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The Sabatier principle is widely explored in heterogeneous catalysis, graphically depicted in volcano plots. The most desirable activity is located at the peak of the volcano, and further advances in activity past this optimum are possible by designing a catalyst that circumvents the limitation entailed by the Sabatier principle. Herein, by density functional theory calculations, we discovered an unusual Sabatier principle on high entropy alloy (HEA) surface, distinguishing the "just right" (ΔGH* = 0 eV) in the Sabatier principle of hydrogen evolution reaction (HER). A new descriptor was proposed to design HEA catalysts for HER. As a proof-of-concept, the synthesized PtFeCoNiCu HEA catalyst endows a high catalytic performance for HER with an overpotential of 10.8 mV at −10 mA cm−2 and 4.6 times higher intrinsic activity over the state-of-the-art Pt/C. Moreover, the unusual Sabatier principle on HEA catalysts can be extended to other catalytic reactions. The advancement of high entropy alloy development is both rapid and challenging. Here, the authors discover an unusual Sabatier principle operating on the high entropy alloy surface, which leads to a notable enhancement in catalytic activity for hydrogen evolution reactions. [ABSTRACT FROM AUTHOR]

Textile-based wearable electronics have drawn increasing attention in recent years, but stable and durable conductive mechanism on textiles has been the challenge. In this study, we propose to fabricate a liquid metal circuit on textile substrates for flexible antennas and wearable sensors via screen printing method. The breakage of liquid metal circuit on cotton/lycra elastic fabrics can be repaired by pressing or heating, and the patterned liquid metal circuits can be removed using sodium hydroxide solution. Furthermore, the liquid metal circuit was designed as a pressure switch for thermal management system with the temperature precisely controllable by tuning the applied pressure. The liquid metal circuit was further designed as a flexible near field communication (NFC) antenna, providing identification capacity such as replacing campus card and protecting children. The maximum bending angle and effective distance of the NFC tag are determined to be 150 and 17.8 mm, respectively. In addition, the as-prepared liquid metal-based fabric sensors can accurately human motion detection in real time, exhibiting great potential in flexible wearable electronics. [ABSTRACT FROM AUTHOR]

Found on the surfaces of transition metal oxides or sulfides are metal cations and oxygen or sulfur anions (Mn+-O2− or Mn+-S2−) with diverse catalytic functions as redox sites (Mn+-O2− → M-□), Brønsted acid sites (M-OH), and Lewis acid–base sites (Mδ+-O2−). These active site pairs often work together in catalyzing the chemical transformation in cascade reactions. This article describes several experimental strategies, combining kinetic and titration methods, to decouple the effects of surface site occupation on turnover rates, identify the kinetic bottlenecks, remove the effects arising from deactivation, as well as elucidate the potential participation of multiple types of active sites. Using a correlative approach in connecting the rate dependencies and titration studies, one could pinpoint the key factors that contribute to the rates and interpret the measured rates in terms of molecular events on the surfaces. [ABSTRACT FROM AUTHOR]

Next-generation smart textiles are regarded as the most straightforward and effective solution to address the growing threats from environment including excessive electromagnetic radiation and global warming. Incorporation of novel materials using advanced fabrication technology has been the reliable technology in developing these smart textiles. Herein, a novel fabrication strategy integrating multi-layer spraying and mechanical compression is proposed to fabricate a liquid metal (LM) and carbon nanotubes (CNT)-decorated multifunctional cotton fabric (CF/LM/CNT). The results demonstrate that the double face-sprayed CF/LM/CNT possess electrical resistance of 0.07 Ω, which is primarily responsible for its unprecedented electromagnetic shielding effectiveness of about 85 dB over the X-band. Moreover, the CF/LM/CNT exhibits excellent heat dissipation and thermal insulation behavior, which is an essential prerequisite for effective thermal management. More importantly, the as-prepared CF/LM/CNT is recycled and reconfigured. This fundamental research work provides a facile and scalable approach to fabricate multifunctional textile materials. [ABSTRACT FROM AUTHOR]

