Bombyx mori silk/titania/gold hybrid materials for photocatalytic water splitting: combining renewable raw materials with clean fuels

Abstract

The synthesis, structure, and photocatalytic water splitting performance of two new titania (TiO2)/gold(Au)/Bombyx mori silk hybrid materials are reported. All materials are monoliths with diameters of up to ca. 4.5 cm. The materials are macroscopically homogeneous and porous with surface areas between 170 and 210 m2/g. The diameter of the TiO2 nanoparticles (NPs) – mainly anatase with a minor fraction of brookite – and the Au NPs are on the order of 5 and 7–18 nm, respectively. Addition of poly(ethylene oxide) to the reaction mixture enables pore size tuning, thus providing access to different materials with different photocatalytic activities. Water splitting experiments using a sunlight simulator and a Xe lamp show that the new hybrid materials are effective water splitting catalysts and produce up to 30 mmol of hydrogen per 24 h. Overall the article demonstrates that the combination of a renewable and robust scaffold such as B. mori silk with a photoactive material provides a promising approach to new monolithic photocatalysts that can easily be recycled and show great potential for application in lightweight devices for green fuel production.

Ionic Liquid-Assisted Synthesis of Mesoporous Silk Fibroin/Silica Hybrids for Biomedical Applications

“…However, because of its availability, Bombyx mori (silkworm) silk is the most widely investigated type of silk . Overall, silk has been extensively explored in various fields, but most of the research has been directed toward innovative applications in biomedical systems for drug delivery, enzyme immobilization, wound dressing, adhesive fillers, and tissue engineering. , More recently, the use of silk in sustainable bio-inspired devices has raised considerable attention ,− and applications of silk-based materials in optics, − photonics, electronics, ,− smart windows, and energy storage/conversion ,− have emerged. Because of its outstanding mechanical properties, good biocompatibility, controlled biodegradability, − and ease of processing into a wide variety of shapes (e.g., films, nanofibers, gels, hydrogels, scaffolds, micro- and nano-particles), silk has also been proposed as scaffold for bone tissue regeneration. − Silk has, however, two major drawbacks that limit its application in the field of biomaterials: − (1) it does not exhibit any osteoinductivity and (2) it has a nonideal osteoconductivity.…”