High Weight-Specific Power Density of Thin-Film Amorphous Silicon Solar Cells on Graphene Papers

Chi Zhang,Min Yin,Xin Zhang,Linfeng Lu,Jinrong Cheng,Guqiao Ding,Peng Wang,Dongdong Li,Liyou Yang,Shuangying Cao

doi:10.1186/s11671-019-3132-6

Abstract

Flexible thin-film solar cells with high weight-specific power density are highly desired in the emerging portable/wearable electronic devices, solar-powered vehicles, etc. The conventional flexible metallic or plastic substrates are encountered either overweight or thermal and mechanical mismatch with deposited films. In this work, we proposed a novel substrate for flexible solar cells based on graphene paper, which possesses the advantages of being lightweight and having a high-temperature tolerance and high mechanical flexibility. Thin-film amorphous silicon (a-Si:H) solar cells were constructed on such graphene paper, whose power density is 4.5 times higher than that on plastic polyimide substrates. In addition, the a-Si:H solar cells present notable flexibility whose power conversion efficiencies show little degradation when the solar cells are bent to a radius as small as 14 mm for more than 100 times. The application of this unique flexible substrate can be extended to CuInGaSe and CdTe solar cells and other thin-film devices requiring high-temperature processing.

Highlights

Flexible and lightweight thin-film solar cells can be attached to objects with curved surfaces, making them suitable as a source of electricity supply units for portable/wearable electronic devices and unmanned aerial vehicles [1–5]
We demonstrated flexible thin-film amorphous silicon (a-Si: H) solar cells on smooth graphene papers which were achieved by a filtration method using porous anodic aluminum oxide (AAO) filter
By extending the etching time to 20 min, the barrier oxide layer will be completely removed, resulting in 100 nm in diameter holes, same as the front side. This AAO through-holes membrane with 20-min etching time is used for the filtration of graphene solution

Summary

Introduction

Flexible and lightweight thin-film solar cells can be attached to objects with curved surfaces, making them suitable as a source of electricity supply units for portable/wearable electronic devices and unmanned aerial vehicles [1–5]. Flexible solar cells can be realized by depositing absorbing layers together with other functional layers onto foreign substrates such as metallic [7–10] or plastic foils [11–14]. Researchers have proposed a method that epitaxially grows high-quality materials and transfers them onto foreign substrates using single-layer graphene [35]. This transfer technology requires careful handling and complex processes, which is timeconsuming and not compatible with large-scale production strategies

Methods

Results

Conclusion