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Graphical abstract Highlights • A simple design for constructing tunable WLEDs using a sandwich structure. • A convenient way for realizing tunable WLEDs from cool light to warm light. • A significant advantage for avoiding the negative impact in traditional WLEDs. Abstract Two major problems exist in tunable White Light-Emitting Diodes (WLEDs) that are typically composed of blue-emitting chip, yellow- and/or red-emitting phosphors: (1) the unstable hue of blue-emitting chip, and (2) the harsh conditions (such as high reaction temperature and reductive atmosphere) of traditional red-emitting phosphors. In this paper, we explore a sandwich layer WLEDs structure of ITO (Indium Tin Oxide) films + blue-, yellow- and/or red-emitting pervoskite QDs phosphors + UV-emitting chip to solve the issues. Through changing the number of layers of the three QDs, the correlated color temperature (CCT) was tuned from 8658 to 3961 K, indicating the WLED tuning from cool to warm light. [ABSTRACT FROM AUTHOR]

The combination property of the as-prepared ZnO SPSs on Cu substrate. [Display omitted] • Four zinc sources were used to fabricate ZnO SPS by hydrothermal method. • The ZnO nanoribbons SPS has the biggest CA (168°) and smallest SA (1.8°). • The droplet will exhibit a peach-liked shape after it freezes. • To form SPS is an effective and low cost method for anti-frosting application. Forming superhydrophobic surface (SPS) is an effective way for anti-icing materials in the field of electronic packaging. In this paper, ZnO nanoribbons, regular hexagonal columns, nanowires and irregular hexagonal columns SPS were fabricated by using the Zn(NO 3) 2 , ZnSO 4, Zn(Ac) 2 and ZnCl 2 as zinc sources, respectively. The results show that the ZnO nanoribbons SPS has the longest delayed icing time (16225 s) at temperature of −5℃when compared with other three SPSs. But the anti-icing ability of the ZnO nanoribbons SPS was significantly reduced with the decreasing temperature. This work offers a practical application for enhancing anti-icing ability of Cu-based PCB in electronic packaging. [ABSTRACT FROM AUTHOR]

• Floral ZnO, rod ZnO and Ag/ZnO were successfully synthesized by hydrothermal method. • When citric acid was added into the synthesis of ZnO, the morphology of zinc oxide changed from rod shape to flower shape. • The best degradation rate in the ultraviolet region is 5% Ag/ZnO and the degradation rate reaches 95.3% after 70 min. • Ag can significantly improve the degradation efficiency of ZnO to rhodamine B in the ultraviolet region. In this paper, floral ZnO, rod ZnO and Ag/ZnO with high purity and good crystallinity were successfully synthesized by hydrothermal method. The samples are tested by photocatalysis under UV (ultraviolet) light. The PL (photoluminescence) results show that the addition of Ag enhances the electron-hole separation efficiency of ZnO, which is conducive to photocatalysis. 5% Ag/ZnO has the best photocatalytic activity in the UV region and the degradation rate reaches 95.3% when the irradiation time is 70 min. Floral ZnO and rod ZnO have little difference in degradation rate under ultraviolet light. [ABSTRACT FROM AUTHOR]

• Carbon micro- and nanofibers were prepared by using gyration. • The distribution of fiber diameter showed a normal law with 400-600 nm. • GO changes the orderly arrangement of fibers into a network structure. • The conductivity of carbon nanofibers is greatly improved by adding GO. • When GO was added, the electrode showed excellent electrochemical performance. In this paper, graphene oxide (GO) were added into polyacrylonitrile to prepare carbon nanofiber by using gyration and subsequent carbonization process as to improve their electrochemical properties. The microstructure and electrochemical properties of prepared carbon nanofiber samples were investigated by using scanning electron microscopy and electrochemical workstation, respectively. The effects of the addition amount of graphene oxide and carbonation temperature on the microstructure and electrochemical properties of composite carbon nanofibers were studied. [ABSTRACT FROM AUTHOR]

• High out-of-plane orientation of BaM film with remanence ratio of 0.53 was successfully deposited by PLD method. • It was confirmed that the crystal structure, morphology and magnetism of the film was dependent on the substrate temperature. • XRD and TEM results displayed high degree of orientation of the film deposited at high temperature. In this paper, a hexagonal M-type barium ferrite (BaM) film with a high remanence ratio was deposited on a sapphire substrate by the pulsed laser deposition (PLD) method. The characterization results showed that the film growth at a high substrate temperature (950 °C) has a high out-of-plane orientation, good crystallinity, and smooth surface. Additionally, the hysteresis loops indicated that the film deposited at a high substrate temperature has a high remanence ratio of 0.53, which is higher than that of the other reported BaM films prepared by the PLD method. [ABSTRACT FROM AUTHOR]