Enriching Photoelectrons via Three Transition Channels in Amino-Conjugated Carbon Quantum Dots to Boost Photocatalytic Hydrogen Generation

Well-steered transport of photogenerated carriers in optoelectronic systems underlies many emerging solar conversion technologies, yet assessing the charge transition route in nanomaterials remains a challenge. Herein, we combine the photoinduced absorption, emission, and excitation properties in high luminescent carbon quantum dots (CQDs) with an amino-modified surface to identify the existence of three photoelectron transition channels, that is, near-band-edge transition, multiphoton active transition in CQDs, and transfer from amino groups to CQDs, and together they contribute to strong blue photoluminescence (PL) independent of the excitation wavelength. Moreover, the enriching electron reservoir via these three channels was demonstrated in a holes cleaning environment to efficiently trigger water splitting into hydrogen with excellent stability and recyclability.