Abstract: A method of forming a Pb-free perovskite film is provided, the method based on vacuum evaporation and comprising: first depositing a first material comprising Sn halide on a substrate to form a first layer; second depositing a second material comprising organic halide to form a second layer on the first layer to obtain a sequentially-deposited two-layer film on the substrate; and annealing the sequentially-deposited two-layer film on the substrate. During the annealing, the first and second materials inter-diffuse and react to form the Pb-free perovskite film. The second layer is formed to cover the first layer so as to prevent the first layer from air exposure. The solar cell device including the Pb-free perovskite film formed by using the present method exhibits good stability.

Abstract: An optoelectronic device is provided, the device comprising an active layer comprising organometal halide perovskite and a hole transport layer (HTL) formed by vacuum evaporation and configured to transport hole carriers. The HTL includes a first sublayer comprising a hole transport material (HTM) doped with an n-dopant and disposed adjacent to the active layer, a second sublayer comprising the HTM that is undoped and disposed adjacent to the first sublayer, and a third sublayer comprising the HTM doped with a p-dopant and disposed adjacent to the second sublayer. The doping concentration of the n-dopant for the n-doped sublayer is determined to match the highest occupied molecular orbital energy level of the n-doped sublayer with the valence band maximum energy level of the perovskite active layer.

Abstract: An optoelectronic device is provided, the device comprising an active layer comprising organometal halide perovskite and a hole transport layer (HTL) formed by vacuum evaporation and configured to transport hole carriers. The HTL includes a first sublayer comprising a hole transport material (HTM) doped with an n-dopant and disposed adjacent to the active layer, a second sublayer comprising the HTM that is undoped and disposed adjacent to the first sublayer, and a third sublayer comprising the HTM doped with a p-dopant and disposed adjacent to the second sublayer. The doping concentration of the n-dopant for the n-doped sublayer is determined to match the highest occupied molecular orbital energy level of the n-doped sublayer with the valence band maximum energy level of the perovskite active layer.

Abstract: A method of forming a Pb-free perovskite film is provided, the method based on vacuum evaporation and comprising: first depositing a first material comprising Sn halide on a substrate to form a first layer; second depositing a second material comprising organic halide to form a second layer on the first layer to obtain a sequentially-deposited two-layer film on the substrate; and annealing the sequentially-deposited two-layer film on the substrate. During the annealing, the first and second materials inter-diffuse and react to form the Pb-free perovskite film. The second layer is formed to cover the first layer so as to prevent the first layer from air exposure. The solar cell device including the Pb-free perovskite film formed by using the present method exhibits good stability.

Abstract: An optoelectronic device is provided, the p-doped HTL device comprising an active layer comprising organometal halide perovskite and a hole transport layer (HTL) formed by vacuum evaporation and configured to transport hole carriers. The HTL includes a first sublayer comprising a hole transport material (HTM) doped with an n-dopant and disposed adjacent to the active layer, a second sublayer comprising the HTM that is undoped and disposed adjacent to the first sublayer, and a third sublayer comprising the HTM doped with a p-dopant and disposed adjacent to the second sublayer. The doping concentration of the n-dopant for the n-doped sublayer is determined to match the highest occupied molecular orbital energy level of the n-doped sublayer with the valence band maximum energy level of the perovskite active layer.