No abstract

In recent years, atomically precise metal nanoclusters (NCs) demonstrate fascinating vitality in solar energy conversion due to unique atomic stacking fashion, quantum size effect and abundant active sites. Nevertheless, ultra-short...

Crafting spatially controllable charge transfer channels at the nanoscale level remains an enduring challenge in solar-to-chemical conversion technology. Despite the advancements, it still suffers from sluggish interfacial charge transport kinetics and scarcity of strategies to finely modulate charge transport pathways. Herein, this article demonstrates the unexpected charge modulation property of non-conjugated insulating polymer assisted by a universal layer-by-layer self-assembly tactic. Oppositely charged poly(dimethyl diallyl ammonium chloride) (PDDA) and Ti 3 C 2 MXene quantum dots (MQDs) are periodically attached to the wide bandgap metal oxides (WMOs) to design multilayered heterostructured photoanodes. The intermediate PDDA layer acts as an efficacious charge relay medium to access directional electron flow from WMOs to Ti 3 C 2 MQDs, while Ti 3 C 2 MQDs serve as the electron extractor. Charge transfer cascade is thus stimulated on account of the simultaneous electron-trapping capabilities of interim PDDA layer and Ti 3 C 2 MQDs, which synergistically favors the conspicuously boosted charge separation over WMOs, affording the WMOs/(PDDA/MQDs) n photoanodes with considerably enhanced photoelectrochemical (PEC) water oxidation performances. Moreover, PEC performances of such photoanodes can be tuned by interface configuration via assembly number and sequence. This work will provide an insightful perspective to craft a directional charge transfer pathway through insulating polymer for solar energy conversion.

With accelerating consumption of nonrenewable energy resource, mankind is currently facing the dilemma of energy crisis and global warming caused by excessive greenhouse gas emissions. Photoelectrocatalytic (PEC) technique to convert the main greenhouse gas CO2 into hydrocarbon fuels can solve these two issues with one stone. Herein, we summarize the latest developments of semiconductor-based PEC CO2 reduction for solar fuels production in a more comprehensive manner. Our endeavors start with elucidation of the fundamental principles of CO2 reduction technology and influencing factors of PEC CO2 reduction technique, followed by specific introduction on four quintessentially designed PEC CO2 reduction systems, and then multifarious photoelectrodes utilized for these photosystems are systematically introduced. Modification rationales for crafting photoelectrodes with high conversion efficiency and good stability are elucidated. Besides, strategies developed for fine-tuning of selectivity of PEC CO2 reduction products are also discussed. Finally, future outlooks and challenges in this booming research field are reviewed. It is anticipated that our Review would provide enriched and guided information on rational construction of high-performance photoelectrodes for solar-to-chemical fuels conversion.

No abstract