School of Chemical and Environmental Engineering, Shanghai Institute of Technology, Shanghai 201418, China.
State Key Lab of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China.
Sensors (Basel). 2023 Jul 4;23(13):6147. doi: 10.3390/s23136147.
We investigate the MEMS resonant cantilevers for high-performance thermogravimetric analysis (TGA) of chemical decomposition, featuring high accuracy and minimized thermal lag. Each resonant cantilever is integrated with a microheater for sample heating near the free end, which is thermally isolated from the resonance excitation and readout elements at the fixed end. Combining finite element modeling and experiments, we demonstrate that the sample loading region can stabilize within ~11.2 milliseconds in response to a step heating of 500 °C, suggesting a very fast thermal response of the MEMS resonant cantilevers of more than 10 °C/s. Benefiting from such a fast thermal response, we perform high-performance TG measurements on basic copper carbonate (Cu(OH)CO) and calcium oxalate monohydrate (CaCO·HO). The measured weight losses better agree with the theoretical values with 5-10 times smaller thermal lags at the same heating rate, compared with those measured by using conventional TGA. The MEMS resonant cantilevers hold promise for highly accurate and efficient TG characterization of materials in various fields.
我们研究了用于高性能热重分析（TGA）的微机电系统（MEMS）谐振悬臂梁，以实现化学分解的高准确性和最小化热滞后。每个谐振悬臂梁都集成了一个微加热器，用于在自由端附近加热样品，该微加热器与固定端的谐振激励和读出元件热隔离。通过有限元建模和实验相结合，我们证明在 500°C 的阶跃加热下，样品加载区域可以在~11.2 毫秒内稳定，表明 MEMS 谐振悬臂梁的热响应非常快，超过 10°C/s。得益于这种快速的热响应，我们对基本碳酸铜（Cu(OH)CO）和一水合草酸钙（CaCO·HO）进行了高性能 TG 测量。与使用传统 TGA 测量相比，在相同的加热速率下，测量得到的重量损失与理论值更吻合，热滞后小 5-10 倍。MEMS 谐振悬臂梁有望在各个领域对材料进行高精度和高效率的 TG 特性分析。
