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In this work, we proposed a microwave method to the fast-and-direct preparation of silver nano-ink. The conductive ink is composed of multi-scaled silver nanoparticles (AgNPs) and a few of silver nanorods (AgNRs) as the conductive components. The differently sized nano-silver can provide high conductivity of the written tracks by affording high packing density. The existed one dimensional nanorods can build bridges between nanoparticles to decrease the silver content while maintaining the conductivity of the written pattern. The as-prepared conductive ink can be stored for 20 days without affecting its usability. The written tracks showed satisfying conductivity with a relatively low silver content of 0.025 mol L−1.

Recently, organic thermoelectric (TE) materials have attracted increasing attention in green energy conversion. However, researches on polymer nanostructured TE materials are still scarce, especially for the 1 D nanostructured polymer materials. In this work, 1D poly(3,4-ethylenedioxythiophene) (PEDOT) nanofiber was synthesized by a self-assembled micellar soft-template approach using anionic surfactant sodium dodecyl sulfate (SDS). Then, a flexible and free-standing PEDOT nanofiber film was prepared through a simple vacuum-assisted filtration method. FE-SEM and TEM characteristics real 1D configuration for all the PEDOT nanostructures. Through adjusting the molar ratio of SDS, oxidizing agent FeCl3 and EDOT monomer (nSDS: nFeCl3: nEDOT), nanofiber with different diameter (10–200 nm) and microtopography can be obtained. Electrical conductivity and Seebeck coefficient measurement indicates that the TE properties of PEDOT can be effectively tuned by adjusting its nanostructure, and a variation range as high as three orders of magnitude for the power factors (10-2–101 μW/mK2) can be realized. Due to a more ordered structure caused by the edge-on packing mode of PEDOT chain, the sample prepared with nSDS: nFeCl3: nEDOT = 30:15:7 shows the highest power factor of 7.2 μW/mK2. This value can be further enhanced to 14.4 μW/mK2 by constructing PEDOT nanofiber/SWCNTs composite.

Using concentrating photovoltaic (CPV) cells is an effective method for the low-cost photovoltaic conversion. However, higher temperature and non-uniform surface temperature distribution will result in the electrical output decline of CPV cells and shorten their life time. To obtain higher net output power of CPV cells and prolong their life time, we designed a novel multi-layer manifold microchannel cooling system to effectively lower the cell surface temperature and improve the uniformity of surface temperature distribution. Thermal image analysis indicated that the surface temperature difference of the CPV cells was below 6.3 °C. The multi-layer manifold microchannel had a heat transfer coefficient of 8235.84 W/m2 K and its pressure drop was lower than 3 kPa. The results show that the hybrid CPV cells have a satisfactory net output power due to their lower pumping power and the higher electrical output of CPV cells.

Aluminum–air (Al–air) battery is one of the most promising candidates for next-generation energy storage systems because of its high capacity and energy density, and abundance. The polyacrylic acid (PAA)-based alkaline gel electrolyte is used in all-solid-state Al–air batteries instead of aqueous electrolytes to prevent leakage. The optimal gel electrolyte exhibits an ionic conductivity of 460 mS cm −1 , which is close to that of aqueous electrolytes. The Al–air battery peak capacity and energy density considering only Al can reach 1166 mAh g −1 -Al and 1230 mWh g −1 -Al, respectively, during constant current discharge. The battery prototype also exhibits a high power density of 91.13 mW cm −2 . For the battery is a laminated structure, area densities of 29.2 mAh cm −2 and 30.8 mWh cm −2 are presented to appraise the performance of the whole cell. A novel design to inhibit anodic corrosion is proposed by separating the Al anode from the gel electrolyte when not in use, thereby effectively maintaining the available capacity of the battery.

In this paper a hierarchical multiscale model for microfluidic fuel cells with porous electrodes is developed for the first time. An example of the hierarchical multiscale model for all-vanadium microfluidic fuel cells is presented in this study, in which the diffusion coefficient is used as a bridge between the microscale, mesoscale, and macroscale models. Three-level theories are used to describe the microfluidic fuel cells systems. The development of the model in different time and length scales is emphasized. Results from each scale model are compared with the corresponding experimental and other reasonable data in the literature. We demonstrate that the multiscale model is able to predict the characteristics of microfluidic fuel cells more accurately than before. The hierarchical multiscale model can be a potential tool for developing, designing, and optimizing microfluidic fuel cells.

High-value-added recycling of hazardous waste is a key problem in environmental science and engineering. In previous reports, a hazardous-waste-derived catalyst showed better activity than a catalyst synthesised from pure reagents for the reduction of nitric oxide. The multimetallic nature of hazardous waste was speculated to increase the catalytic activity. In this work, a further investigation was conducted to confirm this speculation. It was found that bimetallic catalysts showed better activity than monometallic ones at 50–200 °C. A bimetallic catalyst removed 75.05% of nitric oxide (990 ppm) at 150 °C, whereas monometallic ones removed only 19.50%. Moreover, the bimetallic catalyst removed 11.46 mmol/g of nitric oxide after 1200 min at 300 °C, which was a much higher concentration than that removed by the monometallic catalyst (2.72 mmol/g). Experimental and simulated Raman spectroscopy revealed that enhanced activity was accompanied by a larger blue shift of the metal band (indicating catalytic centre activity) and a smaller blue shift of the carbon band (indicating reductant stability). In a theoretical calculation, a second metal changed the electron density difference of the catalytic centre and activated the distant reductant, increasing both the low-temperature activity and activity stability. The main result of this study explained the reason bimetallic catalysts outperformed the monometallic ones. Because hazardous waste usually contains bimetallic species, it can be used as a suitable resource for producing effective catalysts.

A new approach for network survivability problem in Internet protocol (IP) over wavelength division multiplexing (WDM) optical network is proposed to enhance the IP layer restorability under physical link failure through logical topology reconfiguration. More specifically, after traffic arrival and departure, reconfiguring the logical topology correspondingly is helpful to minimize the traffic disruption after physical link failure. So, in this paper, this problem is proposed for first time and formulated as an integer linear programming (ILP) problem. And then, two heuristic algorithms are proposed. The performance of proposed algorithms have been evaluated through simulations, and the results show that reconfiguring the logical topology dynamically could achieve more than 20% improvement of the restorability of traffic in IP layer, but with acceptable resource cost.