posted on 2018-02-13, 17:53authored byJi-fei Feng, Shui-ying Gao, Jianlin Shi, Tian-fu Liu, Rong Cao
Temperature
plays a crucial role in both scientific research and industry. However,
traditional temperature sensors, such as liquid-filled thermometers,
thermocouples, and transistors, require contact to obtain heat equilibrium
between the probe and the samples during the measurement. In addition,
traditional temperature sensors have limitations when being used to
detect the temperature change of fast-moving samples at smaller scales.
Herein, the carbon quantum dots (C-QDs) functionalized metal–organic
framework (MOF) composite film, a novel contactless solid optical
thermometer, has been prepared via electrophoretic deposition (EPD).
Instead of terephthalic acid (H2BDC), 1′,2′,4′,5′-benzenetetracarboxylic
(H4BTEC) acid was employed to construct a UiO-66 framework
to present two uncoordinated carboxylic groups decorated on the pore
surface. The uncoordinated carboxylic groups can generate negative
charges, which facilitates the deposition of film on the positive
electrode during the EPD process. Moreover, UiO-66-(COOH)2 MOFs can absorb C-QDs from the solution and prevent C-QDs from aggregating,
and the well-dispersed C-QDs impart fluorescence characteristics to
composites. As-synthesized composite film was successfully used to
detect temperature change in the range of 97–297 K with a relative
sensitivity up to 1.3% K–1 at 297 K.