Researchers at MIT have developed a method to synthesize Spiro-MeOTAD, a crucial material for charge transport, without using noble metals. This development led to the creation of a solar cell with 24.2% efficiency, although it demonstrated rapid degradation.
The research team reported that the new method can produce a Spiro-MeOTAD material that remains stable even after 1,400 hours of testing at elevated temperatures (85°C) under continuous one-sun illumination. This durability is critical for materials exposed to the high temperatures and humidity typical of solar panel environments.
The recent study showed that even at low doping concentrations of 1%, Spiro units could increase their electrical conductivity by orders of magnitude.
One of the key benefits of the material is its high glass transition temperature, which is above 115°C. This allows the solar cell to exhibit enhanced thermal properties, making it more suitable for use in high-temperature environments.
While the thermally stable Spiro unit is only in a solar cell that reaches 6% efficiency, the research team expressed their vision for future research to stabilize the 24% efficiency solar cell.
According to the study, Spiro is currently an expensive material but the researchers predict that the price could drop significantly with bulk orders reaching kilogram levels.
