Fabrication of Cellulose Filters Incorporating Metal-Organic Frameworks for Efficient Nicotine Adsorption from Cigarette Smoke

Influence of Volatile Organic Compound Adsorption on the Characteristics of Organic Field-Effect Transistors and Rules for Gas-Sensing Measurements

Owing to the advantages of organic field-effect transistors (OFETs) in the versatility of organic synthesis, multiparameter measurement, and signal amplification, sensors based on OFETs have received increasing attention for detecting volatile organic compounds (VOCs). However, false device operation and gas-sensing measurements often occur to vitiate the advantages of OFETs and even output error gas-sensing signals. In this work, by experimentally and theoretically studying the effects of VOC adsorption on the operational characteristics of the OFET, the proper operations of OFETs in gas-sensing measurements were clarified. The multiparameter measurements of OFETs showed that the source-drain current was the optimized parameter for achieving high responsivity, and other OFET parameters could be used for fingerprint analysis. By operating OFETs in the near-threshold region, the amplification effect was switched to enhance the responsivity by orders of magnitude to VOCs, while in the overthreshold region, the OFETs had a low signal-to-noise ratio. Besides, a counteraction effect and an uncertainty effect were discovered, leading to error gas-sensing signals. A theoretical study was carried out to reveal the dependency of the gas-sensing properties of OFETs on VOC adsorption. A series of rules were proposed for guiding the measurements of OFET sensors by taking full advantage of transistors in gas-sensing applications.

Advanced Materials Design for Adsorption of Toxic Substances in Cigarette Smoke

Cigarettes, despite being economically important legal consumer products, are highly addictive and harmful, particularly to the respiratory system. Tobacco smoke is a complex mixture containing over 7000 chemical compounds, 86 of which are identified to have "sufficient evidence of carcinogenicity" in either animal or human tests. Thus, tobacco smoke poses a significant health risk to humans. This article focuses on materials that help reduce the levels of major carcinogens in cigarette smoke; these include nicotine, polycyclic aromatic hydrocarbons, tobacco-specific nitrosamines, hydrogen cyanide, carbon monoxide, and formaldehyde. Specifically, the research progress on adsorption effects and mechanisms of advanced materials such as cellulose, zeolite, activated carbon, graphene, and molecularly imprinted polymers are highlighted. The future trends and prospects in this field are also discussed. Notably, with advancements in supramolecular chemistry and materials engineering, the design of functionally oriented materials has become increasingly multidisciplinary. Certainly, several advanced materials can play a critical role in reducing the harmful effects of cigarette smoke. This review aims to serve as an insightful reference for the design of hybrid and functionally oriented advanced materials.