Vanadium Oxide as Transparent Carrier-Selective Layer in Silicon Hybrid Solar Cells Promoting Photovoltaic Performances

Abstract

Vanadium pentoxide (V2O5) has been proposed as a promising selective contact for holes in organic electronic devices. In this study, the strategy was undertaken for minimizing the possible charge recombination at electrode surfaces in the silicon-based hybrid solar cells and further allowed the exceptional capability for hole extraction. This was accomplished by inserting the mixed vanadium oxide (VOx) phases based on a simplified low-temperature fabrication process. Detailed examinations of crystallinity, chemical states and compositions, topography, and optical transmittance of such VOx layer were performed, revealing the coexistence of V2O3 and V2O5 phases that facilitated the hole-selective contact due to establishing the ohmic-like interfaces as well as blocking the transport of electrons, and the optimal anneal treatment at 200 °C was further validated. On the basis of this, the insertion of a VOx electron-blocking layer in the integrated organic/inorganic hybrid solar cells was fully fabricated with solution processing methods, presenting the leading conversion efficiency of 14.4% being approximately 1.6 times superior than the conventional VOx-free hybrid solar cells. These results provided a viable rule toward realizing the high-performance and low-cost solar cells and might further offer the high potential for other functional applications based on hybrid material designs.