Functional Materials with Wide‐Spectral‐Responsive Photocatalytic Activity and Real‐Time Temperature Feedback: The Electrospun Fibers Embedded with NaGdF4‐Tm‐Yb@TiO2 Nanocrystals

Abstract

AbstractIn this work, combining the advantages of upconversion materials, nanofibers, and TiO2 semiconductors, the composite fibers embedded with NaGdF4: Tm3+, Yb3+@TiO2 nanocrystals (NGF‐TY@TiO2 NCs) are prepared as wide‐spectral (UV‐NIR) response photocatalysts and temperature sensing materials. Based on the FIR technique, both the thermally (3F2,3 and 3H4) and nonthermally (1G4 and 3F2,3) coupled levels of Tm3+ are confirmed to be applicable as temperature probes for real‐time monitoring and feedback of the working temperature of the catalytic degradation process, and the maximum relative sensitivity values of SR1 and SR2 are as high as 2.760%K−1 and 3.019%K−1 at 304 K, respectively. Under 977 nm laser excitation, the energy migration from NGF‐T0.4Y6 to TiO2 is demonstrated to a fluorescence resonance energy transfer process. The degradation ratio of rhodamine B (RhB) is 19.3% in the presence of NGF‐T0.4Y6@TiO2/PAN fibers and the degradation constant K reaches 0.00117 min−1 after 3 h irradiating from Xe lamp with a UV cutoff filter. Accordingly, this study suggests a new perspective to utilize the NIR energy of sunlight for photocatalytic application based on TiO2, and the addition of dual temperature feedback provides a reliable reference for the development of safer and more efficient catalytic materials.