Effects of Visible Light on Gas Sensors: From Inorganic Resistors to Molecular Material-Based Heterojunctions

Abstract

In the last two decades, many research works have been focused on enhancing the properties of gas sensors by utilising external triggers like temperature and light. Most interestingly, the light-activated gas sensors show promising results, particularly using visible light as an external trigger that lowers the power consumption as well as improves the stability, sensitivity and safety of the sensors. It effectively eliminates the possible damage to sensing material caused by high operating temperature or high energy light. This review summarises the effect of visible light illumination on both chemoresistors and heterostructure gas sensors based on inorganic and organic materials and provides a clear understanding of the involved phenomena. Finally, the fascinating concept of ambipolar gas sensors is presented, which utilised visible light as an external trigger for inversion in the nature of majority charge carriers in devices. This review should offer insight into the current technologies and offer a new perspective towards future development utilising visible light in light-assisted gas sensors.

Electrosynthesized fluorinated polybithiophenes for ammonia sensing

“…To avoid stability issues caused by an oxygen atmosphere, further studies with visible and near infrared light should be focused on, as recently reviewed. 63 Finally, fluorinated moieties lead to highly more stable sensors than the non-fluorinated polymers under our sensing conditions, in particular under a humid atmosphere. The copolymers reported here are less conductive than the pristine polymers, which gave us the opportunity to build heterojunctions.…”

Influence of pH on Room-Temperature Synthesis of Zinc Oxide Nanoparticles for Flexible Gas Sensor Applications

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