Tuning the Catalytic and Optical Properties of Designable Metal Nanoframes.

Metal nanoframes (MNFs) have received significant attention in various fields, particularly in energy and biomedical fields. The rapid increase in energy consumption in modern societies and the need for improved sensing devices have instigated researchers to explore various classes of materials. Nanoframes (NFs) particularly possess catalytic and optical properties, owing to their metallic composition and hollow structure compared to solid nanomaterials. Their physicochemical properties can be exploited to catalyze reactions for energy generation or tuned to enhance plasmonic properties such as localized surface plasmon resonance (LSPR) and surface-enhanced Raman spectroscopy (SERS) for sensing or imaging applications. Considerable improvements in design and synthetic protocols have been achieved to optimize material utility. In this review, we comprehensively discuss the prominence of MNFs as catalysts and sensors, enabling future renewable energy alternatives and hotspot-equipped nanomaterials. We discuss various strategies adopted to control the morphology of the NF. We subsequently enumerate notable examples of their catalytic and optical applications. Finally, we summarize the advances achieved and highlight the understanding and requirements to effectively overcome the persisting challenges in the design and synthesis protocol of NFs.