As a direct wide bandgap semiconductor,CsPbCl_(3)has great potential applications in the eld of near-ultraviolet photodetectors,lasers and higher-order multiphoton uores-cent detectors.In this work,we synthesized CsPb...As a direct wide bandgap semiconductor,CsPbCl_(3)has great potential applications in the eld of near-ultraviolet photodetectors,lasers and higher-order multiphoton uores-cent detectors.In this work,we synthesized CsPbCl_(3)micro/nanocrystals by vapor depo-sition method with CsCl and PbCl_(2)powders as the source materials.It was con rmed that the formation of CsPbCl_(3)perovskite through the chemical reaction of CsCl with PbCl_(2)occurred in the quartz boat before the source evaporation,not in vapor or on sub-strate surface.The evaporated CsPbCl_(3)can form micro/nanocrystals on substrate surfaces under appropriate conditions.Various morphologies including irregular polyhedrons,rods and pyramids could be observed at lower temperature,while stable and uniform CsPbCl_(3)single crystal microplatelets were controllably synthesized at 450℃.Prolonging the growth time could modulate the size and density of the microcrystals,but could not change the morphology.Substrate types made little di erence to the morphology of CsPbCl_(3)crystals.The photoluminescence spectra indicated that the crystallinity and morphology of CsPbCl_(3)micro/nanocrystals have signi cant e ects on their optical properties.The work is expected to be helpful to the development of optoelectronic devices based on individual CsPbCl_(3)microcrystal.展开更多
Fabricating high-quality cesium lead chloride(CsPbCl_3) perovskite nanowires(NWs) with dimension below 10 nm is not only of interests in fundamental physics, but also holds the great promise for optoelectronic applica...Fabricating high-quality cesium lead chloride(CsPbCl_3) perovskite nanowires(NWs) with dimension below 10 nm is not only of interests in fundamental physics, but also holds the great promise for optoelectronic applications. Herein, ultrathin CsPbCl_3 NWs with height of ～7 nm, have been achieved via vapor phase deposition method. Power and temperature-dependent photoluminescence(PL) spectroscopy is performed to explore the emission properties of the CsPbCl_3 NWs. Strong free exciton recombination is observed at ～3.02 eV as the temperature(T) is 78-294 K with binding energy of ～ 37.5 meV. With the decreasing of T, the PL peaks exhibit a first blueshift by 2 meV for T ～ 294-190 K and then a redshift by 4 meV for T ～ 190-78 K. The exciton–optical phonon interaction plays a major role in the linewidth broadening of the PL spectra with average optical phonon energy of ～48.0 meV and the interaction coefficient of 203.9 meV. These findings advance the fabrication of low dimensional CsPbCl_3 perovskite and provide insights into the photophysics of the CsPbCl_3 perovskite.展开更多
基金supported by the National Natu-ral Science Foundation of China(No.11575187)the National Key Research and Development Program(No.2016YFB0700205).
文摘As a direct wide bandgap semiconductor,CsPbCl_(3)has great potential applications in the eld of near-ultraviolet photodetectors,lasers and higher-order multiphoton uores-cent detectors.In this work,we synthesized CsPbCl_(3)micro/nanocrystals by vapor depo-sition method with CsCl and PbCl_(2)powders as the source materials.It was con rmed that the formation of CsPbCl_(3)perovskite through the chemical reaction of CsCl with PbCl_(2)occurred in the quartz boat before the source evaporation,not in vapor or on sub-strate surface.The evaporated CsPbCl_(3)can form micro/nanocrystals on substrate surfaces under appropriate conditions.Various morphologies including irregular polyhedrons,rods and pyramids could be observed at lower temperature,while stable and uniform CsPbCl_(3)single crystal microplatelets were controllably synthesized at 450℃.Prolonging the growth time could modulate the size and density of the microcrystals,but could not change the morphology.Substrate types made little di erence to the morphology of CsPbCl_(3)crystals.The photoluminescence spectra indicated that the crystallinity and morphology of CsPbCl_(3)micro/nanocrystals have signi cant e ects on their optical properties.The work is expected to be helpful to the development of optoelectronic devices based on individual CsPbCl_(3)microcrystal.
基金supported by National Natural Science Foundation of China(Nos.61774003,61521004,51472080)National Key Research and Development Program of China(Nos.2017YFA0205700,2017YFA0304600)+1 种基金Open Research Fund Program of the State Key Laboratory of Low-dimensional Quantum Physics(No.KF201706)Excellent Youth Foundation of Hubei Province(No.2017CFA038)
文摘Fabricating high-quality cesium lead chloride(CsPbCl_3) perovskite nanowires(NWs) with dimension below 10 nm is not only of interests in fundamental physics, but also holds the great promise for optoelectronic applications. Herein, ultrathin CsPbCl_3 NWs with height of ～7 nm, have been achieved via vapor phase deposition method. Power and temperature-dependent photoluminescence(PL) spectroscopy is performed to explore the emission properties of the CsPbCl_3 NWs. Strong free exciton recombination is observed at ～3.02 eV as the temperature(T) is 78-294 K with binding energy of ～ 37.5 meV. With the decreasing of T, the PL peaks exhibit a first blueshift by 2 meV for T ～ 294-190 K and then a redshift by 4 meV for T ～ 190-78 K. The exciton–optical phonon interaction plays a major role in the linewidth broadening of the PL spectra with average optical phonon energy of ～48.0 meV and the interaction coefficient of 203.9 meV. These findings advance the fabrication of low dimensional CsPbCl_3 perovskite and provide insights into the photophysics of the CsPbCl_3 perovskite.
