Tech Insights

The Power of Perovskite: From Lab to Market, the Latest Advances in Solar Cells

July 10, 2023 by Shannon Cuthrell

Three studies highlight advancements in perovskite solar cell materials, efficiency, and commercialization. Here’s a briefing. 

Perovskite solar cells (PSCs) are charting continued progress in research and development as scientists work to boost their efficiency and lower costs on the path toward widespread commercialization. 

 

A researcher works on perovskite solar cells

A researcher works on perovskite solar cells. Image used courtesy of the National University of Singapore

 

PSCs, thin-film devices featuring layers of materials, are a relatively new but increasingly attractive subset of the solar energy market. Ongoing laboratory testing has seen their conversion efficiency jump from 3.8% 14 years ago to more than 25% today for single-junction designs. Tandem (stacked) architectures, which combine perovskite and silicon cells, boost that efficiency to 33.2%—a record set by KAUST Solar Center researchers earlier this year. 

Three new studies reveal even more progress in this burgeoning market, demonstrating further improvements in performance, power conversion efficiency, and material costs. 

 

Measuring Perovskites’ Performance Under High Temps, Heavy Sunlight

Researchers from Florida State University published a study in the Journal of Physical Chemistry examining the effect of high temperatures and light degradation on perovskite-sensitized upconversion under real-world conditions. 

In upconversion, low-energy photons are converted to a photon with a higher energy output. The researchers wanted to see if they could reuse photons that wouldn’t be converted to electricity by storing energy from one photon until a second emerges, then combining the two photons into one high-energy light particle. To explore this further, they studied the environmental stressors of heat and light on the triplet generation process. 

They discovered that while the perovskite degrades when exposed to heat and sunlight, placing organic molecules on top of the upconversion device would prevent degradation and extend the life of the perovskite. 

The researchers emphasized the need for more research to overcome engineering challenges. Still, the study highlights the continued potential for integrating perovskite-sensitized upconversion devices into commercial solar photovoltaic (PV) devices

 

Record-Breaking Power Conversion Efficiency 

A National University of Singapore (NUS) team recently broke world records with a 24.35% power conversion efficiency in a PSC sized at 1 square centimeter (cm2), up from 23.7%. 

To land this achievement in their 1-cm2 cell, the researchers incorporated a novel interface material offering advantageous optical, electrical, and chemical properties to boost its efficiency and longevity, thus improving durability and performance. 

The work appeared in a recent listing of Solar Cell Efficiency Tables, which tracks the highest independently verified efficiencies of solar cells and modules. The edition was published in Progress in Photovoltaics in June. 

The researchers aim to scale the cells into modules by adjusting their dimensions. Hou Yi, an assistant professor of chemical and biomolecular engineering at NUS, stated that the insights from the study are a roadmap for developing stable and commercially viable PSCs for the transition to renewable energy. The team’s next goal is to deliver a cell with 25 years of operational stability

 

Low-Cost Alternatives to Gold/Silver Layers

While a thin layer of gold or silver improves PSC efficiency, the same could be achieved with a cheaper alternative developed by researchers from Northern Illinois University and the National Renewable Energy Laboratory. 

 

bilayer back electrode

An overview of the bilayer back electrode, offering a vacuum-free design with a power conversion efficiency of 21%. Image used courtesy of the authors (Creative Commons BY license)
 

In a paper published in ACS Energy Letters, the researchers focused on a nickel-doped natural graphite layer combined with a fusible alloy layer. The bilayer back electrode configuration can be laminated to thin films on the perovskite device. This vacuum-free approach avoids expensive fabrication methods and allows the cells to reach a power conversion efficiency of 21%. 

However, the authors stated that future research could boost the efficiency to compete with the 26% benchmark of precious metal-based perovskites.