摘要 : Phase change materials (PCMs) with excellent energy storage capacity and approximately constant temperature during the phase transition process can absorb and store thermal energy from their surroundings and release it when needed, thereby improving the energy utilization efficiency. However, thermal energy storage requires the temperature of PCMs above their melting points by passive heat absorption, which lacks of proactive control and has great limitations in actual applications. Emerging photo-responsive materials bring some new potentials to the PCM field owing to their distinct response to light and other special features, which can meet the specific requirements such as photothermal conversion in extreme environments. Meanwhile, photo-responsive materials have integrated some new functions into PCMs other than thermal energy storage. However, a comprehensive overview of multifunctional photo-responsive composite PCMs is still missing. Herein, we provide a comprehensive review of the state-of-the-art applications of photo-responsive PCMs. The mechanisms, current developments and further perspectives concerning multifunctional photo-responsive composite PCMs are also highlighted.

摘要 : The presence of organic contaminants in industrial effluents is an environmental concern of increasing global importance. One innovative technology for treating contaminated industrial effluents is nanoscale zero-valent iron supported on biochar (nZVI/BC). Based on Transmission Electron Microscopy, X-Ray Diffraction, and Brunauer-Emmett-Teller characterizations, the nZVI was well dispersed on the biochar and aggregation was dramatically reduced. Methyl orange (MO) served as the representative organic contaminant for verifying the effectiveness of the composite. Using decolorization efficiency as an indicator of treatment effectiveness, increasing doses of nZVI/BC yielded progressively better results with 98.51% of MO decolorized by 0.6 g/L of composite at an nZVI/BC mass ratio of 1:5. The superior decolorization efficiency of the nZVI/BC was attributed to the increase in the dispersion and reactivity of nZVI while biochar increasing the contact area with contaminant and the adsorption of composites. Additionally, the buffering function of acid-washed biochar could be in favor of maintaining the reactivity of nZVI. Furthermore, the aging nZVI/BC for 30 day was able to maintain the removal efficiency indicating that the oxidation of nZVI may be delayed in the presence of biochar. Therefore, the composite of nZVI/BC could represent an effective functional material for treating wastewater containing organic dyes in the future.

摘要 : AbstractHerein, a novel of Co(OH)[email protected] nanomaterials with unique structure as the catalyst for activating peroxymonosulfate (PMS) to degrade bisphenol A (BPA) is reported. The properties of as-prepared catalyst were tested by diverse of characterization techniques. Importantly, the Co(OH)[email protected] activates PMS to degrade BPA more efficiently (96.3% within 40 min) and stably than traditionally Co3O4 and CoO nanomaterials. Different influence factors of BPA degradation were also examined, including different catalyst, pH, temperature, BPA concentrations, PMS dosage, catalyst dosage and co-existing ions. The existence of Cl− and H2PO4− exhibit distinct positive synergistic effects on the catalytic process. The XPS and ICP techniques were applied to illustrate that the leach amount of cobalt ion was very litter. Thus, the reusable ability of Co(OH)[email protected] without significant efficiency loss after multiple cycles. These results demonstrate that Co(OH)[email protected] is an promisingly effective catalyst to activating PMS for BPA remove.

摘要 : We investigate the spatially optical solitons shedding from Airy beams and anomalous interactions of Airy beams in nonlocal nonlinear media by means of direct numerical simulations. Numerical results show that nonlocality has profound effects on the propagation dynamics of the solitons shedding from the Airy beam. It is also shown that the strong nonlocality can support periodic intensity distribution of Airy beams with opposite bending directions. Nonlocality also provides a long-range attractive force between Airy beams, leading to the formation of stable bound states of both in-phase and out-of-phase breathing Airy solitons which lways repel in local media.

摘要 : Phase change enthalpy and thermal conductivity are the two essential parameters for practical applications of shape-stabilized phase change materials (ss-PCMs). Herein, hierarchical three-dimensional (3D) reduced graphene porous carbon support PCMs have been successfully synthesized by carbonizing a graphene [email protected] –organic framework ( [email protected] ) template, which simultaneously realizes large phase change enthalpy and high thermal conductivity. During the carbonization process, MOFs were converted into hierarchical porous carbons, whereas GO was reduced to high-thermal-performance reduced graphene (rGO). Thus, a hierarchical 3D porous carbon structure with high porosity and large specific surface area was obtained, which provided a suitable condition for encapsulating PCMs. Furthermore, the pores of carbon stabilized the PCMs by capillary force and surface tension. The interaction between the PCM molecule and rGO significantly decreased the interfacial thermal resistance and made the composites reveal high thermal conductivity. Furthermore, the 3D network structure promoted the stretching and crystallization characteristics of the stearic acid molecule in the confined pore space, which enhanced the heat release efficiency. Compared with the rGO/MOF-5-C support, the hierarchical 3D structure of [email protected] revealed a thermal conductivity of 0.60 ± 0.02 W m –1 K –1 , which was 27.7% improvement, with large phase change latent heat of 168.7 J g –1 , which increased by 18.5%. Additionally, the obtained ss-PCMs showed transient thermal response and good durability, indicating its promising potential in thermal energy storage application.

