ABSTRACT
Here, we report photonic nanostructures replicated from the adaxial epidermis of flower petals onto light-polymerized coatings using low-cost nanoimprint lithography at ambient temperature. These multifunctional nanocoatings are applied to confer enhanced light trapping, water repellence, and UV light and environmental moisture protection features in perovskite solar cells. The former feature helps attain a maximum power conversion efficiency of 24.61% (21.01% for the reference cell) without any additional device optimization. Added to these merits, the nanocoatings also enable stable operation under AM 1.5G and UV light continuous illumination or in real-world conditions. Our engineering approach provides a simple way to produce multifunctional nanocoatings optimized by nature's wisdom.
ABSTRACT
We demonstrate that polyaniline (PANI) behaves as an anode buffer layer, which makes it an excellent hole transport layer. PANI was coated between the photoactive layer and the top anode in transparent flexible organic solar cells (OSCs). The performances of the devices with different PANI thicknesses were investigated. The results demonstrate that the power conversion efficiency (PCE) increased nearly four-fold with an 18 nm thick PANI layer compared to the reference cell without PANI. The optimum device performance with an 18 nm PANI layer exhibits a Jsc of 11.60 mA cm(-2), a V(oc) of 0.89 V, a FF of 66.87%, and thus a PCE of 6.87% under AM1.5G illumination of 100 mW cm(-2). The conversion efficiency of transparent flexible OSCs changes after 1500 bending cycles.
