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• NH 4 + and PO 4 3- co-precipitated with Mg2+ generating from the sacrificial Mg anode and were recovered as struvite. • High-purity struvite can be partly deposited on and separated from cathode plate. • Electric field improved the cake layer structure, thus mitigating membrane fouling. • Electrochemical reactions provided alkalinity and effectively inhibited anaerobic acidification. Severe membrane fouling and the inability to remove/recover nitrogen and phosphorus are bottlenecks of anaerobic membrane bioreactors (AnMBRs) for large-scale application in wastewater treatment. Herein, an electrochemical AnMBR with a Mg anode-membrane module (electro-AnMBR) was built and showed good performance in terms of membrane fouling mitigation and nutrient recovery during sewage treatment. Compared with the traditional AnMBR, membrane fouling in the electro-AnMBR was reduced by up to 30%. The application of an electric field decreased the zeta potential, viscosity, and EPS concentration of the sludge-water liquor in the electro-AnMBR, which could improve the cake layer structure and thus enhance water permeability. Meanwhile, 26% of NH 4 + and 48% of PO 4 3- co-precipitated with Mg2+ generating from the sacrificial Mg anode and were recovered as struvite deposited onto cathode in the electro-AnMBR. Hydrogen evolution provided a relatively alkaline pH environment, resulting in struvite electrodeposition on the graphic cathode, which partly separated the formed struvite from the sludge with a purity of 77%. In the electro-AnMBR, the electrochemical reactions provided alkalinity and effectively inhibited anaerobic acidification. The applied voltage of 0.6 V reduced the relative abundance of methanosaeta, but increased that of methanosarcina, which is also beneficial for the membrane anti-fouling. [Display omitted] [ABSTRACT FROM AUTHOR]

The secondary recombination of photogenic charge carriers caused by structural defects at the interface of BaTiO 3 /KNbO 3 heterojunction is successfully suppressed by the built-in electric field generated by the piezoelectric effect in BaTiO 3 and KNbO 3. BaTiO 3 /KNbO 3 composite photocatalyst exhibits excellent degradation performance for direct lake blue 5B dye (DLB 5B) under the synergistic effect of piezocatalysis and photocatalysis. [Display omitted] • BaTiO 3 /KNbO 3 heterostructure photocatalysts were successfully prepared for the first time. • BaTiO 3 /KNbO 3 presented good piezo-photocatalytic activity in degrading direct lake blue 5B dye under light irradiation and ultrasonic vibration. • The synergistic effect of piezocatalysis and photocatalysis on the separation and transfer of charge carriers was proposed. In order to reduce the secondary recombination of photogenic charge carriers caused by the structural defects at the interface of traditional heterostructure photocatlysts, and the charge shielding effect of static condition on the built-in electric field in ferroelectric/piezoelectric photocatalyst, two typical piezoelectric photocatalysts, BaTiO 3 and KNbO 3 , were successfully compounded into a series of BaTiO 3 /KNbO 3 heterostructure photocatalysts for the first time. BaTiO 3 nanoparticles with good crystallinity are uniformly distributed on the surface of KNbO 3 prism to form the BaTiO 3 /KNbO 3 heterostructure. The piezo-response force microscopy (PFM) results and piezo-photocatalytic degradation experiments stimulated by ultrasonic vibration and light irradiation show that the separation efficiency of photogenic charge carriers and degradation performance are enhanced by the synergistic effect of piezocatalysis and photocatalysis. The piezo-photocatalytic degradation efficiency of BaTiO 3 /KNbO 3 over direct lake blue 5B dye can reach up to 93.3%. The reaction rate constant of 0.3BaTiO 3 /0.7KNbO 3 over the target dye is 4.44 and 8.57 times higher than that of BaTiO 3 and KNbO 3. This work will provide a promising paradigm to degrade organic pollutants by using synergetic effect of piezocatalysis and photocatalysis, which perhaps facilitates the practical applications of piezo-photocatalytic technology in the environmental field. [ABSTRACT FROM AUTHOR]

A smart cathode coating layer is designed to enhance the high-temperature safety of all-solid-state lithium batteries. Based on the spontaneous polarization-induced built-in electric field, ferroelectric coatings could enhance lithium ion transport at the cathode/electrolyte interface. At hazardous (high) temperatures, ferroelectric coatings transform into paraelectric phases, hindering the transport of lithium ions and slowing down the heat release caused by electrochemical reactions. [Display omitted] [ABSTRACT FROM AUTHOR]