Few-layered black phosphorus/cucurbit[6]uril as a Pd catalyst support for photo-assisted electrocatalytic ethanol oxidation reaction

In this work, macrocyclic molecule cucurbit[6]uril (CB[6])-modified two-dimensional black phosphorus nanosheets (BPNSs) used as photoactivated support were synthesized by a simple solvothermal method . Palladium nanoparticles were anchored on the surface of BP-CB[6] to obtain the composite material Pd/BP-CB[6] by using a chemical reduction method. Then, the electrocatalytic activity of the composite material modified electrode in the ethanol oxidation reaction (EOR) was investigated. The Pd/BP-CB[6] catalyst exhibits a high mass activity (1420 mA·mg Pd −1 ), which is 4.1 times higher than commercial Pd/C. Impressively, the ethanol oxidation activity of the Pd/BP-CB[6] electrode under visible light irradiation (1900 mA·mg Pd −1 ) is 1.34 times higher than under dark conditions. The result is obtained through a series of evaluations, including cyclic voltammetry , chronopotentiometry , chronoamperometry , and electrochemical impedance spectroscopy , in which the prepared Pd/BP-CB[6] shows higher catalytic activity and stability than Pd/BP. These results suggest that the synergistic effect of photocatalysis and electrocatalysis improves the electron transport kinetics of the Pd/BP-CB[6] electrode in the EOR process. Two-dimensional black phosphorus nanosheets can be used as promising photoactivated supports, to which functional material CB[6] is fixed by hydrogen bonding . Meanwhile, the electrostatic interaction between CB[6] and noble metal helps to improve the stability of the catalyst. This work provides a new idea for developing efficient photoresponsive electrode material in direct ethanol fuel cells.