Facile Fabrication of Large-Area and High-Quality Organic–Inorganic Hybrid Perovskite Ferroelectric Films Through Electrohydrodynamic Printing

Traditional oxide ferroelectrics have long struggled to produce flexible, large-area, and high-quality thin films at low temperatures, despite their good piezoelectric activity. Organic–inorganic hybrid perovskite ferroelectrics (OIHPFs), by contrast, are gaining popularity as promising candidates for next-generation flexible self-powered electric devices due to their easy solution-processability, structural adjustability, mechanical flexibility, and superior piezoelectric performance. However, their practical use is hindered by a lengthy single-crystal growing period and the absence of a truly effective large-area film manufacturing technique. To address these challenges, a simple electrohydrodynamic (EHD) printing technology is first proposed to in situ manufacture large-area, high-quality OIHPF crystals or flexible films at low temperatures, without substrate or size limitations. The obtained TMCM-CdBrCl₂ film has a high coverage of 99.83%. Notably, it has a crystallinity of 80.35% and a superior piezoelectric coefficient that is 72% and 5.8 times higher than that of the non-EHD-printed sample, respectively. The flexible piezoelectric nanogenerator (PENG) based on this film can endure over 200 000 bending cycles—the highest value recorded to date. This approach also shows strong feasibility and broad applicability in creating different OIHPF films or crystals, providing valuable scientific insight for the large-scale and integrated development of flexible OIHPF-based electronics.