CO2-Induced Fibrous Zn Catalyst Promotes Electrochemical Reduction of CO2 to CO

Mengquan Guo,Lihong Zhang,Linfa Li,Jixiao Li,Yuxin Huang,Xiangxiang Li,Yanhong Xu,Yiren Lu

doi:10.3390/catal11040477

Mengquan Guo, Lihong Zhang + Show 6 more

Open Access

https://doi.org/10.3390/catal11040477

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Abstract

The electrochemical reduction of CO2 is a promising strategy to achieve efficient conversion and utilization. In this paper, a series of Zn catalysts were prepared by electrodeposition in different atmospheric conditions (N2, CO2, H2, CO). A fibrous Zn catalyst (Zn-CO2) exhibits high electrochemical activity and stability. The Zn-CO2 catalyst shows 73.0% faradaic efficiency of CO at −1.2 V vs. RHE and the selectivity of CO almost did not change over 6 h in −1.2 V vs. RHE. The excellent selectivity and stability is attributed to the novel fibrous morphology, which increases the electrochemical active surface area. X-ray diffraction (XRD) results show that Zn-CO2 catalyst has a higher proportion of Zn (101) crystal planes, which is considered to be conducive to the production of CO. The search further demonstrates the importance of morphology control for the preparation of highly active and stable catalysts.

Highlights

Over the past few years, heavy consumption of fossil fuels has increased the concentration of carbon dioxide (CO2 ) in the atmosphere, leading to many environmental problems such as greenhouse effect and energy dilemma [1]
The electrochemical performance of the prepared electrodes for CO2 reduction reaction (CO2 RR) was evaluated by linear sweep voltammetry (LSV) at 5 mV/s in pure KHCO3 electrolyte solution saturated with CO2
The Zn-CO2 catalyst obtained with porous fibers and uniform tiny pores exhibited high activity and selectivity for CO2 RR to CO, with FE of CO (FECO)

Summary

Introduction

Over the past few years, heavy consumption of fossil fuels has increased the concentration of carbon dioxide (CO2 ) in the atmosphere, leading to many environmental problems such as greenhouse effect and energy dilemma [1]. The challenge of electrochemical CO2 RR is the preparation of catalysts with high activity, selectivity and stability, which is the core for catalytic research. The SEM images show that the surface of Zn-CO2 catalyst is covered by porous fibers with uniform tiny pores, which increases the electrochemical active surface area (ECSA). This is the main reason for the excellent catalytic performance of Zn-CO2 catalysts. The research prepared a Zn catalyst with new morphology and excellent activity and stability of electrochemical CO2 RR, which develops a new means and idea for the preparation of more efficient and stable Zn catalysts. This work is of great value and significance in solving the challenge of low activity and poor stability in electrochemical CO2 RR

Electrochemical Performance

Characterization of Catalysts

Fabrication of Zn Catalysts

Eelectrocatalytic Test for CO2 RR

Catalyst Characterization

Conclusions