Thiolated Lysine‐Leucine Peptides Self‐Assemble into Biosilica Nucleation Pits on Gold Surfaces

Nanostructured silica architectures have led to many applications in electronic and optical devices, and catalysis. Recently, bioinspired approaches based on peptide‐assisted silica fabrication have attracted great attention because of low production cost and mild, sustainable fabrication methods. Herein it is demonstrated that biomimetic peptides can also exert control over silica mineralization when bounded to inorganic surfaces. The amphiphilic α‐helical peptide LKα14 (Ac‐LKKLLKLLKKLLKLC‐OH) is used, which is based on leucine and lysine and has been a model system for surface studies and mineralization in solution for several years. LKα14 has been anchored to gold surfaces via terminal cysteine groups as linkers. Using X‐ray photoelectron spectroscopy, vibrational sum frequency generation spectroscopy, scanning force microscopy, and molecular dynamic simulations, it is found that LKα14 peptides assemble into laterally ordered structures with ≈5 nm wide cavities which serve as effective nucleating sites for silica nanoparticles.