We demonstrate that high-quality vertically aligned SnSe nanorod (NR) arrays have been synthesized via a facile chemical vapor deposition method on SiO₂ substrates using Bi powder as catalysts. Both SEM and TEM measurements reveal that this kind of SnSe NR consists of a one-dimensional core and dense two-dimensional branches. Thermistors and photoresistors have been fabricated in situ by directly depositing silver paint on the growth substrates. The thermistor shows the great merits of a broad temperature range (77-390 K), linear input-output characteristic, suitable thermal index and high sensitivity. The photoresistor device exhibits relatively fast response time, linear input-output, high reversibility and stability. In addition, both of the devices have the advantages of low cost, environment-friendliness and easy fabrication. The high performance of SnSe thermistors and photodetectors will make SnSe material promising in industrial multi-function nanodevices.

For highly efficient photoelectrodes, the materials used must have both a broad absorption range and large separation efficiency of photogenerated electron-hole pairs. Type II heterostructures with a ternary shell meet these two requirements and thus are recognized as being an ideal materials system for application in photocatalytic hydrogen production. Here, a ZnO/ZnxCd1-xTe core/shell nanowires array with a broad absorption edge from UV (380 nm) to NIR (855 nm) was fabricated via a chemical vapor-deposition method. More importantly, the ZnO/ZnxCd1-xTe core/shell nanowires array are highly single crystalline, and the composition can be continuously tuned by optimizing the deposition temperature, making the design of the desired photocatalyst possible. As expected, the single-crystalline ternary ZnxCd1-xTe shell greatly enhances the charge separation efficiency and prolongs the lifetime of photogenerated charge carriers, which contribute to the high photocatalytic and photoelectrocatalytic activity under light irradiation. In addition, ZnO/ZnxCd1-xTe core/shell structure show remarkable photocatalytic H2-production activity and high H2-production capability because of the synergistic light absorption of the ternary ZnxCd1-xTe shell and the formation of a type II heterostructure at the interface between the ZnO core and ZnxCd1-xTe shell. This work provides a new material platform for the design of highly efficient solar-fuel devices that demonstrate a broad and controllable absorption from the UV to NIR wavelengths.

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Enantioselective acylation catalyzed by the thioamide modified 1-methylhistidine methyl ester 1 in combination with DABCO-mediated racemization of the substrate led to the efficient dynamic kinetic resolution of meso-1,2-diol monodichloroacetates. In this way, cyclic and acyclic meso-1,2-diol monodichloroacetates can be transformed to the enantiomerically enriched (1S,2R)-heterosubstituted diol diesters which are stable in enantiomerically pure form and can be readily used for further organic transformations.