In-situ assembly of Cu/CuxO composite with CNT/Bacterial cellulose matrix as a support for efficient CO2 electroreduction reaction to CO and C2H4.

[Display omitted] • Supported by a conductive and larger specific area CNT/BC 3D nanocomposite film. • Copper-based electrode synthesized via in situ chemical reduction in solution. • Synergistic effect of CNT and Cu favors the transmission of charge. • NaBH 4 is more favorable to the stability of ECR-CO 2 as reducing agent. A CNT/Bacterial Cellulose (BC) nanocomposite with a large surface area and conductive properties was in-situ cultivated to retain the native 3D nanofibril network. The Cu-Cu x O/CNT/BC nanocomposite electrode was in-situ fabricated via reduction with the CNT/BC composite as a support, comparing KBH 4 and NaBH 4 as a reducing agent to obtain efficient electrodes for CO 2 reduction (ECR-CO 2). Both electrodes exhibited higher performance than the traditional carbon cloth or pristine BC supported Cu-based catalysts for conversion of ECR-CO 2 to CO and C 2 H 4. The CNT/BC as a support provided not only more active sites for copper catalyst but also increased the charge transfer and selective performance of C 2 H 4 product, due to the synergistic effect of CNT and copper. The smaller honeycomb and dendritic lamellar crystal morphology of the obtained Cu-Cu x O/CNT/BC NaBH4 electrode possessed a large electrochemical specific surface area, providing more active sites for ECR-CO 2. The double-layer capacitance and the current density reached 11.8 mF cm−2 and 33.3 mA cm−2, respectively. At a potential of −1.5 V RHE , the Faraday efficiency (FE CO + FE C2H4) was 66%. Moreover, the Cu-Cu x O/CNT/BC nanocomposite electrode was very stable, and withstood tolerance in ECR-CO 2 for more than 20 h. This study possibly will provide a new design for catalyst support on CNT/BC substrate to regulate advanced catalysts/electrodes for different applications, especially to ECR-CO 2 in terms of higher charge transport properties, lower contact resistance, higher current density, and more stable CO 2 electroreduction performance. [ABSTRACT FROM AUTHOR]