Germany-based in-situ metrology system maker LayTec has announced that its new InspiRe system applies high-speed in-situ reflectance measurements for monitoring perovskite thin-film formations during spin-coating and subsequent annealing.

In collaboration with professor Norbert Nickel’s group at HZB, LayTec designed the InspiRe in-situ metrology system, which was applied to monitor both spin-coating and annealing. Gathering data at a time resolution on the millisecond scale allows resolving of the kinetics and phase formations during film formation.

An international research team has developed a new type of solar cell that can both withstand environmental hazards and is 26.7% efficient in power conversion.

Structure and photovoltaic performance for the perovskite-Si tandem device. Image by KAIST

The researchers, led by Byungha Shin, a professor from the Department of Materials Science and Engineering at KAIST, focused on developing a new class of light-absorbing material, called a wide bandgap perovskite. The material has a highly effective crystal structure that can process the power needs, but it can become problematic when exposed to environmental hazards, such as moisture. Researchers have made some progress increasing the efficiency of solar cells based on perovskite, but the material reportedly has greater potential than what was previously achieved.

The aging process of the perovskite solution used to fabricate solar cells makes the solution unstable, leading to poor efficiency and poor reproducibility of the devices. Reactants and preparation conditions also contribute to poor quality. To tackle these issues, a research team from the Qingdao Institute of Bioenergy and Bioprocess Technology (QIBEBT) of the Chinese Academy of Sciences (CAS) has studied the aging process of perovskite solution and proposed a way to avoid side reactions.

Prof. PANG Shuping, corresponding author of the paper, said "an in-depth understanding of fundamental solution chemistry had not kept up with rapid efficiency improvements in perovskite solar cells, even though such cells have been studied for 10 years... Normally, we need high temperature and a long time to fully dissolve the reactants, but some side reactions can happen simultaneously," said Prof. PANG. "Fortunately, we have found a way to inhibit them."