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• An original activated carbon is prepared using golden needle mushroom roots. • As-prepared AC-5 has excellent physical and chemical properties. • The AC-5 electrode exhibits a high specific capacitance of 360.4 F/g. • Such novel activated carbon shows a great potential prospect in supercapacitors. Herein, an original activated carbon (AC) is prepared using golden needle mushroom roots and potassium hydroxide. After carbonization under 500 °C, AC-5 exhibits good graphitization degree, appropriate nitrogen and oxygen elements, large specific surface area, and micro-meso porous structures. Notably, AC-5 as electrodes in supercapacitors has excellent electrochemical performances, e. g. high specific capacitance (360.4 F/g), impressive rate capability (77 %, from 10 mV/s to 200 mV/s), and outstanding cycling durability (99.56 %, after 10,000 cycles). [ABSTRACT FROM AUTHOR]

• The flexible nonwoven/sliver paste composite (NSPC) is fabricated using a screen printing strategy. • The NSPC has a high total shielding effectiveness value of ∼59.3 dB. • Such NSPC shows great potential in the development of high-performance electromagnetic interference shielding applications. In this work, an innovative screen printing strategy is applied to fabricate lightweight flexible electromagnetic interference (EMI) shielding materials. The polypropylene (PP)-based nonwoven fabric (PNF) shows a low total shielding effectiveness (SE T) value of ∼ 0.3 dB because PNF possesses low conductivity and porous fabric structure. However, the nonwoven/sliver paste composite (NSPC) coated with a thin layer of silver paste has a high SE T value of ∼59.3 dB. Moreover, the reflection makes significant contribution to EMI SE T when incident wave enters the materials, indicating the reflection dominated shielding mechanism rather than absorption. [ABSTRACT FROM AUTHOR]

A sodium titanate-carbon (Na 2 Ti 3 O 7 /C) composite as an anode material for sodium-ion batteries (SIBs) is successfully synthesized via a moderate method (500 °C). It can deliver charge capacities of 161 mA h g −1 and 91 mA h g −1 at current densities of 0.05 C and 10 C, respectively. The material can be cycled at 0.2 C for 400 cycles without capacity or voltage decay. This low cost and environmentally friendly Na 2 Ti 3 O 7 /C exhibits excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

High capacity anode material Li 2 MoO 4 powders with and without carbon coating are successfully synthesized via a thermal polymerization method. X-ray diffraction, scanning electron microscopy and transmission electron microscopy are employed to analyze their structures. Galvanostatic cell cycling is used to compare their electrochemical properties. The carbon-coated Li 2 MoO 4 can deliver charge capacities of 669 mAh g −1 and 255 mAh g −1 at current densities of 90 mA g −1 and 1800 mA g −1 , respectively, exhibiting much better electrochemical performance than the carbon-free Li 2 MoO 4 . [ABSTRACT FROM AUTHOR]

• The carbon nanofibers with interconnected and porous structures are fabricated using a facile and novel strategy. • The formation of interconnected structures between fibers mainly stems from the aldolization of glutaraldehyde and starch. • The all-solid-state supercapacitors made from IPCNF electrodes have excellent electrochemical performances. In this study, a facile strategy is introduced to fabricate interconnected and porous carbon nanofibers for electrode materials to improve the electrochemical performances of supercapacitors. The well-developed all-solid-state supercapacitor shows specific capacitances of 71 and 57 F g−1 at current densities of 0.25 and 5 A g−1, as high as ∼ 80% retention rate. The energy density calculated based on supercapacitor device is as high as 9.8 Wh kg−1 at a power density of 125 W kg−1 and the maximum power density is 64.1 kW kg−1. Almost 100% capacity has been maintained after 10,000 charge and discharge cycles. [ABSTRACT FROM AUTHOR]

Abstract: The upconversion optical characteristic and brightness of Y2O2S:Yb,Ho phosphors are investigated. It is shown that Y2O2S:Yb,Ho exhibits NIR, red, green, blue and even ultraviolet-blue emission bands under 980 nm pumping. Moreover, Y2O2S:Yb,Ho shows excellent upconversion luminescence and its upconversion brightness is 2.2 times to that of the commercial Y2O2S:Yb,Er phosphors. The upconversion mechanism is discussed: the green and NIR emissions are due to two consecutive energy transfer from Yb3+ to Ho3+, and the blue and red emissions can be explained as a loop-like mechanism. [Copyright &y& Elsevier]

