Moth-eye Structured Polydimethylsiloxane Films for High-Efficiency Perovskite Solar Cells

Large-area polydimethylsiloxane(PDMS)films with variably sized moth-eye structures were fabricated to improve the efficiency of perovskite solar cells.An approach that incorporated photolithography,bilayer PDMS deposition and replication was used in the fabrication process.By simply attaching the moth-eye PDMS films to the transparent substrates of perovskite solar cells,the optical properties of the devices could be tuned by changing the size of the moth-eye structures.The device with 300-nm moth-eye PDMS films greatly enhanced power conversion efficiency of ~21 % due to the antireflective effect of the moth-eye structure.Furthermore,beautiful coloration was observed on the 1000-nm moth-eye PDMS films through optical interference caused by the diffraction grating effect.Our results imply that moth-eye PDMS films can greatly enhance the efficiency of perovskite solar cells and building-integrated photovoltaics.

Patterning of Metal Halide Perovskite Thin Films and Functional Layers for Optoelectronic Applications

In recent years,metal halide perovskites have received significant attention as materials for next-generation optoelectronic devices owing to their excellent optoelectronic properties.The unprecedented rapid evolution in the device performance has been achieved by gaining an advanced understanding of the composition,crystal growth,and defect engineering of perovskites.As device performances approach their theoretical limits,effective optical management becomes essential for achieving higher efficiency.In this review,we discuss the status and perspectives of nano to micron-scale patterning methods for the optical management of perovskite optoelectronic devices.We initially discuss the importance of effective light harvesting and light outcoupling via optical management.Subsequently,the recent progress in various patterning/texturing techniques applied to perovskite optoelectronic devices is summarized by categorizing them into top-down and bottom-up methods.Finally,we discuss the perspectives of advanced patterning/texturing technologies for the development and commercialization of perovskite optoelectronic devices.

Ultrasensitive and Highly Stretchable Multiple‑Crosslinked Ionic Hydrogel Sensors with Long‑Term Stability

Flexible hydrogels are receiving significant attention for their application in wearable sensors.However,most hydrogel materials exhibit weak and one-time adhesion,low sensitivity,ice crystallization,water evaporation,and poor self-recovery,thereby limiting their application as sensors.These issues are only partly addressed in previous studies.Herein,a multiplecrosslinked poly(2-(methacryloyloxy)ethyl)dimethyl-(3-sulfopropyl)ammonium hydroxide-co-acrylamide)(P(SBMA-co-AAm))multifunctional hydrogel is prepared via a one-pot synthesis method to overcome the aforementioned limitations.Specifically,ions,glycerol,and 2-(methacryloyloxy)ethyl)dimethyl-(3-sulfopropyl)ammonium hydroxide are incorporated to reduce the freezing point and improve the moisture retention ability.The proposed hydrogel is superior to existing hydrogels because it exhibits good stretchability(a strain of 2900%),self-healing properties,and transparency through effective energy dissipation in its dynamic crosslinked network.Further,2-(methacryloyloxy)ethyl)dimethyl-(3-sulfopropyl)ammonium hydroxide as a zwitterion monomer results in an excellent gauge factor of 43.4 at strains of 1300-1600%by improving the ion transportability and achieving a strong adhesion of 20.9 kPa owing to the dipole-dipole moment.The proposed hydrogel is promising for next-generation biomedical applications,such as soft robots,and health monitoring.