X-ray photoelectron spectroscopy for characterization of bionanocomposite functional materials for energy-harvesting...

The analysis of hybrid multicomponent bioorganic and bioinorganic composite materials related to energy technologies by using X-ray photoelectron spectroscopy is discussed. The approaches and considerations of overcoming the difficulties of analyzing hybrid multicomponent materials are demonstrated for different types of materials used in bioenzyme fuel cells, that is, enzyme immobilization in a hybrid inorganic-organic matrix, analysis of peptide binding and structure in the mediation of silica nanoparticle formation, analysis of enzyme-polymeric multilayered architectures obtained through layer-by-layer assembly, and study of the mechanism of electropolymerization. Thorough optimization of experimental design through analysis of an adequate set of reference materials, relevant timescales of sample preparation and X-ray exposure, careful peak decomposition and cross-correlation between elemental speciation, results in a detailed understanding of the chemistry of nanocomposite constituents and interactions between them. The methodology presented and examples discussed are of significant importance to the scientific and engineering communities focused on the immobilization of enzymes, proteins, peptides, and other large biological molecules on solid substrates.