Fabrication of Light-Harvesting Au Nanoclusters System via Sequential Energy Transfer and the Usage as “On/Off” Switchable Logic Gates

Light-harvesting is an indispensable process in photosynthesis, and researchers have been exploring various structural scaffolds to create artificial light-harvesting systems. Herein, a light-harvesting system (LHS) is constructed by AuNCs. First, ionic liquid 1-Dodecyl-3-methylammonium bromide (C 12 mimBr) and Ba 2+ are used to co-assembly with 6-aza-2-thiothymine (ATT) modified AuNCs to get ATT-AuNCs/C 12 mimBr/Ba 2+ (M-AuNCs) with network superstructures and improved emission efficiency. This makes M-AuNCs applicable for aqueous LHS. Furthermore, the green-emitting network serves as energy donors, and red-emitting positive dyes (rhodamine B) act as acceptors. An efficient energy transfer process occurs between them with an energy transfer efficiency of 94.1%. Significantly, sequential energy transfer can also be realized with the further addition of deep-red emitting dye (sulforhodamine 101). Notably, the system can only be constructed by M-AuNCs instead of mono-dispersed ATT-AuNCs. Based on this, a FRET-triggered logic gate is established, in which C 12 mimBr and Ba 2+ can be considered as energy switches to turn on/off the logic gate. Therefore, this work not only fabricates an AuNCs-based LHS through sequential energy transfer, but also develops a FRET-triggered logic gate, which has potential application in molecular recognition and information encryption.