Bandshape luminescence thermometry during in situ temperature measurements has been reported by preparing three catalytically relevant systems, which show temperature-dependent luminescence. One of these systems was further investigated as a showcase for application. Microcrystalline NaYF4 doped with Er3+ and Yb3+ was mixed with a commercial zeolite H-ZSM-5 to investigate the Methanol-to-Hydrocarbons (MTH) reaction, while monitoring the reaction products with online gas chromatography. Due to the exothermic nature of the MTH reaction, a front of increased temperature migrating down the fixed reactor bed was visualized, showing the potential for various applications of luminescence thermometry for in situ measurements in catalytic systems.

CO 2 hydrogenation was carried out over Pt-containing UiO-67 Zr-MOFs at T = 220−280 °C and ambient pressure, with H 2 / CO 2 = 0.2−9 and contact times, τ = 0.004−0.01 g cat •min•mL −1 . The catalysts were characterized by XRD, N 2 adsorption, FESEM, TEM and HRTEM, Pt L 3 -edge XANES and EXAFS, dissolution-NMR, CO chemisorption, IR spectroscopy, and TGA. A positive correlation was observed between the degree of Pt reduction and CO 2 conversion. Contact time variation experiments showed that CO is a primary product of reaction, while CH 4 is a secondary product. Testing of catalyst crystals with 0.15 and 2.0 μm crystal size, respectively, revealed no influence of diffusion on the reaction rate. Comparison to a conventional Pt/SiO 2 catalyst showed very similar activation energy, with E app = 50 ± 3 kJ• mol −1 . However, the turnover frequency over Pt/SiO 2 was significantly lower, and Pt/SiO 2 did not yield methane as a product. The Pt-containing UiO-67 Zr-MOF catalyst showed stable activity during 60 h of testing.

In this work we present 3 showcases that luminescence thermometry is a promising and versatile technique for temperature monitoring in various microfluidic devices.