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A series of reusable and tunable polyacrylonitrile fiber supported catalysts that make use of the cooperative interplay between N -heterocyclic carbene (NHC) Au(III) and amino groups have been developed for synthesis of secondary propargylamines. The yield using immobilized NHC-Au(III) as catalyst is twice as much as that of its small molecule counterpart. Moreover, implementation of a flow system with polyacrylonitrile fiber supported NHC-Au(III) as catalyst leads to a short retention time of 3.3 min and an efficient productivity of 27 mmol/h. The highly catalytic activity of this catalyst is ascribed to the unique hydrophilic microenvironment consisting of NHC-Au(III), -NH 2 and -CN groups in the surface of fiber catalyst. In this microenvironment, the adjacent NHC - Au(III) and amino groups promote the formation of gold-acetylide complex cooperatively with turnover numbers (TON) up to 5200. [ABSTRACT FROM AUTHOR]

• Sulfur host prepared by a unique dual-channel electrospinning method. • WS 2 /WO 3 and MoS 2 /MoO 3 heterostructures enabling anchor of LiPSs. • WX 2 and MoX 2 realized LiPSs adsorption and catalytic conversion. • Excellent energy storage performance is in both coin cell and pouch cell. Due to the dissolution of Lithium polysulfides (LiPSs), the volume expansion, and poor conductivity, practical applications of Lithium-sulfur batteries (LSBs) are not satisfactory. Herein, dual-heterostructure decorated interweaved carbon nanofibers are proposed as sulfur hosts to significantly improve the energy storage behavior of LSBs. The unique structure of the interweaved carbon nanofibers and heterostructures provides more transmission channels for electrons and ions while also accelerating the process. Moreover, the heterostructures induce chemical anchoring and catalytic conversion of LiPSs. As a result, the cathode in the coin cell delivers an initial capacity of 777.9 mAh g−1 at 1C and high retention of 68.59% after 600 cycles. In the pouch cell, the cathode delivers a discharge capacity of 907.8 mAh g−1 and a reversible charging capacity of 913.1 mAh g−1 for the first cycle with an ultra-high sulfur loading up to 9.136 mg cm−2. Beyond that, density functional theory calculations, X-ray photoelectron spectroscopy, symmetric cell, and Li 2 S nucleation tests were adopted to verify the adsorption and catalytic conversion mechanisms of the cathode. This excellent interweaved dual-heterostructure sulfur host provides a novel structural design strategy for efficient chemical adsorption and catalytic conversion of LiPSs, as well as more opportunities for the commercial application of LSBs. [ABSTRACT FROM AUTHOR]

• Targeted design, convenient synthesis and detailed characterization of the catalyst. • Cooperative catalysis, mild conditions and general applicability for CO 2 utilization. • Prominent recyclability, simple separation and efficient gram-scale processes. Herein, a novel fiber-supported N-heterocyclic carbene (NHC) precursor and copper(I) composite (EIMBr-PANF TA @CuI), capable of acting as a cooperative catalyst for cleaner carboxylation of terminal alkynes from CO 2 , is presented. The EIMBr-PANF TA @CuI was synthesized systematically, and the resulting fiber samples from preparation and utilization processes were characterized detailedly. Moreover, the unique fiber-supported composite structure as a cooperative catalyst exhibited the synergistic effect on the activation of CO 2 and terminal alkyne, which corporately contributed to the high catalytic performance on carboxylation for producing a series of alkyl 2-alkynoates in acetonitrile under ambient conditions. Furthermore, EIMBr-PANF TA @CuI was stable to air and moisture, and could be easily recovered with a tiny pair of tweezers and recycled with good activity over 10 runs. In addition, this protocol was convenient and effective for gram-scale experiments and thereby was prospective in practical applications. [ABSTRACT FROM AUTHOR]