Thermally-enhanced photo-electric response of an organic semiconductor with low exciton binding energy for simultaneous and distinguishable detection of light and temperature

• 作者: Yongxu Hu Li Yu Yinan Huang Zhongwu Wang Shuguang Wang Xiaosong Chen Deyang Ji Huanli Dong Jie Li Yajing Sun Liqiang Li Wenping Hu
• 来源期刊: 中国科学：化学（英文版）
• 年，卷（期）: 2022,（1）
• 所属期刊栏目: ARTICLES
• 页码范围: 145-152
• 页数: 8页
• 语种: 英文

摘要

Simultaneous and distinguishable detection of external stimuli such as light and temperature is of great interest for a variety of scientific and industrial applications.Theoretically,an organic semiconductor with low exciton binding energy,low thermal activation energy and good charge transporting property produces thermally enhanced photo-electric response in organic phototransistors (OPTs),which thus provides an ideal and effective way to realize the simultaneous and distinguishable detection of temperature and light.However,there is no report on such a kind of organic semiconductor until now.Herein,we designed and synthesized a narrow band gap organic small molecule semiconductor 2,5-bis(2-butyloctyl)-3,6-bis(5-(4-(diphenylamino)phe-nyl)thiophen-2-yl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione (DPP-T-TPA) with low exciton binding energy (about 37 meV)and small activation energy (about 61 meV) for distinct thermal-dependence of charge carrier and exciton.The low exciton binding energy enables the semiconductor to exhibit strong thermal dependence of exciton dissociation,which contributes to the thermally-enhanced photo-electric response.Furthermore,the low thermal activation energy produces the weak thermal de-pendence of charge transport,which avoids the disturbance of thermally-modulated charge transport on photo-electric response.Benefiting from these two features,phototransistors based on DPP-T-TPA show great potential in simultaneous and distin-guishable detection of light and temperature,which represents a novel and efficient way for bifunctional detection.