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A real-time analysis by STA-FTIR of changes occurring and volatiles evolved during processing of perovskites for PV technology. Solvent retention, presence of chemical species and decomposition of materials can be evaluated to gain insight into material composition.

The phenomenology of zeolite collapse is outlined, drawing on recent synchrotron x-ray diffraction experiments and computer simulations of low density cage structures like zeolite A and zeolite Y. Attention is drawn to the importance of polyamorphism in destabilizing this type of microporous crystal and its role in order-disorder as well as amorphous-amorphous transitions, together with associated differences in entropy and density between polyamorphic phases and the precursor zeolite. Magic angle spinning NMR and inelastic x-ray scattering are used to highlight changes in structural order and mechanical rigidity between the starting zeolite and the final high density polyamorph. In conclusion, two-level systems detected with inelastic neutron scattering are described and their involvement in dictating the dynamics of the collapse of zeolitic cage structures.

We present a rapid (5 min) and controlled sensitisation method for dye sensitized solar cells which gives 6.0% for the Ru dye N719 and 3.7% for the IR absorbing squaraine SQ1. Rapid co-sensitization (N719 and SQ1) gives efficiencies up to 7.9%. Devices have similar or better efficiency to those dyed passively for 18 h.

This paper describes the synthesis of a new, yellow triphenylamine dye, 4-[2-(4-diphenylaminophenyl) vinyl]benzoic acid] (6), with a sorption maximum at 380 nm in solution for which EQE data show shifts to 420 nm on sorption to TiO 2 . The performance of this dye has been measured in dye-sensitized solar cell (DSC) devices, showing h ¼ 2.6% for 1 cm 2 devices. Light soaking of (6) shows excellent long-term stability with <10% variation in device performance over 1800 h. Full characterization data are reported for ( 6) and the intermediates used in its synthesis including single-crystal X-ray structural analysis of all compounds. The paper also describes the ultra-fast dye sensitization and co-sensitization of TiO 2 photo-electrodes in 5 minutes using one or two dyes and the first example of ultra-fast tri-sensitization. The dyes tested include the ruthenium dye N719, the squaraine dye SQ1, the red triphenylamine dye 2-cyano-3-{4-[2-(4-diphenylaminophenyl)vinyl]phenyl}acrylic acid ( 5) and ( 6). DSC efficiencies of 7.5% have been achieved for 1 cm 2 devices co-sensitized using (6) and N719. These efficiencies exceed those recorded for single dye devices and EQE measurements confirm efficient photon capture from two or more dyes in a single photo-electrode. Photo-acoustic calorimetry (PAC) has also been used to measure the energy of the charge separation states formed for (6) and N719, showing a larger value (1.47 eV) for (6) compared to N719 (1.08 eV), whilst a TiO 2 film co-sensitized with both (6) and N719 gave an intermediate value (1.28 eV). These data have been used to calculate dye HOMO, LUMO and l max levels for (6) and N719 leading to important insights for future successful co-sensitization.