摘要 : AbstractThe modification of electronic structure can significantly affect electrocatalytic activity. An architecture art of Pt-skinned PtAg bimetallic nanotubes is successfully synthesized, delivering much higher catalytic activity and better stability toward methanol electrooxidation than PtAg bimetallic nanoparticles and commercial Pt/C catalysts. Theoretical studies reveal that the Pt skin on PtAg bimetallic nanotubes prominently optimize the electronic structure of Pt to greatly enhance the dissociative adsorption of methanol while increasing CO poisoning resistance for fast electrode kinetics, high catalytic current density and stability. This work offers a low Pt loading but highly active anode catalyst for direct methanol fuel cells, demonstrating that rationally tuning the electronic structure by well-controlling surface morphology in nanoscales could open new opportunities to greatly improve the electrocatalytic properties.

摘要 : Rechargeable Zn–air battery is a promising alternative to the widely used lithium–ion battery. Its practical use, however, is hindered by low power density, unsatisfactory energy efficiency, poor durability, and unstable voltage output. Here, we demonstrate a bifunctional catalyst for oxygen evolution and oxygen reduction reactions based on 3D MXene coupled with nitrogen-doped cobalt selenide nanocrystals (N-CoSe 2 /3D Ti 3 C 2 T x ). Combining experimental characterizations and density functional theory (DFT), the excellent performance is ascribed to enhanced intrinsic activity of CoSe 2 due to electron transfer from MXene, N doping which lowers the reaction energy barriers, and 3D MXene architecture which provides large specific surface area, high porosity, and good conductivity. Moreover, Zn–air battery equipped with the developed N-CoSe 2 /3D MXene as the air cathode exhibits better power/energy densities and long-lasting cycling life (over 500 cycles) compared with that of mixed Pt/C and RuO 2 .

摘要 : Abstract MoS 2 nanosheets, a typical kind of layered transition metal dichalcogenides with the 2D structure and many unique physical and chemical properties, have attracted a lot of research interests in various fields. Typically, MoS 2 nanosheets present similarities to graphene in terms of their large surface area and strong absorbance in near‐infrared region, which in combination with their easily functionalized surface make them promising nanoplatforms in biomedical applications. Herein, the progress of MoS 2 nanosheets and their composites in the area of nanomedicine, with the emphasis on their synthesis and modification strategies, their biomedical applications in biosensing, imaging and therapy, as well as evaluations of their in vivo behaviors and toxicology profiles are summarized. Finally, the challenges and opportunities of applying MoS 2 ‐based nanomaterials in the biomedicine areas will be discussed.

摘要 : Abstract Diclofenac (DCF), one of the typically recalcitrant pharmaceuticals, has been frequently detected in groundwater in recent years. This work investigated the performance of DCF degradation by thermally activated persulfate (PS) to further understand its application in in situ chemical oxidation (ISCO) for DCF-contaminated groundwater. The effects of various factors, including activation temperature, solution pH, PS/DCF ratio, and common constitutes, e.g., HCO 3 ? , Cl ? and humic acid, and the toxicity of transformation products were evaluated. The results indicated that the oxidation of DCF was well-fitted with a pseudo-first-order kinetic model, and the rate constants increased with the elevated temperatures. The rate constants from 50–70 °C were further fitted to the Arrhenius equation, yielding an activation energy of 157.63 kJ·mol ?1 . In addition, the oxidation of DCF was highly pH-dependent, with the rate constants rapidly decreased from pH 5 to 7, then slightly increased at the alkaline pH. The presence of a low dosage of Cl ? (0–10 mM) promoted the degradation of DCF, whereas high Cl ? addition (>10 mM) inhibited DCF degradation. HCO 3 ? exhibited a negligible effect on DCF removal, while natural organic matters, e.g., humic acids, lightly inhibited DCF degradation. The rapid degradation of DCF was also confirmed in the real groundwater sample, which might be attributed to the pH drop during the reaction. Moreover, the radical quenching experiments revealed that sulfate radicals (SO 4 ·- ) was the dominant reactive species for DCF oxidation. Finally, the acute toxicity of the DCF solution, as tested with a bioluminescent assay, was gradually decreased during the reaction, indicating that a thermally activated PS oxidation was a promising alternative approach for DCF-contaminated groundwater remediation.