The platinum hexahalides have an octahedral arrangement of six halogen atoms bound to a Pt centre, thus having an octahedral shape that could prove to be useful in interpreting poor electron-density maps. In a detailed characterization, PtI6 chemically transformed to a square-planar PtI3 complex bound to the Nδ atom of His15 of HEWL was also observed, which was not observed for PtBr6 or PtCl6.

Abstract. Multi heavy atom cluster compounds like K 2 PtBr 6 offer a way forward to solve, de novo, unknown protein structures by powder diffraction involving dispersive (measured at two X-ray wavelengths) and isomorphous intensity differences as a complement to micro-crystallography or by using both approaches in combination. Towards this end, using the ESRF high resolution synchrotron X-ray powder diffraction beamline ID31, we have recorded high quality protein powder diffractograms at the platinum LIII and bromine K absorption edges, as well as reference wavelengths, for K 2 PtBr 6 bound to lysozyme. These experiments were conducted at 80K to protect the sample against X-radiation damage as much as possible and also to fix the K 2 PtBr 6 bound state, which seemed to show instability at room temperature. With multiple powder pattern analysis we extracted intensities and showed the PtBr 6 bound in lysozyme using 'omit electron density maps'. In addition the wavelength dispersive Fourier around the Br K edge shows up the bromine signal at PtBr 6 binding site 1 in one of the six samples tested. To better understand the chemical properties of this heavy atom compound we have elucidated the detailed binding behaviour using single crystal analyses with time-resolved freeze quenching after soak times of 10, 90 and 170 minutes. Whilst the quick soaking of 10 to 30 minutes, used at ESRF ID31 shows clear binding, there is increasing binding strength with increasing soak time. Thus, these time-resolved analytical chemistry results show that further heavy atom signal optimizations are possible. Prospects for extending our approach to the yet larger isomorphous and wavelength dispersive signal case of Ta 6 Br 12 bound to lysozyme are also described.

A proton-conducting coordination polymer of anionic one-dimensional (1D) chains of Zn phosphate and protonated imidazole with the formula of [Zn(HPO)(HPO)](ImH) has been used as a novel supercapacitor material in aqueous electrolytes. This material stores charges via a proton-hopping mechanism.

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Time-resolved Laue protein crystallography at the European Synchrotron Radiation Facility (ESRF) opened up the field of sub-nanosecond protein crystal structure analyses. There are a limited number of such time-resolved studies in the literature. Why is this? The X-ray laser now gives us femtosecond (fs) duration pulses, typically 10 fs up to ∼50 fs. Their use is attractive for the fastest time-resolved protein crystallography studies. It has been proposed that single molecules could even be studied with the advantage of being able to measure X-ray diffraction from a 'crystal lattice free' single molecule, with or without temporal resolved structural changes. This is altogether very challenging R&D. So as to assist this effort we have undertaken studies of metal clusters that bind to proteins, both 'fresh' and after repeated X-ray irradiation to assess their X-ray-photo-dynamics, namely Ta6Br12, K2PtI6 and K2PtBr6 bound to a test protein, hen egg white lysozyme. These metal complexes have the major advantage of being very recognisable shapes (pseudo spherical or octahedral) and thereby offer a start to (probably very difficult) single molecule electron density map interpretations, both static and dynamic. A further approach is to investigate the X-ray laser beam diffraction strength of a well scattering nano-cluster; an example from nature being the iron containing ferritin. Electron crystallography and single particle electron microscopy imaging offers alternatives to X-ray structural studies; our structural studies of crustacyanin, a 320 kDa protein carotenoid complex, can be extended either by electron based techniques or with the X-ray laser representing a fascinating range of options. General outlook remarks concerning X-ray, electron and neutron macromolecular crystallography as well as 'NMR crystallography' conclude the article.

Although lithium–sulfur batteries have high theoretical capacities (1675 mA h g−1), an irreversible charge/discharge process (shuttle effect) due to polysulfide and insulating lithium sulfide formation causes the death of battery cells.

Li-S batteries with a sulphur loading content of 5 mg/cm2 were produced at large-scale 18650 cylindrical cells. We have found that a key failure mode of cylindrical Li-S battery cells...

Graphene based materials have received great attention in energy storage applications such as supercapacitor because of their excellent in surface area, conductivity, and stability. However, their capacitance is limited by surface area in which the energy was stored via reversible ion adsorption at the electrode surface by electrochemical double layer capacitance (EDLC) mechanism. According to the previous studies, heteroatom doping results in a chemical activity changing and enhance electrochemical capacitance. In this work, we demonstrated the effect of boron-doped reduced graphene oxide on electrochemical performance. The electrochemical evaluation was performed in half-cell configuration in 1 M KOH using boron-doped reduced graphene oxide coated on FTO glass as working electrode. The boron-doped reduced graphene oxide shown the specific capacitance up to 370 F g−1 in 1 M KOH at 0.6 A cm-2. In addition, due to their photo active property, boron-doped reduced graphene oxide as an anode was coupled with NixCo3-xO4 as a cathode to investigate the performance of the asymmetric supercapacitor in dark and light conditions. This will be further explored for the development of the photo asymmetric supercapacitor application as a new sustainable energy storage device.