Lead‐free 2D antimony‐based halide perovskites with excellent optoelectronic properties, low toxicity, and good intrinsic stability are promising for photovoltaic devices. However, the power conversion efficiency (PCE) of antimony‐based perovskite solar cells (PSCs) is still lower than 3% due to the poor crystallinity and random orientation. Herein, it is found that the Cs3Sb2ClxI9‐x films prepared by adding methylamine chloride as an additive to the precursor solution can form a mixed intermediate phase with 0D dimer phase and 2D layered phase after low pressure treatment. During the annealing process, the 0D dimer phase will completely transition to 2D layered phase due to the partial replacement of I by Cl. Compared to adding SbCl3 directly, this method considerably increases the crystallinity of Cs3Sb2IxCl9‐x films. The obtained films have a preferential orientation along the (201) direction, which is beneficial for charge carrier transportation. Consequently, the champion device shows a PCE of 3.2%, which is one of the highest efficiencies achieved for inorganic Sb‐based PSCs with the n‐i‐p architecture to date.

Owing to the significant roles in balancing carrier transport, bandgap alignment, and perovskite crystallization, realizing high-quality electron transport layers (ETLs) and their effective electronic contact with the perovskite photoactive layer is crucial for future commercialization of perovskite solar cells (PSCs). Here, a high-quality SnO 2 ETL is firstly deposited at room temperature via the lowcost electron beam evaporation (E-beam) technology to help achieve an impressive PCE of 18.88% for rigid PSCs and a PCE of 15.73% for flexible devices. Then we introduced a novel passivating ligand molecule, 11 Maleimidoundecanoic acids (11MA), to help induce functional defects passivation at the interface of SnO 2 /Perovskite to coordinate with Pb 2+ in perovskite and Sn 4+ in SnO 2 via the functional groups (-C = O, -COOH). As a result, 11MA could help achieve the best PCE of 20.94% with negligible hysteresis for rigid devices. Also, doping 11MA in the perovskite photoactive layer further enhanced the PCE to 22.08% with much improved 2000 hours ambient stabilities. Finally, we fabricated different largearea rigid devices (10, 40, 100, and 600 mm 2 ) toward speeding up the commercialization of PSCs by industrial E-beam technology and rational defects passivation strategies.

inorganic semiconductors with a wide band gap, such as zinc oxide (ZnO), [7,8] titanium dioxide (TiO 2 ), [9,10] gallium nitride (GaN), [11,12] gallium oxide (Ga 2 O 3 ), [13,14] silicon carbide (SiC), etc. [15] However, the defect tolerance of these classic oxide semiconductors is relatively low, resulting in high dark current, low detectivity, and limiting their practical applications.Organic-inorganic perovskites with high defect tolerance have attracted extensive study in optoelectronic devices, [16][17][18][19][20] such as photovoltaics, [21,22] light-emitting diodes, [23,24] photodetectors,. [25,26] etc. As photodetectors, X-ray, ultraviolet-visible, and near-infrared light detection have been realized. [27][28][29] Chlorine-containing 3D perovskites with suitable bandgaps, such as MAPbCl 3 (MA + = CH 3 NH 3 + ) [30] and CsPbCl 3 , [31][32][33] were employed to detect ultraviolet light in the visible-blind range. However, the ion migration activation energy (E a ) of A-site and X-site ions in typical ABX 3 -based 3D perovskites is as low as ≈10-20 meV, [34,35] leading to poor intrinsic stability of 3D perovskite materials due to the migration of A-site and X-site ions. Therefore, it is necessary to develop stable perovskites for UV-PDs.Recently, 2D perovskites have emerged in the field of optoelectronic devices due to their excellent stability. [36,37] Compared with 3D perovskites, 2D perovskites have several advantages for photodetector devices: 1) the E a of 2D perovskites exceeds 200 meV, [38,39] which is much higher than the E a of 3D perovskite films, making 2D perovskites far more stable than 3D perovskites. 2) The resistivity of 2D perovskites is even as high as 10 12 Ω cm, which is much higher than typical MAPbX 3 (X = Cl, Br, I; 10 7 -10 8 Ω cm). [40] This is beneficial to reducing the dark current of the device, thereby improving the detectivity of the PD devices. 3) The Young's modules of 2D Ruddlesden-Popper (RP) perovskites can be compared to commonly used polymers, such as poly-methyl methacrylate (PMMA) and Nylon-6, which allow their utilization in flexible and wearable electronic devices. [41] Iodine and bromine-based 2D perovskites active layer have been used in photodetectors. [42] 2D RP perovskite (PEA) 2 MA 3 Pb 4 I 13 (PEA + = C 6 H 5 CH 2 CH 2 NH 3 + ) with ordered phase distribution was prepared for high performance self-powered photodetectors. [43] In general, iodine-based 2D perovskites Organic-inorganic perovskite photodetectors have drawn great attention due to their excellent performance and simple fabrication process. However, the detectivity of perovskite ultraviolet photodetectors (UV-PDs) is comparatively poor because of the high defect density in chlorine-containing 3D perovskites. Furthermore, 3D perovskites are easily degraded by high-energy ultraviolet light, limiting their practical applications. Herein, high quality quasi-2D Ruddlesden-Popper perovskite (Q-2DRPP) (PMA)

Hole transport layer (HTL)‐free carbon electrode‐based perovskite solar cells (C‐PSCs) have drawn great attention due to their excellent stability and simple fabrication process. However, the photovoltaic parameters of C‐PSCs usually exhibit large negative temperature coefficients (TCs). Herein, the TCs of C‐PSCs can be suppressed by enhancing electron extraction. An efficient electron transport layer (ETL), [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM)‐coated nanoneedle‐like brookite TiO2 (ND‐B‐TiO2) is used as ETL to prepare HTL‐free pure FAPbI3‐based C‐PSCs. Compared with bare ND‐B‐TiO2, PCBM@ND‐B‐TiO2 shows higher electron mobility, and better band alignment with formamidinium lead triiodide (FAPbI3) perovskite, as well as improved contact with perovskite, which leads to enhanced electron extraction and transportation. Consequently, the power conversion efficiency (PCE) of HTL‐free carbon‐based FAPbI3 PSC can reach up to 14.55%, which is one of the highest efficiencies for FAPbI3‐based planar C‐PSCs so far. More importantly, the optimized device is less sensitive to the operating temperature due to the boosted carrier extraction and passivated interface defects, showing a small TC(PCE) of only ≈−0.11%/°C between 25 °C and 85 °C. The work demonstrates that enhancing electron extraction is an effective way to achieve high‐performance C‐PSCs and high‐temperature solar cells.

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