Ultraflexible And Lightweight Bamboo-derived Transparent Electrodes For Perovskite Solar Cells

Flexible wearable devices provide convenience for our life,and flexible transparent substrate is an essential part of it.Wearable devices are mainly based on plastic substrates,such as polyethylene terephthalate and polyethylene naphthalate,which will cause environmental pollution after use due to the long decomposition periods.Herein,it is necessary to prepare an environmentally friendly biodegradable transparent conductive substrate.In this paper,we report on the fabrication of a biodegradable and biocompatible transparent conductive electrode derived from bamboo,which is sputtered by IZO materials.The bamboo-derived cellulose nanofibrils electrode exhibits excellent transparency.The bio-substrate presents an optical transmittance over 90%in the visible wavelength range.The conductive bio-electrode exhibits extremely flexible properties.After bending 3000 times with a curvature radius of 4 mm or even undergoing a crumpling test,it still shows excellent electrical performance and negligible decay.Moreover,we apply the transparent cellulose nanofiber electrode to perovskite solar cells.The performance of the bamboo-based bio-electrode perovskite solar cell shows a record power conversion efficiency of 11.68%,which is the highest efficiency reported for a perovskite solar cells based on a biomass electrode.It is worth noting that the flexible device has a highly bendable mechanical stability,maintaining over 70%of its initial efficiency after bending 1000 times at curvature radius of 4 mm.This work paves the way for perovskite solar cells toward comfortable and environmentally friendly wearable devices.