A biomimetic nickel bis-diphosphine complex incorporating the amino acid arginine in the outer coordination sphere was immobilized on modified carbon nanotubes (CNTs) through electrostatic interactions. The functionalized redox nanomaterial exhibits reversible electrocatalytic activity for the H /2 H interconversion from pH 0 to 9, with catalytic preference for H oxidation at all pH values. The high activity of the complex over a wide pH range allows us to integrate this bio-inspired nanomaterial either in an enzymatic fuel cell together with a multicopper oxidase at the cathode, or in a proton exchange membrane fuel cell (PEMFC) using Pt/C at the cathode. The Ni-based PEMFC reaches 14 mW cm , only six-times-less as compared to full-Pt conventional PEMFC. The Pt-free enzyme-based fuel cell delivers ≈2 mW cm , a new efficiency record for a hydrogen biofuel cell with base metal catalysts.

The oriented in situ crystallisation of microporous manganese(II) formate [Mn(HCO 2 ) 2 ] on different porous supports (e.g. porous alumina and graphite) has been investigated. The anisotropic growth of Mn(HCO 2 ) 2 was examined by Xray diffraction (XRD) and scanning electron microscopy (SEM). The intracrystalline diffusion of methanol in Mn(HCO 2 ) 2 was studied by observation of the sorption kinetics by interference microscopy (IFM). It was found that untreated discs of porous alumina and graphite supports exhibit poor densities of Mn(HCO 2 ) 2 crystals per supported area. Even lower crystal densities are found for activated supports such as for alumina after basic treatment and for oxidized graphite supports. Improved results have been achieved by replacing formic acid by sodium formate in the synthesis

The intracrystalline concentration profiles during molecular uptake of methanol by an initially empty, single crystal of microporous manganese(II) formate (Mn(HCO2)2), representing an ionic inorganic-organic hybrid within the MOF family, are monitored by interference microscopy. Within these profiles, a crystal section could be detected where over the total of its extension ( approximately 2 microm x 50 microm x 30 microm) molecular uptake ideally followed the pattern of one-dimensional diffusion. Analysis of the evolution of intracrystalline concentration in this section directly yields the permeability of the crystal surface and the intracrystalline diffusivity as a function of the concentration of the total range of 0