Transparent solar cells(TSCs)are emerging devices that combine the advantages of visible transparency and light-toelectricity conversion.Currently,existing TSCs are based predominantly on organics,dyes,and perovskites...Transparent solar cells(TSCs)are emerging devices that combine the advantages of visible transparency and light-toelectricity conversion.Currently,existing TSCs are based predominantly on organics,dyes,and perovskites;however,the rigidity and color-tinted transparent nature of those devices strongly limit the utility of the resulting TSCs for realworld applications.Here,we demonstrate a flexible,color-neutral,and high-efficiency TSC based on a freestanding form of n-silicon microwires(SiMWs).Flat-tip SiMWs with controllable spacing are fabricated via deep-reactive ion etching and embedded in a freestanding transparent polymer matrix.The light transmittance can be tuned from ~10 to 55% by adjusting the spacing between the microwires.For TSCs,a heterojunction is formed with a p-type polymer in the top portion of the n-type flat-tip SiMWs.Ohmic contact with an indium-doped ZnO film occurs at the bottom,and the side surface has an Al2O3 passivation layer.Furthermore,slanted-tip SiMWs are developed by a novel solventassisted wet etching method to manipulate light absorption.Finite-difference time-domain simulation revealed that the reflected light from slanted-tip SiMWs helps light-matter interactions in adjacent microwires.The TSC based on the slanted-tip SiMWs demonstrates 8%efficiency at a visible transparency of 10% with flexibility.This efficiency is the highest among Si-based TSCs and comparable with that of state-of-the-art neutral-color TSCs based on organic–inorganic hybrid perovskite and organics.Moreover,unlike others,the stretchable and transparent platform in this study is promising for future TSCs.展开更多
基金supported by Mid-career Researcher Program through the National Research Foundation of Korea(NRF)grant funded by the Korea government(NRF-2018R1A2B2003720).
文摘Transparent solar cells(TSCs)are emerging devices that combine the advantages of visible transparency and light-toelectricity conversion.Currently,existing TSCs are based predominantly on organics,dyes,and perovskites;however,the rigidity and color-tinted transparent nature of those devices strongly limit the utility of the resulting TSCs for realworld applications.Here,we demonstrate a flexible,color-neutral,and high-efficiency TSC based on a freestanding form of n-silicon microwires(SiMWs).Flat-tip SiMWs with controllable spacing are fabricated via deep-reactive ion etching and embedded in a freestanding transparent polymer matrix.The light transmittance can be tuned from ~10 to 55% by adjusting the spacing between the microwires.For TSCs,a heterojunction is formed with a p-type polymer in the top portion of the n-type flat-tip SiMWs.Ohmic contact with an indium-doped ZnO film occurs at the bottom,and the side surface has an Al2O3 passivation layer.Furthermore,slanted-tip SiMWs are developed by a novel solventassisted wet etching method to manipulate light absorption.Finite-difference time-domain simulation revealed that the reflected light from slanted-tip SiMWs helps light-matter interactions in adjacent microwires.The TSC based on the slanted-tip SiMWs demonstrates 8%efficiency at a visible transparency of 10% with flexibility.This efficiency is the highest among Si-based TSCs and comparable with that of state-of-the-art neutral-color TSCs based on organic–inorganic hybrid perovskite and organics.Moreover,unlike others,the stretchable and transparent platform in this study is promising for future TSCs.
