三重态-三重态湮灭上转换（TTA-UC）具有所需激发光强度低(太阳光即可)和工作波长可调等优点，有望在太阳能电池、光催化等领域提高太阳光的利用效率，而上转换过程的Dexter能量传递机制要求各组分运动至彼此碰撞半径之内才能能量传递，导致目前绝大多数TTA上转换发光只能在除氧有机溶剂中实现。实现固体介质中的高效上转换有两个问题亟需解决：1.寻找突破分子运动能力限制的方法；2.解决光敏剂与受体在固相材料中各自堆积而分离的问题。申请人已证明主客体包结与超分子聚集可提高上转换发光效率。在此基础上，该项目拟构建光敏剂与受体的自组装体来解决上述问题。光敏剂与受体的有序组装可防止光敏剂与受体各自堆积；可拉近光敏剂与受体之间的空间距离以提高能量传递效率；同时三重态能量在有序聚集中的能量迁移，可使光敏剂或受体无需通过扩散便能实现能量传递，可望实现聚合物膜和凝胶中的高效上转换，为TTA上转换的实用化奠定基础。

TTA upconversion has several advantages over other upconversion methods, such as allowing for the use of low excitation power density, readily tunable excitation/emission wavelength and high upconversion quantum yield. Both TTET and TTA processes in TTA upconversion follow the Dexter energy transfer mechanism. The components involved have to diffuse in the media and collide within the lifetime of their excited states to complete the energy transfer. It is easily realized when the components were dissolved in low-viscosity solvents, while for upconversion in polymers or in viscous liquid mixtures, the slow diffusion of dye molecules in these matrices inevitably lowers the TTET and TTA efficiencies, thus, the molecular mobility become the main restrictions for the enhancing of TTA-UC efficiency in solid phase. The insufficient TTA-UC emission and strict deaeration process for avoiding oxygen quenching of triplet state in solvent make them far from real-world applications. Herein, in order to address these fundamental problems of TTA upconversion, based on our previous work, a general motif in which the sensitizer and the acceptor are spontaneously co-assembled together by supramolecular interactions such as host-guest binding, hydrophobic interaction and hydrogen bonding was proposed. The formation of photosensitizer and acceptor co-assemblies can prevent them from accumulation in the polymers, and the sensitizer and annihilator are positioned in close proximity to each other, which is expected to improve the TTET and TTA processes. Most importantly, energy-migration-based TTA-UC instead of the conventional molecular diffusion-based mechanism can be achieved in the supramolecular co-assemblies, therefore, efficient in-air upconversion emission could be achieved in gels and solid films, which will lay a solid foundation for the applications of TTA-UC.