In Situ Local Temperature Mapping in Microscopy Nano‐Reactors with Luminescence Thermometry

Abstract

In situ and operando experiments play a crucial role in understanding the mechanisms behind catalytic processes. In these experiments it is important to have precise control over pressure and temperature. In this work, we use luminescence thermometry to map the temperature distribution in a 300 μm microelectromechanical system nano‐reactor with a resolution of ca. 10 μm. These measurements showed a temperature gradient between the center and edge of the heater of ca. 200 °C (at Tset=600 °C) in vacuum and, in addition, a large offset of the local temperature of ca. 100 °C (at Tset=600 °C) in a non‐vacuum (i. e., air, He and H2) environment. The observed temperature heterogeneities can explain differences observed in the reduction behavior of Co‐based Fischer‐Tropsch synthesis catalyst particles at different locations in the nano‐reactor as determined by scanning transmission X‐ray microscopy.

Making Nd3+ a Sensitive Luminescent Thermometer for Physiological Temperatures—An Account of Pitfalls in Boltzmann Thermometry

“…Temperature is an important control parameter that governs, e.g., the rate of chemical reactions, but also the optimum working efficiency of electronic devices or dynamics and viability of biological systems. As such, non-invasive, sensitive and remote temperature measurement techniques with the capability to spatially resolve temperature variations down to the micrometer range are becoming increasingly relevant [1][2][3][4][5][6][7]. Physiological temperature sensing is especially demanding in that regard as it even requires to accurately distinguish temperature fluctuations below 1 K. Luminescence nanothermometry is an appealing and rapidly emerging technique that meets those requirements and constantly improves [8][9][10][11][12][13][14].…”

In‐situ Transmission Electron Microscope Techniques for Heterogeneous Catalysis

“…Recently, Pérez et al. reported a newly‐designed micro‐heating system with ultra temporal‐stability, which kept the heating sample at constant z‐position (no bulging) up to 700 °C and allowed EDX acquisition in the TEM up to 1000 °C …”

“…[48][49][50] Recently, Pérez et al reported a newly-designed micro-heating system with ultra temporal-stability, which kept the heating sample at constant z-position (no bulging) up to 700°C and allowed EDX acquisition in the TEM up to 1000°C. [16,51] With the help of precision machining technology and MEMS technology, a special holder equipped with a nanoreactor can be manufactured for in-situ TEM study, which allows gases to be introduced and sealed within the reactor (illustrated in Figure 2c). The nanoreactor was assembled by two (top and bottom) chips with transparent SiN x membranes as windows.…”

Luminescent Ratiometric Thermometers Based on a 4f–3d Grafted Covalent Organic Framework to Locally Measure Temperature Gradients During Catalytic Reactions

“…Already various optical methods, such as Raman scattering, thermography, thermal reflection and luminescence have been investigated for use in new types of thermometers [8] . Among these techniques, luminescence‐based thermometry is proving to be a very promising alternative for measuring temperature and has shown excellent results in the first studies on in situ luminescence thermometry during catalytic reactions reported by Meijerink and Weckhuysen [1, 2, 9–12] . Band shape luminescence thermometry is a ratiometric spectroscopic technique, which can be employed to accurately monitor temperature non‐invasively [3] .…”