Synchronous Synthesis and Immobilization of Metal Phthalocyanine for Aerobic Oxidation of Styrene

In this study,the precursor 4-(4-carboxy-phenoxy)phthalonitrile(CPPN)was first bonded onto the silica gel surface modified with poly(glycidyl methacrylate)(PGMA)(PGMA/SiO2)to prepare CPPN-PGMA/SiO2,and metal phthalocyanine(MPc;M=Co,Fe,Cu,Mn)was supported on the PGMA/SiO2 surface to prepare MPc-PGMA/SiO2 by synchronous synthesis and immobilization with phthalonitrile and metal salt in the solution.The chemical composition and surface morphology were characterized by the Fourier transform infrared(FTIR)spectroscopy,UV-Vis spectroscopy,scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS),and thermogravimetry analysis(TGA).The catalytic performance of MPc-PGMA/SiO2 in epoxidation of styrene was also investigated with molecular oxygen acting as the oxidant.The results show that MPc-PGMA/SiO2 can efficiently and selectively catalyze molecular oxygen for oxidation of styrene to styrene oxide under mild conditions.However,the catalytic activity differs substantially depending on the central metal,and a highest catalytic activity is achieved by CoPc-PGMA/SiO2.The CoPc-PGMA/SiO2 amount and temperature can also affect the catalytic oxidation of styrene,and at normal atmospheric pressure,a maximum conversion rate of styrene(99%)and selectivity of styrene oxide(53%)are obtained using 0.1 g of CoPc-PGMA/SiO2(22.61μmol of CoPc)at 100℃ for 6 h.CoPc-PGMA/SiO2 also has excellent reusability,and the conversion rate of styrene is still over 90%after 5 cycles.

Organophosphine ligand derived sandwich-structural electrocatalyst for oxygen evolution reaction

The synchronous construction of metal phosphate and phosphorus-doped carbon structures is of great significance to innovate the design,synthesis,and application of catalysts,as these phosphoruscontaining composite materials have shown a remarkable contribution to electrocatalysts.However,their preparation procedure generally involves using large amounts of excess phosphorus sources for phosphorization,which inevitably release poisonous PH_(3) or dangerous phosphorus vapor.Here,a strategy for in-situ formation of FePO_(4) embedded in P-doped carbon 2D nano film(FePO_(4)/PdC)is developed using a highly integrated precursor,which is a small molecular organophosphine ligand,1,1’bis(diphenylphosphine)ferrocene(DPPF).The multi-source precursor DPPF that contains Fe,P,and C is molecular-vapor-deposited on the nickel foam(NF)supported ZIF-67 nanosheets to obtain the composite catalyst,namely DPPF-500/ZIF-67/NF.FePO_(4)/PdC encapsulated the ZIF-67 derived Co/N-doped carbon matrix(Co NC)to form a sandwich structure FePO_(4)/PdC@CoNC.The constructed catalyst shows good performance for OER,requiring an overpotential of only 297 m V to deliver 600 m A/cm^(2) with a Tafel slope of 42.7 m V dec^(-1).DFT calculations demonstrate that the synergistic effects between the metal active center and P-doped carbon film reduce the energy barriers and improve electron transport.This method of constructing P-containing catalysts overcomes the demand for additional P sources to realize eco-friendly fabrication and yields a unique structure with good catalytic activity.