Open AccessPanchromatic Ternary Polymer Dots Involving Sub-Picosecond Energy and Charge Transfer for Efficient and Stable Photocatalytic Hydrogen Evolution
Author(s) -
Aijie Liu,
Lars Gedda,
Martin Axelsson,
Mariia V. Pavliuk,
Katarina Edwards,
Leif Hammarström,
Haining Tian
Publication year - 2021
Publication title -
journal of the american chemical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 7.115
H-Index - 612
eISSN - 1520-5126
pISSN - 0002-7863
DOI - 10.1021/jacs.0c12654
Subject(s) - chemistry , ternary operation , photochemistry , photocatalysis , ultrafast laser spectroscopy , acceptor , quantum dot , optoelectronics , materials science , organic chemistry , optics , catalysis , laser , physics , computer science , programming language , condensed matter physics
Panchromatic ternary polymer dots (Pdots) consisting of two conjugated polymers (PFBT and PFODTBT) based on fluorene and benzothiadiazole groups, and one small molecular acceptor (ITIC) have been prepared and assessed for photocatalytic hydrogen production with the assistance of a Pt cocatalyst. Femtosecond transient absorption spectroscopic studies of the ternary Pdots have revealed both energy and charge transfer processes that occur on the time scale of sub-picosecond between the different components. They result in photogenerated electrons being located mainly at ITIC, which acts as both electron and energy acceptor. Results from cryo-transmission electron microscopy suggest that ITIC forms crystalline phases in the ternary Pdots, facilitating electron transfer from ITIC to the Pt cocatalyst and promoting the final photocatalytic reaction yield. Enhanced light absorption, efficient charge separation, and the ideal morphology of the ternary Pdots have rendered an external quantum efficiency up to 7% at 600 nm. Moreover, the system has shown a high stability over 120 h without obvious degradation of the photocatalysts.