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Among the number of hyperthermia materials, magnetic nanoparticles have received much attention. In this work, we studied the heating characteristics of uniform Fe@Fe 3 O 4 core-shell nanoparticle under near-infrared laser irradiation and external AC magnetic field applying. The Fe@Fe 3 O 4 core-shell nanoparticles were prepared by thermal decomposition of iron pentacarbonyl and followed by controlled oxidation. The prepared uniform particles were further coated with dimercaptosuccinic acid to make them well dispersed in water. Near-infrared derived photothermal study of solutions containing a different concentration of the core-shell nanoparticles was made by using 808 nm laser Source. Additionally, magnetic hyperthermia ability of the Fe@Fe 3 O 4 nanoparticle at 150 kHz and various oersted (140-180 Oe) condition was systemically characterized. The Fe@Fe 3 O 4 nanoparticles which exhibited effective photo and magnetic hyperthermia are expected to be used in biomedical application.

Recent studies of lithium–sulfur (Li–S) batteries have identified that a modified separator plays a critical role in challenging the capacity fading and shuttle effect of lithium polysulfides (LiPSs). Herein, we report a polyaniline-encapsulated hollow Co–Fe Prussian blue analogue (CFP@PANI) for separator modification. The open frame-like hollow CFP was synthesized via oriented attachment (OA). To improve the catalytic effect and electrical conductivity, PANI was coated on the synthesized CFP. The resulting CFP@PANI was applied on the conventional polypropylene (PP) separator (CFP@PANI-PP) with vacuum filtration. With a ketjen black/sulfur (KB/S) cathode with 66% of the sulfur load, the CFP@PANI-PP exhibited an initial capacity of 723.1 mAh g–1 at a current density of 1 A g–1. Furthermore, the CFP@PANI-PP showed stable cycling performance with 83.5% capacity retention after 100 cycles at 1 A g–1. During the 100 cycles, each cycle maintained high coulombic efficiency above 99.5%, which indicates that the CFP@PANI-PP could inhibit LiPS migration to the anode side without a Li+ transport disturbance across the separator. Overall, the CFP@PANI-PP efficiently suppressed LiPSs, resulting in enhanced electrochemical performance. The current study provides useful insight into designing a nanostructure for separator modification of Li–S batteries.

Overall water splitting based on electrocatalysis is an easily constructed and cost-effective technology for achieving clean and renewable hydrogen energy on a large scale. Herein, we demonstrate the investigation of multiscale integrated mushroomshaped cobalt phosphide@nickel-cobalt phosphide (denoted CPNCP) as a catalyst for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline conditions. The catalyst with a unique nano/microscale 3D "body" and "head" structure can be grown directly on a nickel substrate, promoting high conductivity, high hydrophilicity, and effective gas bubble release, bringing in a prospective candidate for practical water splitting devices. Furthermore, the practical relevance of CPNCP as a bifunctional catalyst for the overall water splitting reaction is revealed, with 10 mA•cm −2 to achieve current density at a low overpotential of 1.49 V and maintained at 10 and 200 mA•cm −2 for 40 h with little degradation. Also, the continuous reverse water splitting for over 6 h is capable, demonstrating CPNCP's high endurance toward constant power interruption. The turnover frequencies are calculated to be 3.208 and 1.072 s −1 for HER and OER, respectively, describing an excellent performance of CPNCP. This work may inspire optimizing structures of transition-metal-based nanomaterials, promoting their applications in other renewable energy options.