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Mixed-anionic compounds have caught considerable attention due to their flexible coordination manners and abundant physical properties. Four new chalcohalides RbIn4S6Cl (1), CsIn4S6Cl (2), Pb5Sn3S10Cl2 (3) and Pb5Sn3Se10Cl2 (4) were successfully obtained by the high-temperature halide salt flux method. Compounds 1 and 2 have layered structures that consist of octahedral InS6 and aliovalent-anionic InS3Cl units. Compounds 3 and 4 feature 3-D structural frameworks built by [Pb4SnQ8Cl4]6− and [PbSn2Q6]2− (Q = S and Se) polyhedral chains, in which partial Pb2+ cations are coordinated by Q2− and Cl− anions. Compounds 1–4 have optical band gaps close to the wavelength range of visible light and exhibit significant photocurrent responses of 28.75 nA cm−2, 55.12 nA cm−2, 19.58 mA cm−2, and 36.12 μA cm−2 with on/off ratios 30.0, 2.5, 15.7 and 2.6, respectively, implying their potential for photovoltaic applications. To the best of our knowledge, compound 3 has the largest photocurrent response among all non-oxides. In addition, the activation energies of 1–4 are well below 0.3 eV, which makes these compounds interesting for potential applications in electrochemical devices. This work sheds light on the exploration of promising photocurrent response materials in the mixed-anionic compound system. [ABSTRACT FROM AUTHOR]

Copper chalcogenides have drawn considerable attention due to their prominent semiconducting properties. A new Cu-containing semiconductor, namely, CsCuS4 (1), was obtained by a halide salt flux method. Its structure featured 1D infinite ∞1 [CuS4] − chains, where the polysulfide anion S42− was relatively rare in Cu chalcogenides. The compound was multifunctional and exhibited significant photocurrent, humidity sensitivity, and proton conductivity properties. Specifically, it exhibits an "on" state photocurrent response of 0.95 μA cm−2 and an "off" state photocurrent response of 0.55 μA cm−2 with good reversibility. The humidity-sensitive resistance in dry air (10% RH) could reach up to six orders of magnitude higher than that in wet air (100% RH). Compound 1 showed an activation energy of 0.19 eV and may have potential electrochemical applications. [ABSTRACT FROM AUTHOR]

Solvothermal reactions of copper(I) cyanide with tetramethylammonium salts in anhydrous tetrahydrofuran (THF) lead to two novel halogeno(cyano)cuprates namely [Me4N][Cu3(CN)2Br2] with a 1 - D ribbon motif and [Me4N]2[Cu4(CN)5CI] and with a 3-D nanoporous framework. The optical and luminescent studies indicate that both the complexes are potential materials for semiconductors and long-lived highly luminescent material.c

CO direct esterification to dimethyl oxalate (DMO) has important industrial application value. Pd-based heterogeneous catalysts have been often utilized for this reaction. However, the effects of defect structures causing by the different morphologies of the support on the catalytic performance has not been investigated sufficiently. In this work, three different morphologies of CeO2 support (denoted as rod, cube, and octahedron) loading Pd were synthesized, and further investigated their catalytic activities for CO direct esterification to DMO. The Pd/CeO2-rod catalyst exhibited the best CO conversion compared with Pd/CeO2-cube and Pd/CeO2-octa. The results of Raman and XPS show that CeO2-rod has the highest oxygen vacancy concentration than those of CeO2-cube and CeO2-octa. In addition, it was found that partial interfacial electrons transfer from Pd to CeO2 support at the interface from the result of XPS. More intriguingly, the result of in situ DRIRS of CO exhibits that the partial interfacial electrons transfer from CeO2 to Pd, resulting from oxygen vacancies serve as a charge compensator to promote partial electrons transfer. The enriched electron of Pd would promote the adsorption and activation of CO, thus enhancing the catalytic activity. This work will provide a general understanding of the support effect to catalytic performance, which induced by the oxygen vacancies. [ABSTRACT FROM AUTHOR]