Dipole engineering in self-assembled monolayers for efficient organic–silicon hybrid solar cells
Abstract
Organic–silicon hybrid solar cells, as dopant-free heterojunction devices, hold significant potential for achieving high performance-to-cost ratios in photovoltaics. Critical to their advancement is the engineering of carrier-selective contacts that minimize interfacial losses. Here, we demonstrate a carbazole-based self-assembled monolayer (SAM), [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid (Me-4PACz), as an efficient electron-selective layer in [poly(3,4 ethylenedi oxythiophene):polystyrene sulfonate (PEDOT:PSS)]/Si solar cells. The Me-4PACz SAM introduces a directional dipole moment at the c-Si/Al interface, generating a built-in electric field that enhances electron extraction. This interface modification leads to a linear Ohmic contact, reducing the contact resistivity between n-Si and the metal electrode interface to 4.12 mΩ cm2. Consequently, the optimized device achieves a power conversion efficiency (PCE) of 16.75% with a high open-circuit voltage (VOC) of 651 mV and fill factor of 78.03%, representing a ∼14% relative PCE improvement over the control device (PCE = 14.75%). Our work provides a molecular-scale strategy for tailoring carrier dynamics in silicon-based heterojunctions, offering a pathway toward low-cost, high-efficiency photovoltaic technologies.
Article Details
Journal Info
Applied Physics Letters
American Institute of Physics
Authors (6)
Zhangbo Lu
Key Laboratory of Solid State Optoelectronic Devices of Zhejiang Province, College of Physics and Electronic Information Engineering, Zhejiang Normal University , Jinhua 321004,
Jiahui Chen
Yueyue Wu
Key Laboratory of Solid State Optoelectronic Devices of Zhejiang Province, College of Physics and Electronic Information Engineering, Zhejiang Normal University , Jinhua 321004,
Huanyu Wen
Key Laboratory of Solid State Optoelectronic Devices of Zhejiang Province, College of Physics and Electronic Information Engineering, Zhejiang Normal University , Jinhua 321004,
Dan Chi
Key Laboratory of Solid State Optoelectronic Devices of Zhejiang Province, College of Physics and Electronic Information Engineering, Zhejiang Normal University , Jinhua 321004,
Shihua Huang
Key Laboratory of Solid State Optoelectronic Devices of Zhejiang Province, College of Physics and Electronic Information Engineering, Zhejiang Normal University , Jinhua 321004,