Self-Assembled Perylenediimide Nanoaggregates with an Alternate Stringlike Morphology as Photoanodes to Enhance the H2O2 Photoelectrochemical Cell Performance

A self-assembled supramolecular photocatalyst of benzoic acid-substituted perylenediimide (SA-BAPDI) is successfully prepared, forming an alternate stringlike morphology driven by intermolecular hydrogen-bonding and π-π interactions. This unusual morphology induces a strong built-in electric field and an enormous π-conjugated effect, which can promote efficient separation of photogenerated carriers. Meanwhile, SA-BAPDI photocatalyst applied as the photoanode in the H2O2 photoelectrochemical cell for the first time can facilitate photocatalytic H2O2 production by water oxidation, which can be used as fuel to generate electricity through redox reactions and further to achieve solar-chemical-electrical energy conversion. The SA-BAPDI-based cell displays the maximum light power density of 1.06 mW·cm-2 and the specific capacitance of 5025 mF·cm-2 after 0.5 h of irradiation, which can still retain the original value of 50% in the dark for 12 h of continuous operation. This study verifies that morphology regulation of self-assembled perylenediimide supramolecular photocatalytic materials benefits the design and development of a high-performance H2O2 photoelectrochemical cell.