Surface Density-of-States Engineering of Anatase TiO2 by Small Polyols for Enhanced Visible-Light Photocurrent Generation

Enhancement of visible-light photocurrent generation by sol-gel anatase TiO2 films was achieved by binding small polyol molecules to the TiO2 surface. Binding ethylene glycol onto the surface, enhancement factors up to 2.8 were found in visible-light photocurrent generation experiments. Density functional theory calculations identified midgap energy states that emerge as a result of the binding of a range of polyols to the TiO2 surface. The presence and energy of the midgap state is predicted to depend sensitively on the structure of the polyol, correlating well with the photocurrent generation results. Together, these results suggest a new, facile, and cost-effective route to precise surface band gap engineering of TiO2 toward visible-light-induced photocatalysis and energy storage

Palaeoproteomics of bird bones for taxonomic classification

Proteomic

Palaeoproteomics of fossil bird bones for taxonomic classification

We used proteomic profiling to taxonomically classify extinct, alongside extant bird species using mass spectrometry on ancient bone-derived collagen chains COL1A1 and COL1A2. Proteins of Holocene and Late Pleistocene-aged bones from dodo (Raphus cucullatus) and great auk (Pinguinus impennis), as well as bones from chicken (Gallus gallus), rock dove (Columba livia), zebra finch (Taeniopygia guttata) and peregrine falcon (Falco peregrinus), of various ages ranging from the present to 1455 years old were analysed. HCl and guandine-HCL-based protein extractions from fresh bone materials yielded up to 60% coverage of collagens COL1A1 and COL1A2, and extractions from ancient materials yielded up to 46% coverage of collagens COL1A1 and COL1A2. Data were retrieved from multiple peptide sequences obtained from different specimens and multiple extractions. Upon alignment, and in line with the latest evolutionary insights, protein data obtained from great auk grouped with data from a recently sequenced razorbill (Alca torda) genome. Similarly, protein data obtained from bones of dodo and modern rock dove grouped in a single clade. Lastly, protein data obtained from chicken bones, both from ancient and fresh materials, grouped as a separate, basal clade. Our proteomic analyses enabled taxonomic classification of all ancient bones, thereby complementing phylogenetics based on DNA