Interfacial modification as a feasible strategy to improve the properties of perovskite solar cells (PSCs) has been widely studied in recent years. In this work, PbCl 2 modification at the interface of SnO 2 /CH 3 NH 3 PbI 3 was used for CH 3 NH 3 PbI 3 -based planar PSCs. The introduction of PbCl 2 between SnO 2 and CH 3 NH 3 PbI 3 layers boosted the crystallization of perovskite film, which promoted the photovoltaic properties of corresponding PSCs. The open circuit voltage ( V OC ) and fill factor (FF) of the PbCl 2 -modified devices (1 mg/mL) were 1.11 V and 0.79, respectively, which were both higher than those of the reference devices without PbCl 2 (1.04 V and 0.76). Moreover, a steady-state power output efficiency exceeding 19% was obtained for the PbCl 2 -modified devices (1 mg/mL), which implied that PbCl 2 modification was an effective and low cost strategy for efficient PSCs.
Antimony chalcogenide is a promising absorber material for photovoltaic (PV) cells because of its tunable band gap, strong optical absorption, earth-abundant, and nontoxic constituents. Here, a novel hydrazine-free approach for fabricating antimony chalcogenide films prepared via spray pyrolysis deposition with further selenylation, as well as high performance solar cells are reported. The fabricated antimony chalcogenide solar cells exhibits remarkably high open-circuit voltage ( V OC ) comparing with that of Sb 2 Se 3 and Sb 2 S 3 devices. The distribution of Se during the selenylation process via refering to the Fick's second law is discussed. The results show that the selenized absorber has tremendously improved absorbance for visible light and a cascade-type energy level from surface to bulk, resulting in an ideal energy level matching for p-n junction. By introducing an efficient buffer layer, the detrimental short-circuit is avoided by reducing the cracks. Finally, 4.57% of the power conversion efficiency (PCE) of the solar cell is achieved. Furthermore, a module with a large-scale active area of 21 cm 2 is successfully fabricated, which shows a PCE of 3.19%, and a V OC of 3.42 V. The present work suggests that the antimony chalcogenide solar cells are promising for industrial application.
You Liu,Fang Liu,Jungan Wang,Hongyan Huang,Suhao Yan,Song Gao,Lin Wang,Wei Huang,Tianshi Qin
Wide-bandgap photovoltaics (WBPV) could not only provide electrical energy by photoelectronic conversion of the invisible part of the solar spectrum, but also usually had the unique advantage of high open circuit voltage ( V oc). In this work, we reported a novel HTM based on tetrakis (N-phenothiazine) Spirobifluorene (Spiro-PT), its HOMO energy level could be well matched with MAPbBr 3 perovskite HOMO energy level. This HTM could effectively suppress nonradiative recombination, which leads to an increase in the photovoltage of WBPV to more than 1.41 V. As a result, the n-i-p mesoscopic structured WBPV achieved a champion PCE of 7.36% as well as excellent operational stability exhibiting 91% of initial efficiency after 500 h continuous illumination without encapsulation. Based on the high V oc of the MAPbBr 3 /Spiro-PT device, the photovoltaic electrochromic device showed a response speed (the average coloring time was 40 s and the bleaching time was 272 s) and high average visible light transmittance contrast (about 37% in 450–780 nm), the corresponding electrochromic device with maximum dynamic contrast up to 46% at 600 nm between bleached and colored states. This WBPV-powered electrochromic system could provide a pathway towards stand-alone smart window technique for future energy-saving buildings.