In this work, the pseudohalide thiocyanate has been demonstrated as a promising alternative to the halide anion to engineer optoelectronic properties of inorganic/ organic hybrid perovskites because it exhibits better...In this work, the pseudohalide thiocyanate has been demonstrated as a promising alternative to the halide anion to engineer optoelectronic properties of inorganic/ organic hybrid perovskites because it exhibits better chemical stability than the halide anion. Previous reports have suggested that the ionic radii and electronegativity of SCN- is close to that of I^-; the SCN^- doped CH3NH3PbI3 exhibited similar optical properties as pure CH3NH3PbI3. Consequently, it was expected that doping of CsPbBr3 perovskite with SCN^- would result in band gap narrowing. Interestingly, the photoluminescent all-inorganic CsPbBr3 perovskite nanocrystals exhibit an abnormal blue shift in optical properties and improvement of the crystallinity when successfully doped by SCN^-. Combined experimental and theoretical investigations revealed that doping of the CsPbBr3 perovskite with the rod-like SCN^- anion introduced disorder in the crystal lattice, leading to its expansion, and impacted the electronic structure of the perovskite with band gap broadening.展开更多
基金This work was sponsored by the National Natural Science Foundation of China （Nos. 21475021, 21427807, 61722403, 11404131, and 11674121）, the Natural Science Foundation of Jiangsu Province （No. BK20141331）, the Fundamental Research Funds for the Central Universities, Program for JLU Science and Technology Innovative Research Team, the Special Fund for Talent Exploitation in Jilin Province of China, Jiangsu provincial financial support of fundamental conditions and science and technology for people＇s livelihood for Jiangsu key laboratory of advanced metallic materials （No. BM2007204）.
文摘In this work, the pseudohalide thiocyanate has been demonstrated as a promising alternative to the halide anion to engineer optoelectronic properties of inorganic/ organic hybrid perovskites because it exhibits better chemical stability than the halide anion. Previous reports have suggested that the ionic radii and electronegativity of SCN- is close to that of I^-; the SCN^- doped CH3NH3PbI3 exhibited similar optical properties as pure CH3NH3PbI3. Consequently, it was expected that doping of CsPbBr3 perovskite with SCN^- would result in band gap narrowing. Interestingly, the photoluminescent all-inorganic CsPbBr3 perovskite nanocrystals exhibit an abnormal blue shift in optical properties and improvement of the crystallinity when successfully doped by SCN^-. Combined experimental and theoretical investigations revealed that doping of the CsPbBr3 perovskite with the rod-like SCN^- anion introduced disorder in the crystal lattice, leading to its expansion, and impacted the electronic structure of the perovskite with band gap broadening.
