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Abstract
Organic-inorganic hybrid perovskite (OIHP) has excellent photoelectronic properties such as long diffusion length, high absorption efficiency and tunable bandgap, which attract researchers’ attention and are considered as next-generation photoelectronic materials. The applications of this surprising material in photodetectors and resistive radon access memory (ReRAM) devices are reviewed in this thesis. However, some issues like poor stability and low carrier mobility still limit its further exploration. Therefore, a novel microwave-assisted synthesis method is firstly applied in cooperation of high-mobility single wall carbon nanotubes (SWCNTs) and MAPbBr3 perovskite single crystals to improve the charge transport property. By comparing crystals of conventional heating and microwave heating, microwave heating is demonstrated as promising processing method for perovskite single crystal synthesis with narrow particle size distribution and better crystallinity. Three groups of MAPbBr3/SWCNT single crystals with CNT weight concentration vary from 0% to 0.002% are fabricated through microwave heating. Raman spectra demonstrates surprising lattice expansion. Both scanning electron microscope (SEM) images and photoluminescence (PL) mapping prove the uniform separation of SWCNT bundles in perovskite single crystals. Besides, the PL quenching and time-resolved photoluminescence (TRPL) measurement demonstrated the enhanced charge transfer between SWCNT and MAPbBr3. Through electronic test, the carrier mobility of MAPbBr3/SWCNT single crystals is dramatically improved to 298 cm2/(V·s). On the other hand, extremely fast response speed and enhanced responsivity are obtained in such mixed perovskite-based photoconductors. The higher absorbance at high wavelength regime should attribute to excellent light absorption of SWCNTs. Overall, the positive effects of SWCNT to hybrid perovskite single crystals on charge transport and optoelectronic properties are demonstrated in this thesis, and the potential of this novel microwave heating method deserves further investigation on the other perovskite composite synthesis.