柔性有机无机杂化pn结自驱动光电探测器及其应变调控机制研究

To fabricate flexible and self-powered nanodevices is a promising route to realize the miniaturization and functionalization of micro-nano electronics. Self-powered photodetectors utilize the built-in electrical field at the interface of semiconductor heterojunction to separate the photo-generated carriers. Utilizing piezopotential to modify the interface energy band structure is an advanced method to enhance the performance the piezoelectric nanomaterial based nanodevices. Because the strain always exists in flexible electronics, it is meaningful to investigate the performance modulation mechanism under strains. In this program, a series of flexible inorganic-organic hybrid self-powered photodetector was constructed with piezoelectric semiconductor of ZnO and MoS2 and p-type organic of PEDOT:PSS and Spiro-MeOTAD. The high carrier transportation of inorganic nanomaterials and the abundant electron structure and absorptivity of organic materials are combined with in these flexible device. The behavior of the device under strain is studied to investigate the modification regulation of the performance and the mechanism of the band structure variation and the electrons transport behavior at the inorganic-organic hybrid interface.

柔性和自供能是微纳电子器件向小型化和多功能化发展的重要趋势。自驱动光电探测器利用半导体异质结内建电场分离光生电子空穴对产生光电流，达到无源光探测的目的。采用压电半导体材料构建的光电器件中，通过应变产生的压电势调控界面能带结构是优化器件性能的重要手段。应变普遍存在于柔性器件中，因此研究应变调控柔性器件性能的基本规律和机理对发展柔性自驱动光电探测器具有重要意义。本项目拟采用低维压电半导体材料ZnO和MoS2与p型有机半导体材料PEDOT:PSS和Spiro-MeOTAD构建柔性自驱动光电探测器。将低维无机纳米材料高效载流子输运特性与有机半导体材料丰富的电子结构和高吸光率特性相结合。研究器件在应变下的服役行为，发现应变对器件性能的影响规律，揭示压电极化电场对有机无机杂化界面能带结构和结区载流子输运行为的调控机制。

本项目实现了大面积氧化锌阵列的密度和尺寸控制生长，建立了大尺寸MoS2、WSe2等二维半导体材料的CVD生长方法，建立了有机薄膜辅助精确转移和临界点干燥无损转移构筑柔性器件的新方法，构筑了多种混合维度、范德华异质结构柔性光电器件，发展了拉曼原位表征技术揭示应变对界面电荷与载流子输运行为调控规律的新方法。培养博士、硕士研究生5名，发表SCI论文25篇，包括Nature Energy、Nature Communication、Advanced Materials、ACS Nano、Nano Energy等。申请专利11项，授权2项。参与主办第十二届中美华人纳米论坛、第八届全国氧化锌学术会议等国际国内会议2次，参加国际国内会议作邀请报告十余次。负责人以第五完成人身份获得国家自然科学奖二等奖一项。