• B-site precursor method can effectively inhibit the appearance of second phase. • B-site precursor method can obtain high reactivity Mg 4 Nb 2 O 9 powders. • B-site precursor method can promote integrality of the crystal structure. Mg 4 Nb 2 O 9 ceramics have been prepared by B-site precursor method in this work. Experimental results demonstrate that the uniform particles-size distribution of Mg 4 Nb 2 O 9 powders can be obtained, which exhibit high reactivity to promote the grain growth of Mg 4 Nb 2 O 9 ceramics. Moreover, the Mg 4 Nb 2 O 9 ceramics via B-site precursor method can be sintered at a wide range of sintering temperature from 1275 to 1375 °C with single phase Mg 4 Nb 2 O 9 composition and high crystallinity. Compared to the conventional solid-state method, the Mg 4 Nb 2 O 9 ceramics prepared by B-site precursor method exhibit excellent Q × f value by above 168,756 GHz. [ABSTRACT FROM AUTHOR]

Abstract: The up-conversion luminescence properties of trivalent-rare-earth ion-doped orthotantalates are studied under 980 nm laser diode excitation. The results indicate that YTaO4:Tm3+/Yb3+ emits blue and strong infrared emissions respectively corresponding to 1G4→3H6 and 3H4→3H6 transitions of Tm3+ ions, while YTaO4:Er3+/Yb3+ produces strong green and weak red emissions, resulting from 2H11/2/4S3/2→4I15/2 and 4F9/2→4I15/2 transitions of Er3+ ions, respectively. In contrast to three excellent up-conversion phosphors, viz. NaYF4:Er3+/Yb3+, Y2O2S:Er3+/Yb3+ and Y2O3:Er3+, YTaO4:Er3+/Yb3+ shows not only strong green emission, but also larger intensity ratio of green to red emission. In addition, it is found that LaTaO4: Er3+/Yb3+ shows the minimum quenching concentration of Yb3+ and weakest up-conversion emission intensity, and the main peak presents blue shift (8 nm/556 nm) as compared with YTaO4:Er3+/Yb3+ and GdTaO4:Er3+/Yb3+. The distinct luminescent characteristics of LaTaO4: Er3+/Yb3+ can be attributed to the larger difference of radius between doped ion and La3+ ion. [Copyright &y& Elsevier]

A one-way water transport (also called OWT) cotton fabric is prepared by depositing a thin layer of hydrophobic polymer microspheres/nanospheres formed during one-step electrospray on one side of the hydrophilic cotton fabric. Rough surface resulted from the deposited microspheres/nanospheres mainly contributes to the hydrophobicity of electrosprayed layer and the layer thickness plays an important role in determining the water transport ability. OWT ability is observed in the cotton fabric with the electrosprayed layer thickness between 11 μm and 26 μm; when the layer is thinner than 11 μm or over 26 μm, the fabric shows a two-way or blocked water transport ability. This novel OWT fabric can be used in “smart” textiles for various applications. [ABSTRACT FROM AUTHOR]

• Polydopamine (PDA) and carbon nanotubes (CNT) were constructed onto carbon fiber (CF) surface. • Surface morphology and wettability of modified CF were characterized. • Tensile and bending properties of CF-PDA-CNT/PLA composites were obtained and analyzed. Polydopamine (PDA) and carbon nanotubes (CNT) were successively incorporated onto carbon fiber (CF) to enhance surface activity. The impact of PDA and CNT on wettability and mechanical properties of the resulting composites were revealed. Fiber reinforced polylactic acid (PLA) composites were prepared. The results indicated an improved wettability for PDA-CNT modified fibers. Simultaneously, the tensile and bending curves showed brittle and plastic fracture, respectively. Mechanical properties of CF-PDA-CNT/PLA composite significantly outperformed those of CF/PLA composite. The bridging effect of PDA on the CF surface allowed for a tight bond with the matrix PLA, and provided effective load transfer between the matrix and fibers. The application of PDA and CNT on surface modification provides a novel approach for the study of fiber modification. [ABSTRACT FROM AUTHOR]

• The JCF is designed through a one-side deposition followed by in-situ polymerization. • JCF-60 possessed a good vapor generation rate and photothermal conversion efficiency. • JCF shows great potential in solar-driven water evaporation applications. Herein, a Janus cotton fabric (JCF) with polypyrrole (PPy) layer was prepared through one-side ultrasonic atomization deposition followed by the in-situ polymerization. The PPy layer was robust on the fabric and showed excellent light absorbance ability (∼99%). And the JCF with 60 min one-side deposition (JCF-60) showed good photothermal conversion ability with the vapor generation rate of 1.45 kg m−2h−1 and the photothermal conversion efficiency of 91.0% in dyed water purification. It can be expected to large scale applications in solar-driven water evaporation. [ABSTRACT FROM AUTHOR]