adWe present a facile mechanochemical route for the preparation of hybrid CH3NH3PbI3 (MAPbI3) perovskite particles with the size of several hundred nanometers for high-efficiency thin-film photovoltaics. Powder X-ray diffraction measurements demonstrates that mechanosynthesis is a suitable strategy to produce highly crystalline CH3NH3PbI3 material showing no detectable amounts of the starting CH3NH3I and PbI2 reagents. Thermal stability measurements based on thermogravimetric analysis data of mechanosynthesized perovskite particles, indicated that the as-grounded MAPbI3 are stable up to 300°C with no detectable material loss at lower temperatures. Optical properties of newly synthesized perovskite particles were characterized by applying steady state absorption and fluorescence spectroscopy, which confirmed a direct band band-gap of 1.48eV. Time resolved single photon counting measurements revealed that 70% of charges undergo recombination with a 61 ns lifetime. The solar cell devices made from mechanosynthesized perovskite particles achieved a power conversion efficiency of 9.1% when applying a one step deposition method.

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Mechanochemistry has recently emerged as an environmentally friendly solventless synthesis method enabling a variety of transformations including those impracticable in solution. However, its application in the synthesis of well-defined nanomaterials remains very limited. Here, we report a new bottom-up mechanochemical strategy to rapid mild-conditions synthesis of organic ligand-coated ZnO nanocrystals (NCs) and their further host-guest modification with β-cyclodextrin (β-CD) leading to water-soluble amide-β-CD-coated ZnO NCs. The transformations can be achieved by either one-pot sequential or one-step three-component process. The developed bottom-up methodology is based on employing oxo-zinc benzamidate, [Zn4 (μ4 -O)(NHOCPh)6 ], as a predesigned molecular precursor undergoing mild solid-state transformation to ZnO NCs in the presence of water in a rapid, clean and sustainable process.