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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]

[Display omitted] • A-IGZO thin-film transistors with 4-nm HfO x gate insulator were developed. • Electrical characteristics of the a-IGZO transistors were investigated. • Interface between a-IGZO and HfO x was improved. • Thinning limitation of HfO x gate insulator was discussed. In recent years, high- k gate dielectrics have attracted increasing attention in amorphous oxide semiconductor (AOS) thin-film transistors (TFTs), due to the urge for stronger gate controllability in advanced applications of high integration density. In this work, the ultra-thin top-gate insulator of atomic-layer-deposited (ALD) HfO x was developed for the amorphous indium-gallium-zinc oxide (a-IGZO) TFTs. Despite the good electrical characteristics of the 4-nm HfO x -gated a-IGZO transistor, its reliability is considerably poor and ascribed to the abundant interface defects, for example, oxygen vacancies. The interface reaction between HfO x and a-IGZO during the ALD process is clarified to be responsible for such defect generation. To prevent the oxygen-related reaction, the a-IGZO channel is pre-treated using the strong oxidizing plasma, contributing to significantly enhanced electrical stabilities. However, the further thinner HfO x would readily increase the gate leakage current, since the electron can easily tunnel through the ultra-thin HfO x due to the low conduction band offset between HfO x and AOS. The 4-nm ALD HfO x together with the pre-oxidization contributes to the optimal performance and stability of top-gate a-IGZO TFT. [ABSTRACT FROM AUTHOR]

A durable conducting polymer electrodes with low impedance, antifouling, and electrochemical stress tolerance could be fabricated by electro-depositing zwitterionic PEDOT on ITO, Au, and stainless steel substrates, where the cohesion and interfacial adhesion of PEDOTs are significantly strengthened by dopamine moieties. We envision it could address synchronously the nonspecific interaction and the physical failure issues of conducting polymer bioelectrodes. [Display omitted] • Features low impedance, antifouling, and electrochemical stability. • Significantly strengthened cohesion and interfacial adhesion. • DOPA dramatically enhances the charge injection capability of zwitterionic PEDOT. • Synchronously address the specific interaction and physical failure issues. Conducting polymers are emerging as a very attractive type of electro-materials for bioelectronic devices, owing to their low impedance, high charge injection limit, and small modulus. However, the efforts to create stable and long-lasting conducting polymer electrodes are challenged by biofouling and the physical failure of electrodes. Here, we develop a durable conducting polymer electrode based on EDOT copolymers expressing zwitterionic phosphorylcholine and DOPA moieties, which enable low impedance communication, excellent protein/cell resistance, and long-term stable operation. This antifouling conducting PEDOT electrode shows much enhanced interfacial adhesion with substrates and cohesion in water than all the other tested PEDOT conducting polymers. Its wet lap shear strength with substrates is three times higher than the pristine PEDOT; it can tolerate 20 h of sonication treatment in water, while the three control PEDOT electrodes all start to collapse within minutes. We further find that the antifouling PEDOT can tightly integrate with diverse substrates (Au, ITO, and stainless steel); this strengthening approach works effectively for all the tested three hydrophilic PEDOTs. We finally demonstrate the robustness of the antifouling PEDOT on a homemade electrode array with a not compromised impedance after being electrically stimulated in the physiological environment for 24 h. [ABSTRACT FROM AUTHOR]

The composite membranes consisting of silver nanowires (AgNWs) embedded in polylactic acid (PLA) nanofiber were successfully fabricated by one-pot electrospinning. The PLA/AgNWs composite membranes exhibited immediate silver release and local photothermal effect under NIR irradiation, which contributed to excellent antibacterial property, and simultaneously balanced biocompatibility. [Display omitted] • PLA/AgNWs composite nanofiber as wound dressing was developed by one-pot electrospinning. • Photothermally antibacterial capability of AgNWs was exploited for the first time. • The PLA/AgNWs composite membrane presented high strength, superior flexibility and NIR-induced self-peeling property. • Balanced antibacterial and biocompatible properties were achieved due to NIR-induced silver release and local temperature increase. Bacterial infection is the key factor challenging the success of wound healing. In view of the low and short-term antibacterial effects of traditional wound treatment, a photothermal activated antibacterial platform based on silver nanowires (AgNWs) embedded in polylactic acid (PLA) nanofiber membranes was fabricated by electrospinning in this study. SEM images showed that smooth and continuous PLA/AgNWs composite nanofibers with diameter distribution ranging from 200 to 700 nm were obtained. The composite membranes possess moderate hydrophobicity and self-peeling characters, which may contribute to prevent secondary injury during the removal of the dressing. Excellent water vapor permeability also could meet the requirement of wound dressing. Importantly, the presence of AgNWs endow the PLA/AgNWs membranes with not only enhanced plasticity, but also excellent antibacterial properties due to the near infrared (NIR) triggered silver ion release and local photothermal effect. Such NIR-controlled antibacterial action is also beneficial for achieving good biocompatibility. Therefore, the produced PLA/AgNWs composite nanofiber membrane is expected to be a promising candidate that can prevent bacterial infection and promote skin repair. [ABSTRACT FROM AUTHOR]