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In this paper, a novel Pt/CoP/C photo-electro synergistic catalyst was successfully synthesized by a hydrothermal method combined with phosphorus doping treatment. The addition of Vulcan XC-72R is in favor of effectively preventing agglomeration of active catalytic sites, resulting in more uniform and smaller Pt and CoP nanoparticles. The as-obtained Pt/CoP/C shows excellent photo-electro catalytic performance for the HER with simulated solar light irradiation. The optimal hydrogen production is 5384.18 mmol h−1 g−1, which is obviously higher than that of the commercial catalyst (20 wt% Pt/C: 4608.52 mmol h−1 g−1). The research results show that introducing cobalt phosphide into the Pt catalyst can improve the electrocatalytic activity and stability for the HER; in particular, the existence of Co3O4 in Pt/CoP/C leads to an efficient photo-electro catalysis under irradiation, which significantly improves the catalytic activity of Pt. The results above provide a novel strategy for the rational design of cost-effective Pt-based composites towards a fast HER. [ABSTRACT FROM AUTHOR]

In this work, a one-pot solid phase reaction was used to synthesize PtIn/3D-GNs composites with different alloying degrees. The as-synthesized composites were characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), and X-ray photoelectron spectroscopy (XPS). The results indicate that PtIn alloy was formed in the PtIn/3D-GNs composites. However, In(0) content in the composites (denoted as PtIn/3D-GNs (O)) when In2O3 was used as a precursor of In is almost twice as much as that in the composites (denoted as PtIn/3D-GNs (S)) using In(NO3)3 as a precursor of In, which indicates the higher Pt–In alloying degree in PtIn/3D-GNs (O). Electrochemical tests show that PtIn/3D-GNs composites exhibit superior electrocatalytic activity, better stability and enhanced antipoisoning ability toward methanol oxidation reaction (MOR) in comparison with Pt/3D-GNs and the commercial Pt/C. Interestingly, the synergistic effect between the charge separation of In2O3 and the SPR excitation of In(0) under light irradiation contributes to their good electro-photocatalytic performance under simulated sunlight irradiation. Especially, the higher Pt–In alloying degree in PtIn/3D-GNs (O) contributes to its better conductivity, which is responsible for its more efficient electro-photocatalytic properties. [ABSTRACT FROM AUTHOR]

A fast islanding detection tool can help power dispatchers monitor and control power system operations. Frequency monitoring network (FNET) is a low cost and quickly deployable wide-area phasor measurement system at the distribution system level. The frequency disturbance recorder (FDR) in FNET is actually a single-phase phasor measurement unit (PMU) installed at ordinary 120 V outlets in the sense that it measures the voltage phase angle, amplitude, and frequency from a single-phase voltage source. Based on the data collected by the FDRs deployed in the North American power grid, two islanding detection methods, the frequency difference method and the change of angle difference method, are proposed. The nine real cases recorded, including islanding cases, generation trip cases, load shedding cases and oscillation cases, are presented to verify the proposed methods of islanding detection. Sensitivity analysis on the thresholds of the frequency deviation and angle deviation is done based on the real measurement data for obtaining the insensitive interval of two thresholds. The results show that the proposed methods can correctly detect power system islanding, and will not be falsely triggered by generation trips, load shedding and system oscillations. [ABSTRACT FROM PUBLISHER]

Recent developments in smart grid technology have spawned interest in the use of phasor measurement units to help create a reliable power system transmission and distribution infrastructure. Wide-area monitoring systems (WAMSs) utilizing synchrophasor measurements can help with understanding, forecasting, or even controlling the status of power grid stability in real-time. A power system frequency monitoring network (FNET) was first proposed in 2001 and was established in 2004. As a pioneering WAMS, it serves the entire North American power grid through advanced situational awareness techniques, such as real-time event alerts, accurate event location estimation, animated event visualization, and post event analysis. Several papers published in the past several years discussed the FNET structure and its functionality. This paper presents some of the latest implementations of FNET's applications, which add significant capacities to this system for observing power system problems. [ABSTRACT FROM PUBLISHER]