Europium/1,3,5-Benzenetricarboxylic Acid Metal-Organic Framework Nanorods Decorated with CdSe Quantum Dots as Coatings for Noncontact Ratiometric Optical Temperature Sensing

The development of temperature sensing platforms based on the dual-emission optical response principle has received much attention for their remarkable potential, while the design of sensitive and reliable thermometers remains an unresolved challenge. Herein, we successfully fabricated a dual-emission temperature probe by attaching CdSe quantum dots to europium/1,3,5-benzenetricarboxylic acid (Eu-BTC) metal-organic framework nanorods, followed by deposition on a POSS-based polymer film, which afforded the construction of a temperature-responsive specialized coating that yielded outstanding temperature responses, high sensitivity, adhesion, and hydrophobicity. The time-dependent effect of the dimensions and quantum dot distribution in the CdSe/Eu-BTC materials was then investigated by reaction time modulation to obtain the best morphology (quantum dot dimension of 3.3 ± 0.8 nm). Due to the contrasting thermally responsive photoluminescent behaviors of CdSe quantum dots and Eu-BTC, temperature-dependent measurements revealed that the specialized coating exhibited significant exponential temperature sensing performances (R² = 0.99772) and high relative sensitivity (3.02%°C^-1). Moreover, the specialized coating displayed superior adhesive properties (1.385 MPa on the surface of steel) and hydrophobicity (103°) due to the addition of POSS-based copolymers. This work presents a feasible strategy for designing high-performance solid-state nanoluminescent temperature probes, offering great promise for the development of ratiometric temperature sensing systems with high sensitivity.