Flexible semitransparent perovskite solar cells (ST-PSCs)
have
great potential for use in high-density energy systems, such as building
or vehicle integrated photovoltaics, considering the great features
of PSC devices, including high performance, light weight, thin-film
processability, and high near-infrared transmittance. Despite numerous
efforts toward achieving efficiency and flexibility in ST-PSCs, the
realization of high-performance and operational stability in ST-PSCs
still require further development. Herein, we demonstrated the development
of highly efficient, stable, and flexible ST-PSCs using polyimide-integrated
graphene electrodes via a lamination-assisted bifacial cation exchange
strategy. A high-quality perovskite layer was obtained through the
cation exchange reaction using the lamination process, and ST-PSCs
with 15.1% efficiency were developed. The proposed ST-PSC device also
demonstrated excellent operational stability, mechanical durability,
and moisture stability owing to the chemically inert and mechanically
robust graphene electrodes. This study provides an effective strategy
for developing highly functional ST-perovskite optoelectronic devices
with high-performance and long-term operational stability.
The lack of highly impermeable and highly flexible encapsulation materials is slowing the development of flexible organic solar cells. Here, a transparent and lowtemperature synthetic alumina single layer is suggested as a highly impermeable and a highly flexible encapsulation material for organic solar cells. While the water vapor transmission rate (WVTR) is maintained up to 100,000 bending cycles for a 25 mm bending radius (corresponding to 8.1% of the elastic deformation limit), as measured by in situ tensile testing with free-standing 50 nm-thick alumina films, the WVTR degraded gradually depending on the bending radius and bending cycles for bending radii less than 25 mm. The degradation of the WVTR in cyclic deformation within the elastic deformation limit is investigated, and it is found to be due to the formation of pinholes by a bond-switching mechanism. Also, encapsulated organic solar cells with alumina films are found to maintain 80% of initial efficiency for 2 weeks even after cyclic bending with a 4 mm bending radius.
Developing a successful strategy to fabricate multifunctional sensors with high linear sensitivity is crucial for enhancing tactile interactions of the human body with the surrounding environment. Here, a stretchable multifunctional sensor consisting of stretchable porous film with multiscale aligned pores and Ag nanomesh electrode is reported. Due to the gradient in pore size and porosity inside the film, the sensor can detect bending and pressure simultaneously and independently as well as bending direction with quite high linear sensitivity up to 2 kPa. The 12 sensors are attached onto the tip and two joints each of four human fingers of one hand, and the capacitance changes measured by grabbing two different balls provide exact information associated with various hand gestures.
Ternary CuZrTi metallic glass thin films synthesized by sputtering are suggested as highly flexible and corrosion-resistant encapsulation materials. Unlike nanocrystalline Cu and binary CuZr metallic glass thin films, the ternary CuZrTi metallic glass thin films retain amorphous structure and do not oxidize even after 1000 h in an accelerated harsh environment at 85 °C with 85% relative humidity. The encapsulation performance of 260 nm thick ternary CuZrTi metallic glass is maintained even after 1000 bending cycles at a 3% tensile strain, corresponding to 70% of the elastic deformation limit, according to the results of a uniaxial tensile test. Because of the enhanced mechanical flexibility and reliability of the ternary CuZrTi metallic glass thin films, they have been applied to flexible organic solar cells as an encapsulation material.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.