Critical analysis of micro-thermogravimetry of CuSO4·5H2O crystals using heatable microcantilevers
Critical analysis of micro-thermogravimetry of CuSO4·5H2O crystals using heatable microcantilevers
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DOI：
10.1088/1361-6439/ab30a3
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发表时间：
2019-07
影响因子：
2.3
通讯作者：
N. Tiwary;M. Zakerin;F. Natalio;E. Biegler;Fritzsche Marco;Hermann Kaubitzsch;A. Laha;R. Berger;V. Rao
中科院分区：
文献类型：
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作者：
N. Tiwary;M. Zakerin;F. Natalio;E. Biegler;Fritzsche Marco;Hermann Kaubitzsch;A. Laha;R. Berger;V. Rao
微/纳米热重（TG）采用MEMS具有显着的潜力，以提高最低样品质量和质量分辨率相比，商业TG仪器。虽然已经有一些关于MEMS TG的先前报告，但没有一个详细地分析所获得的TG曲线。在这项工作中，我们设计并制作了一个集成了微加热器和温度传感器的微机电热重装置（MMTG）。该装置的质量灵敏度估计为0.89 pg Hz−1，优于标准TG方法。我们用CuSO_4·5 H_2 O晶体测试了MMTG的性能。尽管所得的热重曲线偏离了商用热重仪测得的CuSO 4·5 H2O标准热重曲线，但最终的质量损失率与理论预期值相符。我们将这种偏差归因于金属丝微加热器固有的温度不均匀性、非等温条件和温度梯度。有限元（FE）模拟进行，以确认和深入了解的非均匀加热现象的微加热器和样品。基于模拟结果，我们提出了可以实现的设计，使MEMS TG成为一个成功的企业。
Micro/nano thermogravimetry (TG) employing MEMS has significant potential to improve the minimum sample mass and mass resolution as compared to commercial TG instruments. Although there have been a few previous reports on MEMS TG, none of them have critically analysed the obtained TG curve in detail. In this work, we have designed and fabricated a microelectromechanical thermogravimetric device (MMTG) with integrated microheaters and temperature sensors. The mass sensitivity of the device was estimated to be 0.89 pg Hz−1 which outperforms the standard TG approaches. We tested the MMTG performance with CuSO4·5H2O crystals. The final mass loss ratio corresponds to the theoretically expected value, although the obtained TG curve deviated from the standard TG curve of CuSO4·5H2O obtained from commercial TG instruments. We attributed the deviation to the inherent temperature non-uniformity, non-isothermal conditions and temperature gradients of metallic-wire based microheaters. Finite element (FE) simulations were carried out in order to confirm and gain insights into the non-uniform heating phenomena of microheater and sample. Based on the simulation results, we propose designs that can be realized to make MEMS TG a successful enterprise.