Designing polytypic homojunction is an efficient way to regulate photogenerated electrons and holes, thereafter bringing desired physical and chemical properties and being attractive photocatalysts for solar-to-hydrogen conversion. However, the high-yield and controllable synthesis of well-defined polytypes especially for multinary chalcogenide - the fundamental factor favoring highly efficient solar-to-hydrogen conversion - has yet to be achieved. Here, we report a general colloidal method to construct a library of polytypic copper-based quaternary sulfide nanocrystals, including CuZnSnS, CuCdSnS, CuCoSnS, CuMnSnS, CuFeSnS, CuInSnS and CuGaSnS, which can be synthesized by selective epitaxial growth of kesterite phase on wurtzite structure.
View Article and Find Full Text PDFHierarchically structured chiral luminescent materials hold promise for achieving efficient circularly polarized luminescence. However, a feasible chemical route to fabricate hierarchically structured chiral luminescent polycrystals is still elusive because of their complex structures and complicated formation process. We here report a biomimetic non-classical crystallization (BNCC) strategy for preparing efficient hierarchically structured chiral luminescent polycrystals using well-designed highly luminescent homochiral copper(I)-iodide hybrid clusters as basic units for non-classical crystallization.
View Article and Find Full Text PDFAlthough solar-driven water splitting on semiconductor photocatalysts is an attractive route for hydrogen generation, there is a lack of excellent photocatalysts with high visible light activity. Due to their tunable bandgaps suitable for superior visible-light absorption, copper-based quaternary sulfides have been the important candidates. Here, we first assessed the preferred facet of wurtzite Cu-Zn-In-S for photocatalytic hydrogen evolution reaction using the relevant Gibbs free energies determined by first principle calculation.
View Article and Find Full Text PDFHighly luminescent inks are desirable for various applications such as decorative coating, art painting, and anticounterfeiting, to name a few. However, present inks display low photoluminescent efficiency requiring a strong excitation light to make them glow. Here, we report a highly luminescent ink based on the copper-iodide/1-Propyl-1,4-diazabicyclo[2.
View Article and Find Full Text PDFAll-inorganic lead halide perovskite nanocrystals (NCs) are potential candidates for fabricating high-performance light-emitting diodes (LEDs) owing to their precisely tunable bandgaps, high photoluminescence (PL) efficiency, and excellent color purities. However, the performance of pure red (630-640 nm) all-inorganic perovskite LEDs is still limited by the halide segregation-induced instability of the electroluminescence (EL) of mixed halide CsPbIBr NCs. Herein, we report an effective approach to improving the EL stability of pure red all-inorganic CsPbIBr NC-based LEDs via the passivation of potassium bromide on NCs.
View Article and Find Full Text PDFCarpesium abrotanoides L. (CA) is widely used as a medicinal plant in Asia. The biological activities of the extract from the roots of Carpesium abrotanoides L.
View Article and Find Full Text PDFHeterocrystalline polytype nanostructured semiconductors have been attracting more and more attention in recent years due to their novel structures and special interfaces. Up to now, controlled polytypic nanostructures are mostly realized in II-VI and III-V semiconductors. Herein, we report the synthesis and photoelectrochemical properties of Cu-based ternary I-III-VI2 chalcogenide polytypic nanocrystals, with a focus on polytypic CuInS2 (CIS), CuInSe2 (CISe), and CuIn(S0.
View Article and Find Full Text PDFPolytypic nanocrystals with zinc blende (ZB) cores and wurtzite (WZ) arms, such as tetrapod and octopod nanocrystals, have been widely reported. However, polytypic nanocrystals with WZ cores and ZB arms or ends have been rarely reported. Here, we report a facile, solution-based approach to the synthesis of polytypic Cu2CdSn(S1-xSex)4 (CCTSSe) nanocrystals with ZB-derivative selectively engineered on (000±2)WZ facets of WZ-derived cores.
View Article and Find Full Text PDFColloidal synthesis of kinked ultrathin ZnS nanorods/nanowires with mixed phases using tiny Ag2S nanocrystals as catalysts is reported. It is found that chloride ions can induce the controlled morphology transition from straight to kinking. The synthetic parameters modulating the growth of kinked ZnS nanorods/nanowires are systematically investigated.
View Article and Find Full Text PDFPt-Ni alloy nanocrystals with controlled architectures (multi-arms and flowers) have been synthesized via a simple colloid chemistry method. The crystal surfaces possess abundant low-coordination defect sites, where the reaction kinetics of methanol oxidation can be improved, resulting in the catalysts exhibiting better stability and higher resistance to poisoning.
View Article and Find Full Text PDFCeria (CeO2) nanorods with well-defined surface planes can be synthesized and utilized for the hydrogenation of nitroaromatics. The CeO2 nanorods containing a {110} plane can efficiently and selectively catalyse the hydrogenation of nitroaromatics with N2H4 as a reducing agent, while nano-ceria with a {100} or {111} plane shows poor performance for the reaction.
View Article and Find Full Text PDFThe wurtzite-derived Cu₂ZnSn(S(1-x)Se(x))₄ alloys are studied for the first time through combining theoretical calculations and experimental characterizations. Ab initio calculations predict that wurtzite-derived Cu₂ZnSnS₄ and Cu₂ZnSnSe₄ are highly miscible, and the band gaps of the mixed-anion alloys can be linearly tuned from 1.0 to 1.
View Article and Find Full Text PDFEven colloidal polytypic nanostructures show promising future in band-gap tuning and alignment, researches on them have been much less reported than the standard nano-heterostructures because of the difficulties involved in synthesis. Up to now, controlled synthesis of colloidal polytypic nanocrsytals has been only realized in II-VI tetrapod and octopod nanocrystals with branched configurations. Herein, we report a colloidal approach for synthesizing non-branched but linearly arranged polytypic I(2)-II-IV-VI(4) nanocrystals, with a focus on polytypic non-stoichiometric Cu(2)ZnSnS(x)Se(4-x) nanocrystals.
View Article and Find Full Text PDFOver 10 g of non-stoichiometric Cu(2) ZnSnSe(4) colloidal nanocrystals for thermoelectric applications are prepared after one single reaction. The obtained pellet made from the colloidal nanocrystals shows a peak ZT value of 0.44 at 450 °C, which is similar to those of state-of-the-art Cu(2) ZnSnSe(4) -based bulk materials at the same temperature.
View Article and Find Full Text PDFUnique Cu(2)S-PbS heteronanostructures with good photothermal conversion effect have been synthesized for the first time by a Cu(1.94)S nanocrystal seed mediated colloidal solution-phase growth method. The present nanocrystal seed mediated growth method may be extended for the growth of other unique semiconductor heteronanostructures.
View Article and Find Full Text PDFWe report a solution-based synthesis of monodispersed Cu(2)CdSnSe(4) nanocrystals and a study on the thermoelectric properties of these wide-band-gap dense materials compacted from nanocrystals for the first time. With the help of copper dopants and selenium vacancies generated during wet-chemistry synthesis, a large increment in the power factor is observed, and the dimensionless figure-of-merit ZT reaches a peak value of 0.65 at 450 °C.
View Article and Find Full Text PDFMonoclinic beta-silver vanadate (beta-AgVO(3)) nanoribbons with widths of 300-600 nm, thicknesses of ca. 40 nm, and lengths of 200-300 microm can be easily synthesized in high yield directly from a hydrothermal reaction between V(2)O(5) and AgNO(3) in a solution containing a small amount of pyridine. The results demonstrated that the formation of single-crystal AgVO(3) nanoribbons is strongly dependent on the reaction temperature, especially, the presence of pyridine and its dosage.
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