Though CH3NH3PbBr3 single crystals are frequently applied in various optoelectronic devices due to their favorable cuboid geometry, superior optoelectronic properties, and better stability than CH3NH3PbI3, CH3NH3PbBr3 polycrystalline films normally show poorer morphology with scattered crystals than their iodide counterparts, inherently due to their different crystallization habits. In this work, a facile process based on a hot methylamine-based precursor with high viscosity and concentration is demonstrated to counteract rapid ion diffusion. The precursor also has special features including a large colloidal size, a solid form at room temperature, and fast crystallization offered by the easy evacuation of methylamine. CH3NH3PbBr3 films composed of tightly aligned CH3NH3PbBr3 cuboids on micron scale are obtained. Wide channel (100 μm) photodetectors made from the CH3NH3PbBr3 films show promising photoresponse and fast response speeds on par with those based on single crystals, suggesting high film quality and good optoelectronic connections between neighboring cuboids.

We describe a rare case of intraosseous Schwannoma in the foot involving the tarsal navicular, cuboid, all 3 cuneiforms, and the second and third metatarsal bases in a 50-year-old female. Radiographs revealed a large, well-defined osteolytic lesion with endosteal scalloping and trabeculated contours at the margins. Intralesional excision, allograft bone implantation, and Kirschner wire fixation were performed. The histologic and immunohistochemical studies confirmed the diagnosis of Schwannoma. The distinctive radiographic features might have been the result of tumor spreading within the nutrient canals of the bones and direct compression of bone as the tumor enlarged. At the 18-month follow-up point, the patient had recovered well without recurrence. Intralesional excision produced a good functional outcome; however, extensive fusion surgery is recommended.