Degradation of formaldehyde (HCHO) in interior decoration has been an urgent issue due to its toxicity nature and potential threats to human health. In this work, manganese dioxide nanoparticles (MnO2 NPs) were in situ grown on the polydopamine (pDA)-templated cotton fabrics for environmentally friendly HCHO degradation applications. The morphology, elemental composition, and crystal structure of the cotton/pDA/MnO2 were characterized by scanning electron microscopy–energy dispersive X-ray spectrum, Fourier transform infrared, X-ray diffractometer and X-ray photoelectron spectroscopy, respectively. The degradation of HCHO by the as-developed cotton/pDA/MnO2 was measured in a self-made quartz reactor, and the stability of adsorption was evaluated by cyclic experiments. The results showed that the HCHO removal efficiency reached to 100% within 20 min after three cycles, suggesting that the as-prepared fabrics exhibited good stability for the degradation of HCHO. The development of MnO2 NPs coated fabrics provides new strategies in degradation HCHO in interior decoration. [ABSTRACT FROM AUTHOR]

In this study, polyacrylonitrile (PAN) @ bamboo shoot shell cellulose nanowhisker (BSCN) @ carbon nanotube (CNT) electrospun composite membrane with enhanced dye adsorption performance was prepared. Methyl blue (MB) was used for dye experiment. The results showed that with the increase of BSCNs, the diameter of the nanofibers in composite membranes gradually increased. When 1.2% BSCNs was added, the removal rate of methylene blue is up to 92.56%, and the kinetics was also investigated. The prepared different composite membranes were characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, thermal gravimetric analysis (TGA) to investigate the surface morphology of fabricated structures, functional groups on the surface of nanofibers and thermal properties. The prepared TEMPO oxidized BSCN based composite membranes can be used as an excellent substrate in the elimination of methylene blue, which is promising in the development of environment-friendly water purifying materials. [ABSTRACT FROM AUTHOR]

High-conductivity yarns with remarkable flexibility and sensitivity have great potential for application in manufacturing wearable electronics. However, the development of electronic textiles (E-textiles) is still limited by the insufficient extents of size manipulation and weight reduction. In this study, a novel nanofiber yarn with a high flexibility, durability, and sensitivity was prepared by a facile electrospinning technique. The composite yarn with silver nanowires used as a reinforcement for polyurethane nanofibers exhibits a high elongation at break (500 %), conductivity (0.4 kΩ/cm), and durability (recovery after 200 tensile cycles). Furthermore, the yarn was used to monitor body language. The results showed distinct fluctuations in resistance in response to subtle changes in expression and small movements of the body. In addition, the composite yarn was examined as a potential electric heater material. The yarn's surface temperature rised to 62.6 °C in 5 s, which proved its excellent electrothermal properties, and it could be realized even at 1 V. The combination of highly conductive structural components, i.e., silver nanowires and the flexible polyurethane nanofibers is a promising design strategy for producing new multifunctional composites for wearable devices. [ABSTRACT FROM AUTHOR]

Smart textiles have got increasing attention for potential application in personal thermal management, wearable human motion monitoring, and healthcare. However, it is still a challenge to prepare a multifunctional electronic textile with water-resistant, electro-thermal response, mechanical-sensitive performance, and antibacterial activities. Here, a multifunctional conductive cotton textile is fabricated by in-situ reduction silver nanoparticles(Ag NPs) on cotton fiber under the assistance of tannic acid, followed decorating with polydimethylsiloxane (PDMS). These obtained multifunctional textiles (cotton/TA/Ag NPs/PDMS textile) not only maintain the innate flexibility, and permeability characteristics of cotton textiles, but also exhibit rapid thermal response, outstanding long-time steady heating performance, and antifouling property. Furthermore, the cotton/TA/Ag NPs/PDMS textiles exhibit excellent strain sensing performance for potential human motions monitoring. Impressively, cotton/TA/Ag NPs/PDMS textiles show resistance to bacterial. Thus, this multifunctional cotton textile provides a new way for the study of the next generation of lightweight, portable, and wearable electronic textile devices. [ABSTRACT FROM AUTHOR]

Multifunctional cotton fabrics were fabricated by coating of anionic waterborne polyurethane (WPU)/Cu2-XSe. The surface morphology of WPU/Cu2-XSe coated cotton fabric was characterized by scanning electron microscopy equipped with energy dispersive X-ray spectroscopy. The microstructural structure was further investigated through Fourier transform infrared (FT-IR) spectra, X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD), and the thermal stability was evaluated by thermogravimetric analysis (TG). The results indicated that WPU/Cu2-XSe nanocomposites coating was successfully deposited on cotton fabric surface. The WPU/Cu2-XSe coated cotton fabrics exhibited high photothermal conversion efficiency, and the coated fabrics were demonstrated for thermal imaging in wearable electronic devices. The coated fabrics also exhibited high photochromic efficiency. The development of multifunctional WPU/Cu2-XSe coated cotton fabrics provides novel strategies for developing smart textiles. [ABSTRACT FROM AUTHOR]