Enhanced Electrochemical CO2 Reduction of Cu@CuxO Nanoparticles Decorated on 3D Vertical Graphene with Intrinsic sp3‐type Defect. (4th May 2020)

• Record Type: Journal Article
• Authors: Ma, Zhipeng; Tsounis, Constantine; Kumar, Priyank V.; Han, Zhaojun; Wong, Roong Jien; Toe, Cui Ying; Zhou, Shujie; Bedford, Nicholas M.; Thomsen, Lars; Ng, Yun Hau; Amal, Rose
• Is Part Of: Advanced functional materials. Volume 30:Number 24(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-05-04
• Subjects: Ar plasma treatment -- copper nanoparticles -- electrochemical CO2 reduction -- intrinsic carbon defects -- vertical graphene; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.201910118
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: Defective 3D vertical graphene (VG) with a relatively large surface area, high defect density, and increased surface electrons is synthesized via a scalable plasma enhanced chemical vapor deposition method, together with a postsynthesis Ar‐plasma treatment (VG‐Ar). Subsequently, Cu@Cu x O nanoparticles are deposited onto VG‐Ar (Cu/VG‐Ar) through a galvanostatic pulsed electrodeposition method. These Cu@Cu x O nanocatalyst systems exhibit a superior electrochemical CO2 reduction performance when compared to Cu‐based catalysts supported on commercial graphene paper or pristine VG without postsynthesis Ar‐plasma treatment. The Cu/VG‐Ar achieves the highest CO2 reduction Faradaic efficiency of 60.6% (83.5% of which are attributed to liquid products, i.e., formate, ethanol, and n‐propanol) with a 5.6 mA cm −2 partial current density at −1.2 V versus reversible hydrogen electrode (RHE). The improved CO2 reduction performance of Cu/VG‐Ar originates from the well‐dispersed Cu@Cu x O nanoparticles deposited on the defective VG‐Ar. The intrinsic carbon defects on VG‐Ar can suppress the hydrogen evolution reaction as well as tune the interaction between VG and Cu@Cu x O, thus impeding the excessive oxidation of Cu2 O species deposited on VG‐Ar. The defective VG‐Ar and stabilized Cu@Cu x O enhances CO2 adsorption and promotes electron transfer to the adsorbed CO2 and intermediates on the catalyst surface, thus improving the overall CO2 reduction performance. Abstract : Defective 3D vertical graphene (VG‐Ar) with sp 3 ‐type intrinsic carbon defects is synthesized via a plasma enhanced chemical vapor deposition method followed by a postsynthesis Ar‐plasma treatment. The sp 3 ‐type intrinsic carbon defects improve the electrochemical CO2 reduction performance of Cu/VG‐Ar by stabilizing the Cu2 O species, suppressing the hydrogen evolution reaction process, and channeling electrons to the adsorbed CO2 and intermediates.