Development of Flexible Near-Infrared Solar Cells

The research group led by Prof. XIONG Yujie at the University of Science and Technology of China has invented a new class of flexible near-infrared solar cells based on the plasmonic hot electron injection into silicon nanowire arrays. This work was published online in Angewandte Chemie International Edition (DOI: 10.1002/anie.201600279) on March 1, 2016.

Photovoltaic (PV) technologies that harvest and convert sunlight directly into electricity will play a vital role in efforts to provide clean and secure sources of energy. To fully utilize solar energy, the near-infrared (NIR) light which accounts for about 52% of solar photons should be harvested for electricity generation.

Given that most of the existing PV devices are designed for visible light utilization, it is a strong demand to develop NIR PV modules through device structure and mechanism innovation. In addition to NIR utilization, another major trend in PV development is to fabricate devices with lightweight and mechanical flexibility.

In this work, the research team has developed an approach to improve the quantum efficiency of flexible PV devices in NIR spectral region by integrating silicon nanowire arrays with plasmonic silver nanoplates. The silver nanoplates can directly harvest and convert NIR light into plasmonic hot electrons for injection into Si, while the Si nanowire arrays offer light trapping. Under the NIR light illumination, the external quantum efficiency has been improved by 59% with the integration Ag nanoplates. The concept has been demonstrated for two different types of PV devices, inorganic-organic hybrid cell and Schottky-type cell. This work provides an alternative strategy for the design and fabrication of flexible NIR PVs.

 

Flexible near-infrared solar cells based on plasmonic hot electron injection (Courtesy of XIONG Yujie and Angewandte Chemie International Edition)

This work was financially supported by the NSFC, the Specialized Research Fund for the Doctoral Program of Higher Education, the Recruitment Program of Global Experts, the CAS Hundred Talent Program, the Hefei Science Center CAS, and the Fundamental Research Funds for the Central Universities. This work was partially carried out at the USTC Center for Micro and Nanoscale Research and Fabrication.