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Chip-Based MEMS Platform for Thermogravimetric/Differential Thermal Analysis (TG/DTA) Joint Characterization of Materials. | LitMetric

AI Article Synopsis

  • The study presents a MEMS chip-based microsystem that combines thermogravimetric analysis (TG) and differential thermal analysis (DTA) for comprehensive thermal characterization of materials, allowing for analysis of mass and temperature changes during reactions or phase transitions.
  • This microinstrument requires only nanogram to microgram quantities of samples, making it suitable for analyzing energetic materials like strong oxidants, which was challenging for traditional TG/DTA instruments that need larger sample sizes.
  • With superior features including higher sensitivity, faster heating rates, smaller size, and lower power consumption, the fabricated MEMS microsystem offers significant advancements over existing commercial thermal analysis instruments.

Article Abstract

Combined use of thermal analysis techniques can realize complementarity of different characterization methods. Comprehensive thermal analysis with both thermogravimetric analysis and differential thermal analysis (TG/DTA) can measure not only mass change of a sample but also its temperature change during programmed heating-induced reaction or phase transition processes, thereby obtaining multiaspect thermal information of the material such as dehydration, structural decomposition, phase change and thermal stability. This study proposes and develops a MEMS chip-based TG/DTA microsystem that integrates both programmed heating and detecting elements into a TG chip and a DTA chip to enable the microinstrument performing TG/DTA joint characterization under microscope observation. The TG chip contains a self-heating resonant microcantilever to measure heating-induced mass change of a sample and the DTA chip is with a microheater and a temperature-detecting thermopile integrated on a suspended thermal-insulating diaphragm. Only nanogram and microgram-level samples are needed for the TG and DTA chips, thereby achieving safe measurement to energetic materials such as strong oxidants. The chip-based microinstrument surpasses the state-of-the-art commercial TG/DTA instruments that have, in the long term, suffered from large sample-amount (milligram level) requirements and have been unable to measure energetic materials. Compared with commercial instruments, the chip-based microinstrument is advantageous given its more accurate analysis, much higher heating rate, much smaller instrument volume and much lower power consumption, etc. The microinstrument has been fabricated by using wafer-level MEMS techniques. Testing results show that the mass-detection sensitivity of the TG-chip is as high as 0.45 Hz/pg in air and the temperature sensitivity of the DTA chip achieves 2.9 mV/K under the high heating rate of 25 °C/s. The strong oxidant of KMnO is analyzed with the TG/DTA joint characterization under microscopic observation. At the same time as microscope observation of the thermal decomposition phenomena, two-step thermal decomposition process of KMnO is identified and the thermal decomposition temperatures are obtained. The TG/DTA microinstrument is promising to be applied for study of various materials.

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Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8950653PMC
http://dx.doi.org/10.3390/mi13030445DOI Listing

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