Major hurdle in photovoltaic technologies surpassed with use of hydrazide indole additive

Harnessing solar energy to produce usable power is not new, but the technology is constantly evolving and improving. A major development in recent times is the use of perovskite solar cells (PSCs), which are low-weight, highly efficient, flexible solar cells using perovskite (typically a metal-halide material with a specialized structure) crystal structures to absorb light. Though a promising concept, improvements are necessary for PSCs to be able to reach their full potential. Researchers approach these improvements by introducing an additive, 1H-indole-3-carbohydrazide (1H-CBH) to effectively alleviate the main obstacle of PSCs, which are defects leading to loss of energy and efficiency in the cell.

Results were published in Energy Materials and Devices in March of 2026.

PSCs boast some impressive attributes, but getting past “defect-induced nonradiative recombination” has been an issue since its rapid rise in the scientific limelight. Defect-induced nonradiative recombination can be simply stated as an undesired loss of energy caused by defects in the materials used, where the energy is lost in the form of heat instead of light, as desired. This reduces the efficiency and stability when operated, which is undesirable for nearly any type of technology, especially those that are intended to have a certain amount of longevity and performance throughout the life of the object.

Researchers found the use of 1H-CBH, a multifunctional molecular additive, solves the issue through defect passivation, which is the process of removing or reducing surface defects in materials. This passivation leads to improvements across the board in stability and power conversion efficiency (PCE). In a series of three steps, this mechanism can reduce the reactivity of the metals used, in turn making the unit more corrosion-resistant, as well as creating the necessary bonds within the PSCs to mitigate the root problem of nonradiative recombination, which leads to an inappropriate form of energy loss.

“The multi-passivation strategy effectively mitigates ion migration, phase segregation, and

crystallinity degradation, thereby enhancing both the photovoltaic efficiency and operational stability of the resulting devices. By incorporating 1H-CBH, we achieve a critical balance between high performance and long-term durability, advancing the commercial viability of

perovskite solar technology,” said author Chengcheng Wu of Tsinghua University.

The results speak kindly of the work of the researchers, with enhanced PCE from 21.18% to 23.58%, retention of more than 80% of the cell’s initial PCE after 600 hours of continuous storage and no loss of shape after eight months of storage under ambient conditions. These promising results are not all: larger grains within the cell are produced, which reduces defects and leads to increased compatibility with the electron-transport layer, ultimately making the solar cell more efficient and stable.

Working with the information gleaned in this study, the researchers hope to achieve reliable and scalable photovoltaic technology in the form of these highly efficient and durable PSCs. Making this technology scalable, along with the low-cost, would allow for a wider application of use and its ease in fabrication further lends to its potential to be a leading force in the world’s reliable photovoltaic technologies.

Zhuo Peng, Han Wang, Jiazhi Meng, Xin Hong, Wenqiang Ding, Jianghao Yin, Chengcheng Wu, Guodan Wei and Feiyu Kang of the Institute of Materials Science, Tsinghua Shenzhen International Graduate School at Tsinghua University, Kefei Shi of the Department of Materials Science and Engineering at the University of Illinois and Na Liu, Faculty of Materials Science at MSU-BIT University contributed to this research.

The National Natural Science Foundation of China, the Shenzhen Distinguished Talent Program and the Tsinghua Shenzhen International Graduate School Overseas Research Cooperation Fund supported this research.