@article{Zhao2021, 
author = {Xuewei Zhao and Yizeng Wu and Zhiyuan Xia and Shulong Chang and Yuanyuan Shang and Anyuan Cao},
title = {A GQD-based composite film as photon down-converter in CNT/Si solar cells},
year = {2021},
journal = {Nano Research},
volume = {14},
number = {11},
pages = {3893-3899},
keywords = {graphene quantum dots, polyvinyl pyrrolidone, energy-down-shift, external quantum efficiency, CNT/Si solar cells},
url = {https://www.sciopen.com/article/10.1007/s12274-021-3311-5},
doi = {10.1007/s12274-021-3311-5},
abstract = {Graphene quantum dots (GQDs), have unique quantum confinement effects, tunable bandgap and luminescence property, with a wide range of potential applications such as optoelectronic and biomedical areas. However, GQDs usually have a strong tendency toward aggregation especially in making solid films, which will degrade their optoelectronic properties, for example, causing undesired fluorescence quenching. Here, we designed a composite film by embedding GQDs in a polyvinyl pyrrolidone (PVP) matrix through hydrogen bonding with well-preserved fluorescence, with a small addition of acid for compensating the poor conductivity of PVP. As a multifunctional solid coating on carbon nanotube/silicon (CNT/Si) solar cells, the photon down-conversion by GQDs and the PVP anti-reflection layer for visible light lead to enhanced external quantum efficiency (by 12.34% in the ultraviolet (UV) range) and cell efficiency (up to 14.94%). Such advanced optical managing enabled by low-cost, carbon-based quantum dots, as demonstrated in our results, can be applied to more versatile optoelectronic and photovoltaic devices based on perovskites, organic and other materials.}
}