Hybrid Interconnecting Layers Boost Efficiency in Tandem Solar Cells

• Breakthrough tandem solar cell achieves record-breaking 28.47% efficiency with innovative hybrid interconnecting layers, setting new standards in renewable energy technology.

Researchers from China's Jinan University, University of Macau, Wuyi University, Guangdong Mellow Energy, and Germany's IEK-5 Photovoltaik have developed a two-terminal perovskite-silicon tandem solar cell with a record-breaking efficiency of 28.47%. The cell utilizes hybrid interconnecting layers to reduce recombination losses in the top perovskite device, achieving an impressive fill factor of 81.8%, the highest reported for this technology to date.

The hybrid interconnecting layers, based on sputtered nickel oxide (NiOx) as the seed layer of self-assembled monolayers (SAMs), prevent direct contact between the perovskite absorber and transparent conductive oxide (TCO). This approach improves the uniformity of the interface, reduces leakage current, and enhances carrier extraction and transportation, ultimately leading to the high efficiency of the tandem solar cell. The cell consists of a bottom silicon heterojunction device and a top inverted perovskite solar cell with various layers including a perovskite absorber doped with 2-phenylethylammonium iodide (PEAI) and an electron transport layer based on buckminsterfullerene (C60).

What innovative approach led to record-breaking efficiency in tandem solar cell development?

• Hybrid interconnecting layers utilizing sputtered nickel oxide (NiOx) as seed layer of self-assembled monolayers (SAMs)
  
• Prevention of direct contact between perovskite absorber and transparent conductive oxide (TCO)
  
• Improved interface uniformity, reduced leakage current, enhanced carrier extraction and transportation
  
• Bottom silicon heterojunction device paired with top inverted perovskite solar cell
  
• Perovskite absorber doped with 2-phenylethylammonium iodide (PEAI)
• Electron transport layer based on buckminsterfullerene (C60)