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In this paper, Bi2212 films were prepared on LaAlO 3 (100) and SrTiO 3 (100) substrates by the sol-gel method using Bi(NO 3) 3 ·5H 2 O, Sr(NO 3) 2 , Ca(NO 3) 2 ·4H 2 O and Cu(NO 3) 2 ·3H 2 O as raw materials. TritonX-100 (TX-100), fatty alcohol poly oxyethylene ether (AEO-9), poly (vinylpyrrolidone) (PVP) and poly (vinyl alcohol) (PVA) were used as surfactants, respectively, to improve the wettability between the sol and the substrate. When glycine and glycolic acid were used as complexing agents, these surfactants were stably miscible with the sols. The effects of different surfactant sol-gel systems on the wettability of substrates as well as the crystallinity, morphology, surface roughness and electrical transport properties of Bi2212 superconducting films were investigated. The results showed that flat and continuous c -axis epitaxial Bi2212 films were obtained using all these sol-gel systems. In particular, TX-100 and AEO-9 as surfactants showed stronger wettability of the sol-gel for both substrates. In addition, the films prepared using polymer surfactants PVP and PVA sol-gel systems showed less surface roughness. The same patterns were found in all the film samples prepared using precursor sols of different complexing agents, and all the films exhibited good electrical transport properties. This work lays a certain research foundation for the preparation of thin films by aqueous solvent sol-gel method. The method also shows great potential in terms of the stability of different sol-gel systems and the improvement of the wettability of different substrates. [ABSTRACT FROM AUTHOR]

Antiferroelectric film capacitors have attracted increasing attention due to their excellent energy storage properties. In this work, PbZrO 3 (PZO) antiferroelectric films have been prepared on the flexible fluorphlogopite (Mica) and rigid Pt/Ti/SiO 2 /Si substrates with a seed layer of LaNiO 3 (LNO) layer by sol-gel process. The microstructure and energy storage properties of the films have been systematically studied. The results show that the Mica-Pt-LNO-PZO (M -LNO-PZO) thin film has an improved energy storage density (W rec) of 16.6 J/cm3 with a charge and discharge efficiency (η) of 50.4%. Furthermore, the flexible thin films exhibit good stability under a wide working temperature range of 25–140 °C and an electric fatigue endurance of 107 cycles. Besides, the capacitive films can endure a bending radius of 4 mm and 104 bending cycles (@ r = 4 mm) with almost unchanged in the energy storage properties. The excellent energy storage properties endow inorganic thin films with great potential in flexible electronic devices. [ABSTRACT FROM AUTHOR]

During the preparation of Bi 2 Sr 2 CaCu 2 O 8+ δ (Bi2212) superconducting thin films by sol-gel method, the complexing agent and sintering conditions can significantly influence the quality and the performance of thin film. In this study, Bi2212 thin films were prepared on single crystal SrTiO 3 (001) substrate, and the phase purity, crystallinity, surface morphology and transport properties were studied particularly with different sintering temperature and time, complexing agent and its ratio to metal ions. Due to relatively low carbon content, tartaric acid (TA) as a complexing agent improved the film quality and transport properties compared with the traditional ethylenediamine tetraacetic acid (EDTA). When the complex ratios of TA to metal ions was 1:1, Bi2212 thin films exhibited good epitaxial properties, a high Bi2212 phase purity and a low surface roughness of 12.74 nm. Simultaneously, under these preparation condition, Bi2212 superconducting thin film showed a higher T c, onset of 93.28 K. [ABSTRACT FROM AUTHOR]