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Maintaining the power conversion efficiency (PCE) of perovskite solar cells (PSCs) while enlarging the active area is necessary for their industrialization, where the key part is the uniform carrier extraction. Here, a conformal electron transport layer (ETL) is reported with eliminated low‐conductive contacts through a tailored deposition that combines chemical bath deposition and modified spin‐coating on a light‐managing textured substrate. The KPFM and C‐AFM are utilized to prove the uniform and optimized electrical properties. This study further employs the 2D measurements of PL and TRPL mapping to focus on revealing the enhanced uniformity of electron extraction. The uniform ETL conductivity and electron extraction contribute to a substantial decrease in device up‐scaling losses, making the δPCE (PCE0.08−PCE1PCE0.08)$\frac{{{\mathrm{PC}}{{{\mathrm{E}}}_{0.08}} - {\mathrm{PC}}{{{\mathrm{E}}}_1}}}{{{\mathrm{PC}}{{{\mathrm{E}}}_{0.08}}}})\ $ between 0.08 cm2‐device and 1 cm2‐device decrease from 5.02% to 2.97%, while the perovskite film is deposited using two‐step method. When using one‐step method to deposit perovskite film, PCEs of 25.13% and 23.93% for the active area of 0.08 cm2 and 1 cm2 are achieved, and the δPCE decreases from 7.89% to 4.77%, validating the significant effects on reducing up‐scaling losses. This work provides a new perspective to maintain high efficiency while device up‐scaling, providing more opportunities to push forward the PSCs industrialization. [ABSTRACT FROM AUTHOR]

Metal‐halide perovskite solar cells (PSCs) have emerged as a promising photovoltaic technology. Fabricating PSCs in ambient air can accelerate their low‐cost commercialization, since it can remove the reliance on atmosphere‐controlled equipment. However, the power conversion efficiency (PCE) of air‐fabricated PSCs still lags behind those fabricated in glovebox. Here, based on a technology to fabricate high‐quality perovskite film in ambient air, a compatible optimization is performed on electron transport layer (ETL) to further enhance the photovoltaic performance of PSCs. A soft‐templated deposition strategy is proposed that utilizes tetrasodium glutamate diacetate (GLDA) to finely regulate the chemical bath deposition process, leading to an ideal SnO2 ETL with no additive residual. Adopting this feature of no residual, a molecular bridge using β‐guanidinopropionic acid (βA) is constructed at the buried interface (SnO2/perovskite), which effectively enhances the electron extraction and decreases electron losses. The resulting PSCs (0.08 cm2) achieve an impressive PCE of 25.74% (certificated 25.43%), which is the highest among the air‐fabricated PSCs reported to date. A PCE of 24.61% in 1 cm2‐PSCs is also obtained, exhibiting the scalable potential of the technology. In addition, the excellent operational stability of these PSCs is also demonstrated. [ABSTRACT FROM AUTHOR]

The commercialization of perovskite solar cells is badly limited by stability, an issue determined mainly by perovskite. Herein, inspired by a natural creeper that can cover the walls through suckers, we adopt polyhexamethyleneguanidine hydrochloride as a molecular creeper on perovskite to inhibit its decomposition starting from the annealing process. The molecule possesses a long-line molecular structure where the guanidinium groups can serve as suckers that strongly anchor cations through multiple hydrogen bonds. These features make the molecular creeper can cover perovskite grains and inhibit perovskite decomposition by suppressing cations' escape. The resulting planar perovskite solar cells achieve an efficiency of 25.42% (certificated 25.36%). Moreover, the perovskite film and device exhibit enhanced stability even under harsh damp-heat conditions. The devices can maintain >96% of their initial efficiency after 1300 hours of operation under 1-sun illumination and 1000 hours of storage under 85% RH, respectively. The decomposition of perovskite materials during annealing could impact on their stability. Here, the authors adopt a molecular creeper to inhibit perovskite decomposition by suppressing the escape of cations, achieving certified efficiency of 25.36% for solar cells with operational stability. [ABSTRACT FROM AUTHOR]

The doped organic hole transport layer (HTL) is crucial for achieving high‐efficiency perovskite solar cells (PSCs). However, the traditional doping strategy undergoes a time‐consuming and environment‐dependent oxidation process, which hinders the technology upgrades and commercialization of PSCs. Here, we reported a new strategy by introducing a cascade reaction in traditional doped Spiro‐OMeTAD, which can simultaneously achieve rapid oxidation and overcome the erosion of perovskite by 4‐tert‐butylpyridine (tBP) in organic HTL. The ideal dopant iodobenzene diacetate was utilized as the initiator that can react with Spiro to generate Spiro⋅+ radicals quickly and efficiently without the participation of ambient air, with the byproduct of iodobenzene (DB). Then, the DB can coordinate with tBP through a halogen bond to form a tBP‐DB complex, minimizing the sustained erosion from tBP to perovskite. Based on the above cascade reaction, the resulting Spiro‐based PSCs have a champion PCE of 25.76 % (certificated of 25.38 %). This new oxidation process of HTL is less environment‐dependent and produces PSCs with higher reproducibility. Moreover, the PTAA‐based PSCs obtain a PCE of 23.76 %, demonstrating the excellent applicability of this doping strategy on organic HTL. [ABSTRACT FROM AUTHOR]

