Simple Template Synthesis Of Zinc Oxide Hierarchical Structure And Long-chain Alcohol-sensitive Properties

Long-chain alcohols are a common class of flammable and explosive volatile organic compounds(VOCs)that are widely used as solvents and raw materials,and their leakage poses serious threats to environment,human health and public safety.In particular,the air mixtures of flammable and high-energetic long-chain alcohols can lead to intense combustion and explosion when exposing to open fire or high temperature,and its combustion product is highly asphyxiating CO and CO₂ gases.However,the currently reported ZnO-based n-butanol sensors still still suffer from the defects of high working temperature,low response and high limit of detection,and even the detection of n-pentanol and n-hexanol vapors has not been reported in the literature so far.Therefore,it is necessary to develop ZnO-based sensing materials for fast and accurate detection of long-chain alcohol vapors.Therefore,in this dissertation,mesoporous ZnO microtubules,multi-stage porous ZnO microtubules and keel-type ZnO fibers were separately prepared through simple zinc salt impregnation and air calcination method using natural rose stems(RS),poplar branch(PB)and waste cigarette butts(CBs)as template.The composition and microstructure of these materials were characterized in detail by means of TG,IR,XRD,SEM,TEM,BET,etc.,and the influence of calcination temperature on the morphology and gas-sensing performance of these hierarchical ZnO structures was also discussed.The gas-sensing mechanism of sensors to long-chain alcohol vapors was carefully analyzed in detail by XPS technique.The results show that the above three types of hierarchical ZnO materials have realized highly sensitive and fast response to trace long-chain alcohol vapors.Especially,the keel-type ZnO fibers synthesized from discarded CB template show high response and good linear relationship to alcohol vapor with different lengths of alkyl chains,indicating certain differential ability in detecting the same concentration of diverse long-chain alcohols vapors and potential practical applications.Therefore,the simple template strategy in this dissertation will provide new avenue for future controllable fabrication of other hierarchically structured gas-sensing materials.