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Microheaters have drawn extensive attention for their substantial applications in thermotherapy, gas sensors, thin film preparation, biological research, etc. In plant physiology, uncovering the mechanisms by which plants sense and respond to environmental temperature fluctuations will help us better understand the impact of climate change on crop yield and ecosystem resilience. Currently, microheaters with long-term heating capability have rarely been applied to investigate plant thermal responses. In this study, we applied a direct writing technique to fabricate microheaters suitable for studying plant thermal biology with silver conductive ink. The optimal printing conditions and the heating performance (e.g., stability, durability, reusability) of the printed heaters were thoroughly characterized. The printed microheaters can provide stable and constant heating to plant organs for over four days. When placed near plant leaves to create localized heating, the microheater could successfully activate the expression of a thermoresponsive marker gene in plants. These results demonstrate the potential of applying printed microheaters to study plant thermal biology at the organ and tissue level.
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Bubble-Printed Microscale Silver Thermistors
Microscale temperature sensing and control are essential in various applications. Thermistors are widely utilized for temperature sensing owing to their simple design and high sensitivity. The future of thermistors lies in miniaturization and integration in highly customizable and sustainable electronics. Moreover, the ever-reducing size of the transistors requires the thermistors to scale down proportionally, without any compromise to its functionality. However, fabricating microscale thermistors exhibiting high accuracy and repeatable measurements has been challenging for state-of-the-art device miniaturization. Here, we develop versatile printing of microscale thermistors from silver fluoride solution by exploiting laser-induced opto-thermal microbubbles. The microscale temperature gradients on the bubble surface create an enhanced concentration of silver ions around the bubble to enable high-resolution printing of submicrometer structures with low-concentration precursors and low wastage. We demonstrate the bubble printing of thermistor arrays with both positive and negative thermal coefficients by exploiting the size effect on the electrical conductivity. We further investigate the sensing performance and long-term stability of the printed thermistors and conclude that the bubble-printed thermistors exhibit high-resolution sensing capabilities with long-term stability, promising enhanced performance in medical and semiconductor applications.
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- Award ID(s):
- 2140985
- PAR ID:
- 10563138
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- The Journal of Physical Chemistry C
- Volume:
- 128
- Issue:
- 17
- ISSN:
- 1932-7447
- Page Range / eLocation ID:
- 7316 to 7322
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acs.jpcc.4c00598