Mixed 2D/3D perovskite solar cells (PSCs) show promising performances in efficiency and long‐term stability. The functional groups terminated on a large organic molecule used to construct 2D capping layer play a key role in the chemical interaction mechanism and thus influence the device performance. In this study, 4‐(trifluoromethyl) benzamidine hydrochloride (TFPhFACl) is adopted to construct 2D capping layer atop 3D perovskite. It is found that there are two mechanisms synergistically contributing to the increase of efficiency: 1) The TFPhFA+ cations form a dipole layer promoting the interfacial charge transport. 2) The suppressed nonradiative recombination of perovskite through the coordination of TFPhFA+ cations with Pb–I octahedron, as well as the recrystallization of 3D perovskite induced by Cl‐ ions. As a result, the PSC delivers an efficiency of 24.0% with improved open‐circuit voltage (VOC) of 1.16 V, short‐circuit current density (JSC) of 25.42 mA cm‐2, and fill factor of 81.26%. The device shows no decrease in efficiency after 1500 h stored in the air indicating the good stability. The utilization of TFPhFACl not only provides a facile way to optimize the interfacial problems, but also gives a new perspective for rational design of large spacer molecule for constructing efficient 2D/3D PSCs. [ABSTRACT FROM AUTHOR]

Further performance enhancement of perovskite solar cells (PSCs) is limited by the defect‐assisted recombination losses. The approaches employed to decrease the losses contain defect passivation, perovskite crystallization control, interface engineering, etc. Herein, a new material of acetamidine thiocyanate (AASCN) via a facile method is synthesized, which exhibits dual functions combining a cation with passivation and an anion with crystallization. The iodine vacancies in the perovskite can be effectively passivated through hydrogen bonds formed by the NH bonds of the polar cation AA+. Furthermore, the pseudo‐halide anion SCN− can coordinate the Pb–I octahedrons, improving the perovskite film crystallization. Through vaporing the AASCN on perovskite films during the secondary crystal growth process, the defects mitigation and crystallization improvement are synergistically achieved. As a consequence, the FA0.25MA0.75PbI3 PSCs with AASCN achieve a power conversion efficiency of 23.17%, which is higher than that (21.43%) of untreated PSCs. In detail, the open‐circuit voltage has also a significant advancement from 1.095 to 1.167 V after the AASCN treatment. The design and synthesization of the multifunctional materials are supposed to provide a feasible approach for the performance improvement of PSCs. [ABSTRACT FROM AUTHOR]

High-crystalline-quality wide-bandgap metal halide perovskite materials that achieve superior performance in perovskite solar cells (PSCs) have been widely explored. Precursor concentration plays a crucial role in the wide-bandgap perovskite crystallization process. Herein, we investigated the influence of precursor concentration on the morphology, crystallinity, optical property, and defect density of perovskite materials and the photoelectric performance of solar cells. We found that the precursor concentration was the key factor for accurately controlling the nucleation and crystal growth process, which determines the crystallization of perovskite materials. The precursor concentration based on Cs0.05FA0.8MA0.15Pb(I0.84Br0.16)3 perovskite was controlled from 0.8 M to 2.3 M. The perovskite grains grow larger with the increase in concentration, while the grain boundary and bulk defect decrease. After regulation and optimization, the champion PSC with the 2.0 M precursor concentration exhibits a power conversion efficiency (PCE) of 21.13%. The management of precursor concentration provides an effective way for obtaining high-crystalline-quality wide-bandgap perovskite materials and high-performance PSCs. [ABSTRACT FROM AUTHOR]

In order to further optimize the solvothermal method for preparing Ti-doped CuGaS2 (CGS2:Ti) film, we have developed a simpler and rapider process of chemical synthesis for 30 min followed by annealing for 30 min. XRD, FESEM, EDAX, XPS, Raman spectra, UV–Vis–NIR absorption spectra and photoelectricity properties have been characterized. As a result, by partially replacing Ga atoms with Ti in the CGS2 chalcopyrite crystal, a narrow partially filled intermediate band (IB) was introduced, and two additional absorption bands were directly observed at 1.61 eV and 0.84 eV spectrum. A photoelectrochemical study of CGS2:Ti confirmed the broad-spectrum solar response produced by the IB effect. The present method is facile, does not need sulfuration process and large energy consumption, avoids the use of toxic substances and vacuum equipment, and may be a promising method for intermediate-band solar cells (IBSC). [ABSTRACT FROM AUTHOR]