Optical-electrical synergistic optimization of FEP/Al2O3 anti-reflective coating for solar cells

: This paper introduces a double-layer anti-reflective coating composed of ethylene propylene fluoride (FEP) and alumina (Al 2 O 3 ), capitalizing on the superior optical and chemical properties of FEP, including its low refractive index, exceptional chemical inertness, and weatherability. This structure possesses ideal characteristics for serving as the functional surface of photovoltaic modules, which are fabricated sequentially via magnetron sputtering followed by ultrasonic spray deposition. In the coating structure design, with optoelectronic synergy as the guiding principle, electrical requirements are proactively incorporated upfront into the optimization of coating parameters. By combining the equivalent interface theory with the quarter-wavelength principle, the simplex optimization algorithm is utilized. Experimental validated optical model by TFCalc confirms that this coating structure achieves a weighted average reflectance of merely 1.26% within the 400-1100 nm spectral range. The design enables the reflectance to consistently maintain below 1.1% across the incident angle of 0°-55°. The thickness of coating with low refractive index exhibits greater effects to reflectance, especially for the double-layer structure with a 157% fluctuation. An electrical model developed by PC1D software employing dual-diode model demonstrates a significant enhancement in photovoltaic conversion efficiency compared to uncoated glass. Furthermore, a comprehensive year-round simulation model has been established to integrate inclined-surface irradiation, energy yield, economic analysis, and carbon emission assessment. Model projection reveals that, the FEP/Al 2 O 3 structure achieves annual energy yield gain of 2,431.85 kWh and carbon emission reduction of 1,510.18 kg relative to uncoated system.