 into a desired product through engineering the catalysts such as modulation of crystal facets, 11-13 compositions [14][15][16][17][18][19][20] and morphology 7,[21][22][23] of the catalyst surface. The notable advancements in the enhancement for selectivity and activity of CO 2 electrolysis have been made by engineering the catalysts.…”

Constructing Highly Efficient ZnO Nanocatalysts with Exposed Extraordinary (110) Facet for CO2 Electroreduction

“…Notably, Zn-based catalysts have attracted much attention for CO 2 conversion due to their low cost, abundant reserves, and accessible CO selectivity, − which are considered as a promising alternative to noble metal catalysts. It was reported that ZnO nanosheets fabricated by adjusting alkaline additives and the molar ratios of zinc source/urea showed good CO 2 RR performance .…”