Deoxyribonucleic acid-based electron selective contact for crystalline silicon solar cells

Abstract

Development of carrier selective contacts for crystalline silicon solar cells has been recently of great interest towards the further expansion of silicon photovoltaics. The use of new electron and hole selective layers has opened an array of possibilities due to the low-cost processing and non-doping contacts. Here, a non-doped heterojunction silicon solar cell without the use of any intrinsic amorphous silicon is fabricated using Deoxyribonucleic acid (DNA) as the electron transport layer (ETL) and transition metal V₂O₅ as the hole transport layer (HTL). The deposition and characterization of the DNA films on crystalline silicon have been studied, the films have shown a n -type behaviour with a work function of 3.42 eV and a contact resistance of 28 mΩ cm². This non-doped architecture has demonstrated a power conversion efficiency of 15.5%, which supposes an increase of more than 9% with respect to the cell not containing the biomolecule, thus paving the way for a future role of nucleic acids as ETLs.