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n‐Type conjugated polymers (CPs) are crucial in the applications of organic electronics. Direct coupling of electron‐deficient C−H monomer via selective C−H activation, namely C−H/C−H oxidative direct arylation polycondensation (Oxi‐DArP), is an ideal approach toward such CPs. Herein, Oxi‐DArP is firstly adopted to synthesize a high‐performance n‐type CP using a newly developed monomer, i.e. 3,6‐di(thiazol‐5‐yl)‐diketopyrrolopyrrole (Tz‐5‐DPP). Tz‐5‐DPP based homopolymer PTz‐5‐DPP with a molecular weight of 22 kDa has been synthesized via Oxi‐DArP. After n‐doping, PTz‐5‐DPP films exhibited electric conductivity values up to 8 S cm−1 and power factors (PFs) up to 106 μW m−1 K−2. Notably, this PF value is the highest for n‐type polymer thermoelectric materials to date. The Oxi‐DArP synthesis and the excellent n‐type performance of the polymer make this work an important step toward the straightforward and sustainable preparation of high‐performance n‐type polymer semiconductors. [ABSTRACT FROM AUTHOR]

• The abundant carboxyphenyl groups of TCPP-based MOF could not only serve as electrochemical active sites, but also inhibit electrode dissolution in organic electrolyte. • RGO was added into Co-TCPP MOFs as a stack-reducing reagent to synthesize the Co-TCPP MOF/rGO nanosheets composites. The introduction of rGO not only effectively reduced the stacking of MOF, but also formed a continuous conductive network entangled by graphene and MOF in favor of rapid electron transport. • By combining the advantages of Co-TCPP MOF nanosheets and reduced graphene oxide, the Co-TCPP MOF/rGO composite anode exhibits excellent lithium storage performance. The introduction of rGO not only reduces the stacking of MOF effectively, but also facilitates the formation of a continuous conductive network composed of entangled graphene and Co-TCPP MOF in favor of rapid electron transport. More importantly, the ultrathin lamellar structure of Co-TCPP MOF/rGO composite nanosheets could expose more active sites, reduce the diffusion distance of Li+ to the internal electroactive sites, and improve the overall electrical conductivity of the electrode due to the sufficient contact with carbon. [Display omitted] In this study, a novel flower-like Co-TCPP MOF/rGO composite has been successfully synthesized by combining cobalt meso-tetrakis(4-carboxyphenyl) porphyrin (Co-TCPP MOF) and reduced graphene oxide (rGO) via a simple one-pot solvothermal method. The introduction of rGO not only reduces the stacking of MOF effectively, but also facilitates the formation of a continuous conductive network composed of entangled graphene and Co-TCPP MOF in favor of rapid electron transport. More importantly, the ultrathin lamellar structure of Co-TCPP MOF/rGO composite nanosheets could expose more active sites, reduce the diffusion distance of Li+ to the internal electroactive sites, and improve the overall electrical conductivity of the electrode due to their sufficient contact with carbon. When evaluated as anode materials for lithium-ion batteries, the flower-like Co-TCPP MOF/(15 wt%)rGO composite electrode delivers a specific capacity of 1050 mAh g−1 at 100 mA g−1 after 100 cycles. A specific capacity of 650 mAh g−1 can be remained after 300 cycles even at 1000 mA g−1. The superior performance of the Co-TCPP MOF/(15 wt%)rGO composite electrode could be attributed to the introduction of rGO, which prevents the stacking growth of Co-TCPP MOF crystals along the horizontal direction and improves the electrical conductivity. [ABSTRACT FROM AUTHOR]

Single-crystalline chalcopyrite CuInSe2nanorods (CuInSe2NRs) of 50−100 nm in diameter and up to a few micrometers in length have been synthesized solvothermally. High-resolution transmission electron microscopic images of the CuInSe2NRs reveal thed-spacing of 0.335 nm for the (112) crystalline planes and a growth direction along 331. The near-infrared absorption spectrum of the chalcopyrite CuInSe2NRs shows a peak maximum at 1162 nm and an onset at 1262 nm, indicating no apparent blue-shift compared with those of Cu-rich CuInSe2thin films. An intense peak at 175.1 cm-1in the room-temperature Raman scattering spectrum of CuInSe2NRs corresponds to the A1phonon mode of tetragonal CuInSe2chalcopyrite. The narrower full width at half-maximum (fwhm) of 9.5 cm-1for CuInSe2NRs, in comparison with fwhm ∼ 12 cm-1for CuInSe2films, indicates a uniform size distribution and single crystallization in the nanorods. Analysis of the photoluminescence from the single-crystalline CuInSe2NRs measured at 10 K has categorized the emission into seven groups of transitions as characterized by free excitons, bound excitons, conduction band to acceptor levels, and bound excitons at different defects. [ABSTRACT FROM AUTHOR]

Two-layer hybrid anti-reflection (AR) and anti-static (AS) films are formed on the flexible substrates such as polyethylene terephthalate and triacetyl cellulose. The AR layer is composed of two layers; indium-tin oxide (ITO) and thermo-curable fluorinated alkoxy silane compounds (JN7) made by DC magnetron roll sputtering and direct wet coating method, respectively. The polymer for an upper layer was used as the low refractive index (nF=1.35) material, while ITO was chosen as the high refractive index (nITO=2.0) material with good electrical conductivity. The AR property (R<0.8%) and the AS and electromagnetic shielding properties (i.e. the electrical conductivity) were almost the same as the conventional transparent multi-layer AR system. [Copyright &y& Elsevier]