Understanding the ion transport behavior of organic ionic plastic crystals (OIPCs) is crucial for their potential application as solid electrolytes in various electrochemical devices such as lithium batteries. In the present work, the ion transport mechanism is elucidated by analyzing experimental data (single-crystal XRD, multinuclear solid-state NMR, DSC, ionic conductivity, and SEM) as well as the theoretical simulations (second moment-based solid static NMR line width simulations) for the OIPC diethyl(methyl)(isobutyl)phosphonium hexafluorophosphate ([P(1,2,2,4)][PF(6)]). This material displays rich phase behavior and advantageous ionic conductivities, with three solid-solid phase transitions and a highly "plastic" and conductive final solid phase in which the conductivity reaches 10(-3) S cm(-1). The crystal structure shows unique channel-like packing of the cations, which may allow the anions to diffuse more easily than the cations at lower temperatures. The strongly phase-dependent static NMR line widths of the (1)H, (19)F, and (31)P nuclei in this material have been well simulated by different levels of molecular motions in different phases. Thus, drawing together of the analytical and computational techniques has allowed the construction of a transport mechanism for [P(1,2,2,4)][PF(6)]. It is also anticipated that utilization of these techniques will allow a more detailed understanding of the transport mechanisms of other plastic crystal electrolyte materials.

Silver bismuth iodides are non-toxic and comparatively cheap photovoltaic materials, but their wide bandgaps and downshifted valence band edges limit their This article is protected by copyright. All rights reserved. performance as light absorbers in solar cells. Herein, we introduce a strategy to tune the optoelectronic properties of silver bismuth iodides by partial anionic substitution with the sulfide dianion. A consistent narrowing of the bandgap by 0.1 eV and an upshift of the valence band edge by 0.1-0.3 eV upon modification with sulfide are demonstrated for AgBiI 4 , Ag 2 BiI 5 , Ag 3 BiI 6 and AgBi 2 I 7 compositions. Solar cells based on silver bismuth sulfoiodides embedded into a mesoporous TiO 2 electron transporting scaffold, and a poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] hole transporting layer significantly outperform devices based on sulfide-free materials, mainly due to enhancements in the photocurrent by up to 48 %. A power conversion efficiency of 5.44 ± 0.07 % (J sc = 14.6 ± 0.1 mA cm -2 ; V oc = 569 ± 3 mV; fill factor = 65.7 ± 0.3 %) under 1 sun irradiation and stability under ambient conditions for over a month are demonstrated. The results reported herein indicate that further improvements should be possible with this new class of photovoltaic materials upon advances in the synthesis procedures and an increase in the level of sulfide anionic substitution.

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The resurgence of interest in the hydrogen economy could hinge on the distribution of hydrogen in a safe and efficient manner. Whilst great progress has been made with cryogenic hydrogen storage or liquefied ammonia, liquid organic hydrogen carriers (LOHCs) remain attractive due to their lack of need for cryogenic temperatures or high pressures, most commonly a cycle between methylcyclohexane and toluene. Oxidation of methylcyclohexane to release hydrogen will be more efficient if the equilibrium limitations can be removed by separating the mixture. This report describes a family of six ternary and quaternary multicomponent metal–organic frameworks (MOFs) that contain the three‐dimensional cubane‐1,4‐dicarboxylate (cdc) ligand. Of these MOFs, the most promising is a quaternary MOF (CUB‐30), comprising cdc, 4,4′‐biphenyldicarboxylate (bpdc) and tritopic truxene linkers. Contrary to conventional wisdom that adsorptive interactions with larger, hydrocarbon guests are dominated by π–π interactions, here we report that contoured aliphatic pore environments can exhibit high selectivity and capacity for LOHC separations at low pressures. This is the first time, to the best of our knowledge, where selective adsorption for cyclohexane over benzene is witnessed, underlining the unique adsorptive behavior afforded by the unconventional cubane moiety.

We present for the first time, the solid state phase behaviour of the organic ionic plastic crystal (OIPC) N-methyl-N-ethyl-pyrrolidinium bis(trifluoromethanesulfonyl)amide, [C2mpyr][NTf2], upon mixing with the sodium salt, Na[NTf2].