Abstract The mechanism of the innovative adsorption based field emission hydrogen sensing technique is investigated from experimental and first-principles investigations. Hydrogen pressure from 10 −3 to 10 −7 Pa range could be detected. High carbon nanotube (CNT) crystallinity plays key role for the reduction of the effective work function from the dissociated hydrogen adsorption, leading to the field emission current increase. For CNT emitters with high dangling-bond (DB) type of defects/structures, the dissociated H adsorption occurs preferentially on the DB site with negligible work function variation. Joule heating & temperature rising is a core factor to assist the dissociated hydrogen adsorption with enhanced sensing effect. For work function sensitive CNT devices, operations under hydrogen & high temperature conditions may produce performance stability issue.

中文翻译：

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基于碳纳米管场发射的低压氢传感：原子吸附诱导功函数效应的机制

摘要 通过实验和第一性原理研究，研究了基于吸附的创新型场发射氢传感技术的机理。可以检测到10 -3 到10 -7 Pa范围内的氢气压力。高碳纳米管 (CNT) 结晶度对于降低离解氢吸附的有效功函数起着关键作用，导致场发射电流增加。对于具有高悬空键 (DB) 类型缺陷/结构的 CNT 发射器，解离的 H 吸附优先发生在 DB 位点上，功函数变化可忽略不计。焦耳加热和升温是辅助解离氢吸附并增强传感效果的核心因素。对于功函数敏感的 CNT 器件，在氢气和