Durable Perovskite UV Sensor Based on Engineered Size-Tunable Polydimethylsiloxane Microparticles Using a Facile Capillary Microfluidic Device from a High-Viscosity Precursor

In this work, size-tunable polydimethylsiloxane (PDMS) microparticles are fabricated from a high-viscosity oil phase using a facile coflowing capillary microfluidic device and optimized aqueous phase composition. The dispersity of the microparticle size is tuned by engineering of the viscosity of the continuous phase and flow rate ratio that leads us to achieve monodisperse microparticles. Regarding the high potential of the PDMS microparticles for optical applications, efficient environmentally durable perovskite-based UV sensors are fabricated employing the designed size-tunable microparticles. Surprisingly, the UV sensors comprising CH 3 NH 3 PbBr 3 perovskite quantum dots as UV-sensitive nanocrystals embedded in transparent PDMS microparticles are water resistant because of the high hydrophobicity of PDMS. Remarkably, the UV sensors show a photoluminescence quantum yield as high as 75% that can be employed effortlessly as reusable leak detectors in different fluidic working systems.