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Phase‐junction nanocomposites, made of nanograins with the same composition but different phases, offer a platform to optimize the physiochemical performance of materials. Herein, we demonstrate a straightforward strategy to synthesize Cu2−xS phase‐junction nanocomposites by retaining surface 1‐dodecanethiol (DDT) ligands, in contrast to the traditional method that strips the ligands. As a result, phase junctions between a conventional monoclinic (m) phase and an unconventional metastable tetragonal (t) phase are obtained. The significantly improved power factor is obtained due to the doping of the t‐phase. The phase‐junction interfaces reduce thermal conductivity. Finally, surface regulation of phase junctions pushes the peak zT to 2.1 at 932 K, being the highest reported for environment‐friendly metal sulfides. This work provides a paradigm to optimize thermoelectric performance by controlling phase junctions through surface‐ligand tuning. [ABSTRACT FROM AUTHOR]

Phase‐junction nanocomposites, made of nanograins with the same composition but different phases, offer a platform to optimize the physiochemical performance of materials. Herein, we demonstrate a straightforward strategy to synthesize Cu2−xS phase‐junction nanocomposites by retaining surface 1‐dodecanethiol (DDT) ligands, in contrast to the traditional method that strips the ligands. As a result, phase junctions between a conventional monoclinic (m) phase and an unconventional metastable tetragonal (t) phase are obtained. The significantly improved power factor is obtained due to the doping of the t‐phase. The phase‐junction interfaces reduce thermal conductivity. Finally, surface regulation of phase junctions pushes the peak zT to 2.1 at 932 K, being the highest reported for environment‐friendly metal sulfides. This work provides a paradigm to optimize thermoelectric performance by controlling phase junctions through surface‐ligand tuning. [ABSTRACT FROM AUTHOR]

Two microporous complexes, [Zn(TATAB)(OCH3)] ⋅2 H3O+ ( 1; TATAB=4,4′,4′′-[(1,3,5-triazine-2,4,6-triyl)tris(azanediyl)]tribenzoic acid), [Cu1.5(μ2-O)TATAB*] ( 2; TATAB*=4,4′-{[6-(dimethylamino)-1,3,5-triazine-2,4-diyl]bis(azanediyl)}dibenzoic acid) have been synthesized and characterized by elemental analysis, IR spectroscopy, UV absorption spectroscopy, and thermogravimetric analysis, and by powder XRD and single-crystal XRD analysis. Structural analyses revealed that complex 1 possesses a 3D porous framework with uncoordinated water molecules trapped in the pores; the dimensions of the channels are approximately 29.2×12.3 Å2. Complex 2 has a 3D microporous network structure. In addition, the surface photovoltage and photocatalytic activities were also studied. The photocatalytic properties of the two complexes were investigated by the decomposition of methylene blue under UV and visible-light irradiation. The results revealed that 2 possessea a higher photocatalytic activity than 1 under UV or visible-light irradiation. The potential semiconductor and dye degradation properties of complexes 1 and 2 may be widely applied in the fields of chemical semiconductors and environmental protection in the future. [ABSTRACT FROM AUTHOR]

The reactions of IMes-HCl with bimetallic iron-copper clusters were investigated and it showed that interconversions among bimetallic Fe xCu y(CO) zn- clusters were induced by IMes-HCl. The reaction priority of IMes-HCl with fragments in Fe xCu y(CO) zn- was also investigated and the reaction behaviors of zero valent Fe(CO)4 and divalent Fe(CO)4 with IMes-HCl were discussed. [ABSTRACT FROM AUTHOR]