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Methacrylate-labeled SBA-15 has been successfully synthesized from calcined SBA-15 and commercially available 3-trichlorosilyl propylmethacrylate. This material undergoes efficient thiol–ene “click reaction” with a variety of both thiol and disulfide-containing substrates in aqueous and organic media. The products were thoroughly characterized by a variety of analytical techniques including multinuclear (13C, 29Si) solid-state NMR, TG-DTA, and nitrogen adsorption desorption studies. Disulfide-containing substrates in which the TCEP-mediated reduction of the disulfide bond and its subsequent addition to the methacrylate group anchored in SBA-15 in one-pot were used to synthesize a silica–protein hybrid material composed of biotin-labeled SBA-15 and streptavidin. Electrochemically active material was synthesized from the reaction of ferrocene-containing thiol and the methacrylate-labeled SBA-15. The ease of synthesis for the methacrylate-labeled SBA-15 material together with its ability to undergo efficient chemoselective thiol–ene reaction would make it a very attractive platform for the development of covalently anchored enzymes and sensors.

Assembly of nanoparticles into free-standing threedimensional networks has implications for a wide range of applications. We show that dynamic templating of surfactant hexagonal domains is a facile technique to organize nanoparticles into a network of particulate strands. Dispersed particles (>10 nm), independent of particle chemistry, assemble into networks, when the surfactant matrix cools into the hexagonal phase. We demonstrate assembly of inorganic, polymeric, and protein nanoparticles into networks. Where particle assembly is reversible, particles are coated with polymers that are subsequently cross-linked to stabilize the networks after surfactant removal. This technique involves near ambient temperatures and a benign water wash for template removal. The network mesh size can be varied from submicrometers to tens of micrometers by controlling the cooling rate. Particle networks can be flow-oriented prior to cross-linking, and interpenetrating networks can also be formed.

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Metal–semiconductor hybrids are a promising architecture for functional nanostructures because they efficiently promote charge separation. The morphology of the hybrid supports two mechanisms of charge generation and transfer, namely, the excitation of electrons to the conduction band of the semiconductor or the induction of surface plasmon resonance on the metal. Here, we compared the photocatalytic activity of nanoparticles with a core–shell or dimer morphology, using Pt, Pd, or Au as the metal and Cu2ZnSnS4 (CZTS), which comprises abundant and environmentally friendly elements, as the semiconductor. Their performance as photocatalysts was evaluated by using Methylene Blue (MB) degradation under light irradiation. We found that although large Au cores improved the photocatalytic activity of the CZTS nanoparticles, the highest catalytic activity was that of Pt–CZTS and Pd–CZTS dimers. Conversely, using small metal particles as cores degraded the activity of the CZTS due to the formation of an internal boundary and the occupation of potentially optically active volume. In addition, the results point out that depositing multiple metal particles is not beneficial for photocatalysis.