A highly efficient catalyst system based on ruthenium-pincer-type complexes has been discovered for N-formylation of various amines with CO2 and H2, thus affording the corresponding formamides with excellent productivity (turnover numbers of up to 1,940,000 in a single batch) and selectivity. Using a simple catalyst recycling protocol, the catalyst was reused for 12 runs in N,N-dimethylformamide production without significant loss of activity, thus demonstrating the potential for practical utilization of this cost-effective process. A one-pot two-step procedure for hydrogenation of CO2 to methanol via the intermediacy of formamide formation has also been developed.

Patterning multiple images within a single element without crosstalk can significantly increase the information capacity and security, but it is challenging to enable the response capability in each image. Now, the patterning of crosstalk‐free yet cooperative‐thermoresponse images (holographic and fluorescent images) is successfully achieved by designing a liquid crystal (LC)/AIEgen system with a unique synergy. The AIEgen's fluorescence intensity is controlled by the LC, while the LC's phase transition is in turn promoted by the AIEgen. The fluorescent image contrast is significantly boosted by efficient energy transfer (ΦET: 96 %) from the LC to the AIEgen. The AIEgen's photocyclization for fluorescent patterning occurs in a zero‐order kinetic manner and can be completed within several minutes when assisted by the LC. The photocyclization conversion is quantitatively dependent on the aggregation size: α∼exp(‐d), and able to reach as high as 98 %.

The significant fire hazards on the polymer-based thermal interface materials (TIM) used in electronic devices are but often neglected. Also, high filler loading with the incident deterioration of mechanical, thermal, and processing properties limits the further application of the traditional polymer-based TIMs. In this work, a ternary TIMs with epoxy resin (EP) matrix, silver nanowires (AgNWs), and a small amount of flame-retardant functionalized graphene (GP-DOPO) were proposed to address the above questions. Briefly, a facile "branch-like" strategy with a polymer as the backbone and flame-retardant molecule as the branch was first used to functionalize reduced graphene oxide (RGO) toward increasing the flame-retardant grafting ratio and RGO's compatibility in matrix, and the resulted GP-DOPO was then in situ introduced into the EP/AgNW composites. As expected, the incorporation of GP-DOPO (2 wt %) can increase the thermal conductivity to 1.413 W/(m K) at a very low AgNW loading (4 vol %), which is 545 and 56% increments compared to pure EP and EP/AgNW, respectively. The prominent improvement in thermal conductivity was put down to the synergetic effect of AgNW and GP-DOPO, i.e., the improving dispersion and bridging effect for AgNWs by adding GP-DOPO. Moreover, the high flame-retardant grafting amount and the excellent compatibility of GP-DOPO resulted in a strong catalytic charring effect on EP matrix, which further formed a robust protective char layer by combining the AgNW and graphene network. Therefore, the flame retardancy of EP/AgNW was significantly improved by introducing GP-DOPO, i.e., the peak heat release rate, total heat release and total smoke production reduced by 27.0, 32.4, and 30.9% reduction compared to EP/AgNW, respectively.

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Photopolymerization-based three-dimensional (3D) printing can enable customized manufacturing that is difficult to achieve through other traditional means. Nevertheless, it remains challenging to achieve efficient 3D printing due to the compromise between print speed and resolution. Herein, we report an efficient 3D printing approach based on the photooxidation of ketocoumarin that functions as the photosensitizer during photopolymerization, which can simultaneously deliver high print speed (5.1 cm h−1) and high print resolution (23 μm) on a common 3D printer. Mechanistically, the initiating radical and deethylated ketocoumarin are both generated upon visible light exposure, with the former giving rise to rapid photopolymerization and high print speed while the latter ensuring high print resolution by confining the light penetration. By comparison, the printed feature is hard to identify when the ketocoumarin encounters photoreduction due to the increased lateral photopolymerization. The proposed approach here provides a viable solution towards efficient additive manufacturing by controlling the photoreaction of photosensitizers during photopolymerization.

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Ah ighly efficient catalyst system based on ruthenium-pincer-type complexes has been discovered for N-formylation of various amines with CO 2 and H 2 ,t hus affording the corresponding formamides with excellent productivity (turnover numbers of up to 1940 000 in as ingle batch)a nd selectivity.U sing as imple catalyst recycling protocol, the catalyst was reused for 12 runs in N,N-dimethylformamide production without significant loss of activity,thus demonstrating the potential for practical utilization of this costeffective process.Aone-pot two-step procedure for hydrogenation of CO 2 to methanol via the intermediacy of formamide formation has also been developed.

Photoresponsive supramolecular gels have aroused continuous attention because of their extensive applications; however, most studies utilize UV light, which inevitably brings about some health and environmental issues.