Room-temperature VOC detection using light-driven metal oxide heterojunctions: principles, challenges, and prospects.
Phibakordor Shangpliang1, Suraj Sunil Joshi1, Suresh D Kulkarni1
1Manipal Institute of Applied Physics, Manipal Academy of Higher Education Manipal Karnataka 576104 India choudhari.ks@manipal.edu.
Nanoscale Advances
|July 10, 2026
Summary
Semiconductor metal oxide (SMO) heterojunction sensors with light activation offer enhanced detection of volatile organic compounds (VOCs). These advanced sensors improve sensitivity and stability for environmental and medical applications.
Area of Science:
- Materials Science
- Chemical Sensing
- Nanotechnology
Background:
- Volatile organic compounds (VOCs) are critical pollutants and disease biomarkers.
- Developing highly sensitive VOC sensors is essential for environmental and health monitoring.
- Semiconductor metal oxide (SMO) sensors face limitations like temperature dependence and drift.
Purpose of the Study:
- To review advances in SMO heterojunction-based chemiresistive sensors for VOC detection.
- To highlight the role of light-activated sensing mechanisms in improving sensor performance.
- To explore applications in environmental monitoring, food quality, and medical diagnostics.
Main Methods:
- Comprehensive review of recent literature on SMO heterojunctions for VOC sensing.
- Analysis of basic sensing principles: bandgap engineering, charge transfer, heterojunction design.
- Discussion of light-activation strategies (UV and visible light) to overcome sensor limitations.
Main Results:
- SMO heterojunctions significantly enhance sensitivity, selectivity, response time, and stability compared to pristine SMOs.
- Light activation, particularly UV/visible, effectively mitigates temperature limitations and drift effects.
- Successful integration of these sensors with smart devices, IoT, wearables, and packaging for real-time monitoring.
Conclusions:
- SMO heterojunctions with light activation represent a promising pathway for advanced VOC sensing.
- Future directions include hybrid materials, flexible electronics, AI, and IoT integration for intelligent sensing.
- Overcoming challenges in stability, selectivity, and scalable fabrication is crucial for real-world deployment.
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