A Scalable Polymer Multilayer Film Strategy for Colored Photovoltaics with Passive Thermal Management and Data-Driven Multiphysics Design

Building-integrated photovoltaics (BIPVs) are promising for sustainable urban energy systems but remain constrained by coupled trade-offs among aesthetics, power output, thermal management, and cost. Conventional pigment- or dye-based coloring often reduces power conversion efficiency (PCE) and durability, whereas many structurally colored photovoltaic strategies rely on complex, difficult-to-scale nanostructures. Here, we report a scalable colored photovoltaic strategy based on color-selective polymer multilayer films (PMF-C) derived from a PEN/PMMA platform compatible with continuous coextrusion and layer multiplication. PMF-C generates vivid structural coloration through a selective high-reflection stopband in the visible range while maintaining high transmission over the remaining photovoltaic-relevant spectrum. This spectral selectivity enables color generation and passive thermal regulation by reducing solar heat gain. Integrated with an infrared-emissive EVA encapsulation architecture, PMF-GPV achieves an operating-temperature reduction of up to ∼8.65 °C while retaining ∼74% of the baseline PCE. Beyond experimental demonstration, we establish a data-driven opto-thermo-electrical framework that predicts color, efficiency, and operating temperature prior to fabrication across a broad PMF-C material and structural design space. Parametric sweeps and Pareto analysis identify refractive-index combinations for efficiency-priority, temperature-priority, and balanced designs; notably, under an idealized uniform-thickness design, the PEN/PMMA pair is predicted to retain 86.9% of the reference-cell PCE while reducing the operating temperature by 5.17 K. A machine-learning-assisted inverse-design workflow rapidly maps target colors to feasible PMF-C structural parameters. This work provides both a scalable material platform and a predictive design framework for colored BIPVs with jointly engineered appearance, efficiency, and passive thermal-management performance.