A robotic platform is adopted to conduct a comprehensive solvent engineering for making lead halide perovskites in a high-throughput manner. Deeper insights into the working mechanisms and selection criteria of antisolvents are investigated and summarized. In addition, a reliable antisolvent database is established, and verification tests match well with the theory. Furthermore, our work provides significant guidance for designing functional and environment-friendly mixed solvent systems to fabricate high-quality perovskite materials or devices.

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diodes, [3] electromagnetic shielding, [4] and organic photovoltaics. [5] Electrodes based on metallic nanowires (NWs) are among the most promising alternatives to indium tin oxide (ITO), which is currently the most efficient and widely used transparent conducting material. [6] Silver, the metal with the highest electrical conductivity, can be expected to provide the best network electrodes. [7] Indeed, silver nanowires (Ag NWs)-based percolating networks successfully combine high flexibility, high optical transparency, and high electrical conductivity. [8] Ag NWs electrode are also cost-efficient and compatible with large-scale manufacturing methods. [5a] However, they are very vulnerable to heat, light, oxygen, humidity, and sulfidation, limiting their usefulness for practical applications. [9] Solutions to these problems have been investigated and various methods were applied to protect the Ag NWs. [10] Recently, a SnO x shell was proposed as a solution to overcome the stability issues. [11] Zhao et al. reported the wet chemical synthesis of Ag NWs with a monolayer of SnO 2 under ambient conditions. [11a] This is achieved by introducing trace amounts of Sn 2+ to an Ag NWs dispersion, which form an oxide monolayer. This Transparent electrodes consisting of silver nanowires (Ag NWs) are a solution-processed alternative to commonly used indium tin oxide electrodes. Here, Ag NW electrodes protected by a tin oxide (SnO x ) are explored and unprecedented thermal stability is found. While unprotected Ag NW electrodes fail at 250 °C, the SnO x Ag NW electrodes remain stable for 40 h at 250 °C and withstand high temperatures up to 500 °C for short times. First, an optimized method of synthesis that provides uniform Ag NWs with high reproducibility is used. Afterward, a SnO x shell is formed in a wet chemical reaction. Fabrication of highly conductive electrodes requires thermal annealing at 300 °C for 5 min under ambient atmosphere. Electrodes with a sheet resistance as low as 20 Ω sq -1 and visible transmittance of 84% are demonstrated. It is shown that a ≈2 nm thick SnO x shell effectively protects the Ag NWs in a temperature range between 200 and 500 °C, whereas unprotected Ag NWs suddenly fail at temperatures beyond 200 °C. It is strongly anticipated that these improvements in the stability of Ag NWs open a large field of further investigations and applications.The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/aelm.202100787.

Flexible electrodes using nanowires (NWs) suffer from challenges of long-term stability and high junction resistance which limit their fields of applications. Welding via thermal annealing is a common strategy to enhance the conductivity of percolated NW networks, however, it affects the structural and mechanical integrity of the NWs. In this study we show that the decoration of NWs with an ultrathin metal oxide is a potential alternative procedure which not only enhances the thermal and chemical stability but, moreover, provides a totally different mechanism to reduce the junction resistance upon heat treatment. Here, we analyze the effect of SnOx decoration on the conductance of silver NWs and NW junctions by using a four-probe measurement setup inside a scanning electron microscope. Dedicated transmission electron microscopy analysis in plan-view and cross-section geometry are carried out to characterize the nanowires and the microstructure of the junctions. Upon heat treatment the junction resistance of both plain silver NWs and SnOx-decorated NWs is reduced by around 80%. While plain silver NWs show characteristic junction welding during annealing, the SnOx-decoration reduces junction resistance by a solder-like process which does not affect the mechanical integrity of the NW junction and is therefore expected to be superior for applications.