Nanoporous Anodic Alumina Photonic Crystals for Sunlight Harvesting Applications: A Perspective

Nanoporous anodic alumina (NAA) fabricated by anodization of aluminum is a versatile platform material with tailorable geometric, optical, and chemical features for specific light-based technologies and applications. Recent advances in anodization technology have enabled a new generation of NAA-based photonic crystals (PCs)-periodic dielectric nanoporous structures that selectively allow, forbid, and confine the flow of incoming electromagnetic waves of specific wavelengths across their structure. NAA-PCs provide exciting new opportunities to engineer light-matter interactions with versatility across the broad spectrum, from UV to IR. But despite these fundamental advances, demonstrations of sunlight-harvesting technologies based on NAA-PCs are still limited. Herein, an up-to-date summary of recent advances in NAA-PC technology is provided, and proof-of-concept demonstrations and future pathways to propel this versatile platform material across sunlight-harvesting technologies such as photocatalysis, photoelectrocatalysis, photothermal energy conversion, and solar cells are discussed.