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Dielectric elastomer actuators (DEAs) artificial muscle is a typical interdisciplinary research category, which has developed by leaps and bounds in the past 20 years, showing great application prospects in various fields. Upon external electrical stimulation, dielectric elastomers (DEs) display large deformation, high energy density and fast response, affording a promising material candidate for soft robotics. Herein, the working mechanisms, commonly used materials as well as the concepts for improving the performance of DEA materials are introduced. Various DEA driven soft robots, including soft grippers, bioinspired artificial arms, crawling/walking/underwater/flying/jumping soft robots and tunable lenses, are then described in detail. Finally, the main challenges of DEA driven soft robots are summarized, and some perspectives for promoting the practical application of DEAs are also proposed.

Developing an efficiently supported Cu-based catalyst with promoters to substitute the existing non-supported Cu-based catalysts is highly desirable to the Rochow-Müller reaction. Using a simple ball-milling method and CeO₂ support, we prepared a high-performance CuO-ZnO-P-Sn/CeO₂ catalyst by integrating highly dispersed multicomponent promoters of ZnO, Sn, and P with the active component CuO. This catalyst shows a significantly enhanced dimethyldichlorosilane selectivity because these promoters can substantially increase the Cu⁺ content and the formation of an active Cu_xSi phase. This work provides a new approach to efficiently designing Cu-based catalysts for the Rochow-Müller reaction.

The development of industrialization has led to the increased demands for carbon-based energy resources, meanwhile, excessive carbon dioxide (CO₂) emission caused by industrialization has aroused enormous environmental concerns. With the proposal of global carbon neutrality, much attention has been paid to the thermocatalytic hydrogenation of CO₂ into value-added chemicals and fuels, which is widely considered as a promising way to alleviate carbon emission and energy shortage. CO₂ hydrogenation to hydrocarbons mainly undergoes a CO₂-modified Fischer-Tropsch synthesis (CO₂-FTS) route or a methanol-mediated (MeOH) route. However, each route needs to be further optimized and possesses its own advantages and disadvantages. In the present review, the mechanisms and primary intermediates of these two routes are firstly summarized. Hereafter, the current understandings of the relationship among catalytic performance, physical-chemical properties of catalysts and reaction conditions for each route are overviewed according to different target products, including light olefins, gasoline, jet fuel, diesel and aromatics. Finally, we provide an outlook of dual-pathway catalysts on future direction of CO₂ hydrogenation.

Most recent progress on the Suzuki-Miyaura, Heck and Sonogashira cross-coupling reactions, induced by heterobimetallic Pd-Ln coordination polymers as heterogeneous catalysts has been accurately reviewed. Physical-chemical characterization of the Pd-Ln composite materials by adequate physical methods revealed the distinct structure and configuration of the two- and three-dimensional frameworks. The important contribution of the coordination polymers as catalyst supports to finely modulating the catalytic activity and chemoselectivity has been considered. Published results illustrate the high activity and chemoselectivity of Pd-Ln coordination polymers in cross-coupling reactions, excellent catalyst recoverability and recyclability as well as low catalyst loading or metal leaching, under optimized reaction conditions. The particular effect of the solvent, base, aryl halide or related reagents in governing the main steps of the Pd catalytic cycle has been particularly outlined. In addition, the well-established cooperative effect of the lanthanides with palladium, with emphasis on the synergism between different metals in heterobimetallic catalytic systems, has been highlighted.

Swelling-induced morpholine functionalized adamantane-containing poly(aryl ether ketone) (MAPEK) membranes were prepared for vanadium flow batteries. MAPEK membranes were prepared from chloromethylated polymer and morpholine and further swelling-induced with hot phosphoric acid to obtain membranes with enhanced ionic conductivity. The swelling, selectivity, and ionic conductivity of MAPEK membranes were regulated by varying the swelling temperature. Selective swelling-induced microphase separation in MAPEK membranes, forming wider ion transport pathways and resulting in low area resistance. The unique rigid adamantane-containing backbone limited the swelling of membranes. Consequently, MAPEK membranes showed excellent selectivity and conductivity (vanadium ion permeability coefficient of MAPEK membranes was lower than 3.82 × 0⁻⁷ cm²min⁻¹) (Nafion212 membrane, 42.5 × 0⁻⁷ cm²min⁻¹), and MAPEK-150 membrane exhibited low area resistance (0.17  Ωcm²). The vanadium flow batteries (VFB) with MAPEK-150 membrane exhibited high energy efficiency (91.1% at 80 mAcm⁻², 81.4% at 200 mAcm⁻²). Furthermore, MAPEK membranes showed good stability in VFB and oxidative electrolytes. The swelling-induced method utilized in this work is a versatile and facile method to enhance the conductivity of ion-exchange membranes.

Chemical engineering is a broad field in terms of the scope of practice but the discipline has been united by a few intellectually coherent principles. Among them, thermodynamics, reaction kinetics and transport phenomena are often considered as the cornerstones, providing support for the design and operation of diverse chemical processes for power generation and production of industrial goods such as plastics, gasoline and ammonia. Traditionally, these industrial processes use fossil fuels as the raw materials and are responsible for significant greenhouse gas emissions. As fossil-energy-based processes are deemed phasing out , development of alternative routes with renewable energy and sustainable feedstock is calling for the expansion of the knowledge base such that eco-friendly chemical processes can be quantified, controlled and optimized with high precision. This article offers some perspectives on possible engineering developments to accelerate the paradigm shift from fossil fuels to renewable energy.

WO₃ nanoparticles were successfully deposited onto SiO₂/Si substrates equipped with a pair of interdigitated Pt electrodes by heating tungsten filaments in a vacuum chamber. The morphology and structure of the obtained WO₃ nanoparticles were characterized by means of field emission scanning electron microscopy (FESEM) and X-ray diffractometer (XRD). The results revealed that these nanoparticles show a sphere-like structure and their sizes depend on deposing pressure. Furthermore, the NO₂ sensing properties of WO₃ nanoparticles were studied. The intrinsic WO₃ nanoparticles with small size exhibit surprisingly high response to ppb-level NO₂, low detection limit, excellent selectivity, and good stability at a very low operating temperature, demonstrating their potential in monitoring ppb-level NO₂ at low power consumption. In addition, an in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) measurement was carried out to propose the NO₂ sensing mechanism, which demonstrates that adsorbed nitrate and nitrite species are the main species on WO₃ surface. Furthermore, the intensity and the sensing response show the same trend with respect to the temperature, indicating that nitrate and nitrite species play a joint role in NO₂ sensing behavior on WO₃ surface.

Catalytic filters including catalytic bag filters and catalytic filter candles, which couple the filters with denitrification catalysts to obtain the ability to simultaneously remove SO_x, NO_x and dust, have become the promising applied technology for the integrated flue gas treatment because of their huge advantages in reducing the initial investment, floor occupancy and maintenance cost. In this review, we will summarize the recent advances in the development of catalytic filters in terms of their process principles, filter material, denitrification catalysts, structure-function relationships and industrial applications. Moreover, suggestions about the current challenges and future opportunities are also given from the viewpoints of catalysts and filter material design, catalytic filter preparation methods, and their poisoning and regeneration, etc. With the further development of theory and engineering research, the extensive industrial application of catalytic filters in the field of multiple pollutants flue gas treatment is highly anticipated in the future.