School of Civil and Environmental Engineering, Georgia Institute of Technology, 200 Bobby Dodd Way, Atlanta, Georgia 30332, USA.
J Am Chem Soc. 2012 Oct 24;134(42):17478-81. doi: 10.1021/ja308789u. Epub 2012 Oct 16.
We herein report the first instance of aqueous-phase photosensitization of semiconductor photocatalysts (WO(3) loaded with Pt) through triplet-triplet annihilation (TTA)-based upconversion of sub-band-gap photons. The TTA-based upconversion (UC) was achieved in the aqueous phase by encapsulating the solvent phase containing a benchmark platinum(II) octaethylporphyrin/9,10-diphenylanthracene sensitizer/acceptor pair in a rigid polymer shell in the form of aqueous dispersible microcapsules. A mixture of hexadecane and polyisobutylene was used as the inner solvent phase. This eliminated the need for the deoxygenation step that is essential for existing TTA-based UC processes and enabled stable UC to occur even after a month of exposure to the ambient environment. The photoluminescence properties were examined, and UC-assisted photochemical production of hydroxyl radical from green (532 nm) light irradiation was demonstrated for the first time.
我们在此报告了首例通过亚带隙光的三重态-三重态湮灭（TTA）上转换实现半导体光催化剂（负载 Pt 的 WO(3)）水相光致敏化。TTA 基上转换（UC）是通过将含有基准铂（II）八乙基卟啉/9,10-二苯基蒽敏化剂/受体对的溶剂相封装在刚性聚合物壳中以水可分散微胶囊的形式在水相中实现的。十六烷和聚异丁烯的混合物被用作内溶剂相。这消除了对于现有 TTA 基 UC 过程至关重要的脱氧步骤，并使 UC 即使在暴露于环境一个月后仍能稳定发生。我们检查了光致发光性质，并首次证明了绿光（532nm）辐照下 UC 辅助的光化学产生羟基自由基。
