An Absorption-Transport Reconfigurable 2D/3D/2D Architecture Enables Multispectral-Adaptive Bifacial Perovskite Photovoltaics.

Abstract

Tandem architectures have emerged as the prevailing strategy to overcome the fundamental trade-off between broadband photon absorption and efficient photon-energy utilization in photovoltaic devices. However, only the complex and implementation-demanding multi-terminal tandem configuration offers adaptability to diverse light sources. Here, we introduce an absorption-transport reconfigurable architecture implemented in a bifacial single-junction device, which harnesses the previously overlooked parasitic absorption of a 2D perovskite passivation layer to achieve spectral absorption separation between high-energy blue-violet and low-energy green-to-near-infrared photons. This design not only enables efficient bifacial operation with near-omnidirectional light harvesting but also supports broadly applicable photon-energy harvesting under both sunlight and artificial lighting. Notably, the V_oc under blue-light illumination reaches 1.67 V, exceeding the V_oc ceiling of a 1.55 eV single-junction absorber. In terms of applicability, a single device can deliver PCEs of 24.69% (AM 1.5G), 38.45% (warm-white LED), and 37.55% (cool-white TL84 fluorescent), alongside a record V_oc of 1.081 V under weak illumination (1122 lux/346 µW cm^-2). Owing to the robust interfacial anchoring design, the champion device retains >90% of its initial performance after 2000 h of continuous operation, thereby offering a viable pathway toward rapid, scenario-agnostic deployment.