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A novel method is presented for drastically improving the local surface plasma resonance (LSPR) effect of noble metal nanoparticles (NPs) and nanoclusters (NCs). This is realized by magnetizing particles comprising a ferrimagnetic core and a noble metal nanoshell. In this study, we prepared Fe 3 O 4 @SiO 2 @Ag composite particles. Ag NPs and NCs had the size of 10–15 nm and 2–3 nm, respectively. The photoluminescence (PL) intensities of ZnO and YAG:Ce substrates coated with the magnetic composite particles increased by 160 % and 50 %, respectively, after magnetization under a magnetic field of 18 mT compared to the unmagnetized state. The activity of Ni-foam-based-Fe 3 O 4 @SiO 2 @Ag working electrode for water electrolysis was also significantly improved after magnetization. The increasing rate of current density after magnetization was 226 mA∙cm−2/0.1 V, which is higher than 158 mA∙cm−2/0.1 V before the magnetization. The mechanism for drastic performance enhancement of PL and water electrolysis postulates that after magnetization, the remanence of the ferrimagnetic Fe 3 O 4 core provides a local magnetic field to strengthen the local electric field in the confined area of Ag NPs/NCs. It was confirmed by the higher intensity of peaks in Raman spectroscopy and contributed to the enhancement of LSPR effect. This efficient and practical approach to magnetization-induced LSPR improvement has potential application prospects in LSPR-related fields. [Display omitted] • A novel approach to magnetization-induced drastic LSPR improvement is proposed. • After magnetization under 18 mT, PL intensities of Fe 3 O 4 @SiO 2 @Ag-coated ZnO and YAG:Ce were elevated to 2.6- and 1.5-fold. • After magnetization, water electrolysis efficiency of Fe 3 O 4 @SiO 2 @Ag was significantly improved by the local magnetic field. [ABSTRACT FROM AUTHOR]

A mixture of cationic and anionic fluorinated surfactants can form faceted vesicles and punctured lamellar phase when there is excess surface charge, in which both cationic and anionic fluorinated surfactants are stiff in the membrane as phospholipids in the frozen “crystalline” or “gel” phase. Here, a model was established to demonstrate the mechanism of the formation and transition of the aggregates with different morphologies. With excess cationic surface charge, the gel-like faceted vesicles and punctured lamellae can transform into smooth-shaped vesicles at high temperature. The freeze-fracture transmission electron microscope (FF-TEM) and X-ray diffraction (XRD) were used to identify the segregation and phase sequence of semi-fluorinated cationic and anionic surfactant membranes with different excess surface charge. [ABSTRACT FROM AUTHOR]

In this work, a complete green synthesis approach to reduced graphene oxide-Ag nanoparticles hybrid by using tea polyphenol as both reducing and stabilizing agent is reported. On the one hand, tea polyphenols can efficiently reduce graphene oxide and adsorb on the surface of the reduced graphene oxide. On the other hand, the surface adsorbed tea polyphenols can further in situ reduce Ag ions to Ag nanoparticles and stabilize them. The structure and physicochemical properties of the resulting nanohybrid were characterized in detail by UV–vis spectroscopy, Fourier transformation infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy and high-resolution transmission electron microscopy. The obtained results indicated that Ag nanoparticles distributed uniformly on the surface of the functionalized graphene. Meanwhile, the so-formed hybrid material could be well dispersed in water forming a homogeneous dispersion due to the stabilization of tea polyphenols. This nanohybrid, combining the unique catalytic properties of Ag nanoparticles with the excellent adsorption and electron transfer ability of graphene, exhibited enhanced catalytic activity toward the reduction of 4-nitrophenol by NaBH 4 . [ABSTRACT FROM AUTHOR]

Abstract: Herein we report on a simple and reliable hydrothermal method to prepare superhydrophobic TiO2 surface on fluorine-doped tin oxide (FTO) coated glass substrates. The surface shows a novel cactus-like cluster structure composed of TiO2 submicron rods with lengths ranging from 1μm to 3μm. After modified with stearic acid, the as-prepared surface shows a remarkable superhydrophobicity with a water contact angle as high as 160° and a sliding angle smaller than 5°. Furthermore, the surface also exhibits non-sticking properties. [Copyright &y& Elsevier]