Self-Assembly of Metal and Metal Oxide Nanoparticles and Nanowires into a Macroscopic Ternary Aerogel Monolith with Tailored Photocatalytic Properties

Abstract

Self-assembly processes represent the most powerful strategy to produce complex materials with unique structural and compositional sophistication. Here we present such a self-assembly route to a three-component aerogel from preformed nanoparticle building blocks. Starting with a mixture of gold and anatase nanoparticles and tungsten oxide nanowires, controlled cogelation resulted in the formation of a macroscopic aerogel monolith with high specific surface area and porosity, remarkable transparency, and excellent crystallinity. The modular approach enables us to fine-tune the composition of the aerogels, and thus their properties, by choosing the appropriate building blocks and their relative concentration ratios. As an illustrative example, we show the targeted tailoring of the photocatalytic activity: the gold nanoparticles and the tungsten oxide nanowires both add their specific beneficial effects to the anatase aerogel matrix, leading to a superior performance of the three-component system