A special molecule helps control how perovskite forms, boosting solar cell efficiency and stability.
Scientists have developed a new way to significantly improve the performance of tandem solar cells by introducing a special molecule during manufacturing. This breakthrough has enabled researchers at the National University of Singapore, in collaboration with industry partners, to achieve a power conversion efficiency of 32.76 percent, one of the highest recorded for this type of solar technology.
Solar energy already plays a key role in generating electricity without carbon emissions, but conventional solar panels typically convert only about 25 percent of incoming sunlight into usable energy. To move closer to a clean energy future, improving this efficiency is essential. This is where perovskites, a class of materials known for their excellent light-absorbing properties, offer great potential. They are also relatively low-cost compared to traditional silicon. However, perovskites are highly sensitive to environmental factors such as heat, moisture, and light, which has limited their large-scale application.
To address these challenges, scientists have been developing tandem solar cells, which combine a perovskite layer with a silicon layer. This design allows better utilization of sunlight, but stability issues remain. During manufacturing, heat from silicon layers can cause the perovskite to crystallize too quickly, leading to defects and reduced durability.
The research team tackled this problem by introducing a molecule called 2-mercaptobenzothiazole. This molecule interacts with the organic components of the perovskite in a unique dual-binding manner, helping to control how the material crystallizes. By slowing down this process, the researchers were able to produce smoother, more uniform films with fewer defects.
As a result, the prototype tandem solar cells not only achieved a certified efficiency of 32.76 percent but also demonstrated strong durability, retaining 91 percent of their original performance after 1,700 hours of continuous operation.
This advancement represents a major step toward making high-efficiency, stable tandem solar cells commercially viable. The researchers believe their method can be scaled up for industrial production, potentially accelerating the global transition to cleaner and more efficient solar energy technologies.
