Programmable 3D Photovoltaics via Mechanically Origami-Coded Interlocked 3D Kirigami and Nano-Root Anchored AgNWs-In-Ga Multiphasic Alloy Conductor.

Abstract

3D photovoltaics (3DPVs) are highly promising for next-generation energy systems, as they maximize space utilization and power output. However, most reported 3DPVs remain unsuitable for deformable applications. When 3DPVs are integrated with mechanically deformable platforms, a fundamental trade-off emerges: achieving large mechanical stretchability typically leads to a reduction in areal coverage. Here, we present a single-material, mechanically origami-coded 3D kirigami platform that enables programmable 3DPVs with unprecedented stretchability and areal coverage. Origami, which transforms 2D geometries into 3D forms, provides an effective structural strategy to overcome the long-standing trade-off between stretchability and areal coverage. Leveraging this concept, we introduce an origami-inspired mechanical coding scheme that embeds programmable folding behavior into the structure. A simple extension-release cycle drives unit folding initiation and full origami activation, achieving ultrahigh stretchability (500%) and initial effective areal coverage (225%), while maintaining stable photovoltaic output under extreme deformation and repeated cycling. To ensure reliable electrical integration, an intrinsically integrable nano-root anchored AgNWs-In-Ga multiphasic alloy conductor was co-fabricated with the structure, providing stable conductivity and enabling reversible stack-and-connect operation. This approach highlights geometric programmability as a key enabler for freeform photovoltaics, establishing a pathway toward multifunctional 3D energy systems for adaptive devices, and urban energy harvesting.