Gel‐Level Conversion: Customizing Silver‐Based Aerogels for Enhanced Electrocatalysis

Abstract As a well‐known coin metal, silver (Ag) stands out for its unique plasmonic properties and the lowest cost among all noble metals. However, the sol–gel chemistry of the Ag system remains undeciphered, challenging the rational design of Ag aerogels. Additionally, the chemical reactivity of Ag is often neglected in designing noble metal aerogels (NMAs), leaving significant potential untapped for advanced applications. Here, versatile engineering of Ag aerogels is realized by precisely tuning metal‐ion, metal‐ligand, and metal‐metal interactions, achieving a ligament size modulation across 3 orders of magnitude and downsizing the ligament size to <10 nm. The redox potential difference (Δ E )‐driven gel‐level conversion methodology is further established by utilizing the chemical activity of Ag and the self‐healing properties of noble metal hydrogels, stepwise yielding various self‐standing and hollow‐structured Ag‐M aerogels with record‐high performance for (photo)electrocatalysis. This study not only offers guidelines for manipulating multiscale structures of broad metal aerogels but also unveils their unprecedented potential for energy‐related applications.