Bimetallic AuCu Alloy Decorated Covalent Organic Frameworks for Efficient Photocatalytic Hydrogen Production

Covalent organic frameworks (COFs) represent a kind of novel crystalline porous organic substances with extended π -conjugation framework and tunable structures, which display great promise in photocatalysis. However, unadorned COFs suffer from sluggish reaction kinetics, and a cocatalyst is essentially needed to reduce the activation barrier toward specific surface reaction and accelerate reaction kinetics. In this work, bimetallic alloys serving as co-catalysts were decorated on COFs to enhance the photocatalytic hydrogen evolution performance. By precisely-tuning the ratio of AuCu alloy, the resultant Au 1 Cu 5 /COF-TpPa displays the highest photocatalytic hydrogen generation rate (8.24 mmol∙g −1 ∙h −1 ), even surpassing the Pt modified COF-TpPa (6.51 mmol∙h −1 ∙g −1 ). According to the systematic characterizations and theoretical calculation, Au 1 Cu 5 /COF-TpPa exhibits the significantly enhanced charge carrier separation efficiency and reduced H* formation energy barrier, thus possessing high photocatalytic performance. This work affords a valuable approach to advancing COF-based photocatalysts by employing bimetallic alloy cocatalysts. Download: Download high-res image (117KB) Download: Download full-size image