Polymer‐Mediated Electron Tunneling Towards Solar Water Oxidation

• Published in: Advanced functional materials Vol. 32; no. 7
• Main Authors: Wei, Zhi‐Quan, Hou, Shuo, Zhu, Shi‐Cheng, Xiao, Yang, Wu, Gao, Xiao, Fang‐Xing
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 01.02.2022
• Subjects: Charge transfer; Electron tunneling; electron‐tunneling photosystems; Energy harvesting; Heterostructures; layer‐by‐layer assemblies; Materials science; Metal oxides; metal‐oxide; Modulation; Oxidation; photoelectrochemical water oxidation; Polymers; Quantum dots; Solar energy conversion; Substrates; transition metal chalcogenides quantum dots; Transition metal compounds
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202106338

Exploiting emerging artificial photosystems with regulated vectorial charge transfer pathways is retarded by the difficulties in precise interface modulation at the nanoscale level, deficiency of suitable assembly methodologies, and ultra‐short charge lifetime. Herein, it is first conceptually demonstrated the general design of transition metal chalcogenides quantum dots (TMCs QDs)‐insulating polymer‐metal oxides (MOs) electron‐tunneling photosystems, wherein TMCs QDs are controllably layer‐by‐layer self‐assembled on the MOs substrates assisted by an ultrathin insulating polymer interim layer. It is ascertained that electrons photoexcited over TMCs QDs in spatially highly ordered MOs/(TMCs QDs/polymer)n multilayered heterostructures can be unidirectionally extracted and tunneled to the MOs substrates across the intermediate insulating polymer layer by engendering the tandem charge transfer to accelerate the interfacial charge migration kinetics, thereby triggering the significantly boosted net efficiency of solar‐driven photoelectrochemical water oxidation. This study would spark new inspirations for designing novel electron‐tunneling photosystems for fine carrier modulation towards solar energy harvesting and conversion. In these conceptually novel MOs/(TMCs QDs/PSS)n multilayered photosystems, periodically intercalated insulating PSS layer enables the unexpected electron tunneling over TMC QDs‐PSS‐MOs photoanodes with electrons photoexcited from TMCs QDs directionally flowing to the MOs matrixes across the intermediate insulating PSS layer, contributing to the tandem charge transport and leading to significantly enhanced net efficiency of photoelectrochemical water oxidation performances.