Fabrication of CuNCs/LDHs Films with Excellent Luminescent Properties and Exploration of Thermosensitivity

Fluorescent copper nanoclusters (CuNCs) have been drawing great research interest because of their fascinating physicochemical properties. However, the low quantum yield (QY) and poor stability of CuNCs have limited their applications. In this work, CuNCs were anchored onto the layered double hydroxides (LDHs) by the layer-by-layer (LBL) assembly method, and the obtained CuNCs/LDHs ultrathin films displayed an ordered periodic long-range structure and uniform morphology. The CuNCs/LDHs films indicate the strong orange-red emission with higher QY (16.66%) and prolonged fluorescence lifetime (9.05 μs), which is obviously better than that of individual CuNCs. The experimental studies and theoretical calculations both reveal that the location and confinement effects derived from LDHs nanosheets enhance the QY of CuNCs. In addition, the CuNCs/LDHs films are temperature-responsive in photoluminescence (PL) and electrogenerated chemiluminescence (ECL). Consequently, it provides a new and facile approach to fabricate CuNCs-based films accompanied by excellent luminescent properties, which indicate the great potential for temperature sensing applications.