pyroelectric transportation, chemical, light, photonic systems, electromagnetic radiation, medical applications and so on, is a key question for the sustainable development of our society. [3][4][5][6][7][8][9][10][11][12][13][14][15] Technologies to harvest electrical energy from wind have extensive applications in self-powered systems of wireless electronics, mobile electronics, wearable electronics, civil engineering, and national security because wind energy is one of the cleanest, most abundant, sustainable, and cost-effi cient energies based on the threat of global warming and energy crisis. [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] Some previous researches in nanogenerators were focused on piezoelectric materials, including ZnO, GaN, InN, MoS 2 , polyvinylidene fl uoride, lead zirconium titanate, BaTiO 3 , BiFeO 3 , NaNbO 3 , (1− x )Pb(Mg 1/3 Nb 2/3 )O 3x PbTiO 3 , 0.9525K 0.5 Na 0.5 NbO 3 -0.0475LiTaO 3 , and triangular-belt ZnSnO 3 , where a deformation of the piezoelectric material converted a small-scale mechanical energy into electricity. [18][19][20][21][22][23][24][25][26][27][28] Recently, triboelectric nanogenerators (TENGs) based on the coupling between triboelectrifi cation and electrostatic induction have been developed as a novel means of harvesting energy due to the unprecedented advantages of simple fabrication, light weight, excellent reliability, low cost, high power density, high energy conversion effi ciency, and abundant choices of materials since 2012. [13][14][15][16][17] In particular, wind-induced TENG with fl uttering membranes has been suggested as an alternative to overcome the drawbacks of wind-turbine-based wind energy generator including structural complexity, the large volume and weight, high cost of manufacturing and installation, low effi ciency and noise. [ 3 ] Bae et al. demonstrated that there had been considerable research on the basic dynamics of fl exible structures like fl ags, which could be bent, folded, twisted, or waved. [ 3,29 ] It was reported that the fl utter-driven TENG having small dimensions of 75 mm × 50 mm exhibited the electrical performances: an instantaneous output voltage of 200 V, a current of 60 µA with a frequency of 158 Hz, and an average power of about 0.86 mW at the airfl ow rate of 15 m s −1 . [ 3 ] Meng et al. reported that the airfl ow-driven TENG with the size of 90 mm × 50 mm × 15 mm consisted of an undulating polyimide (Kapton) fi lm and nineunit-segmented Al electrodes on the single substrate, revealing the maximum open-circuit voltage ( V OC ) of 30 V at 103 Hz without segmentation, a rectifi ed short-circuit current ( I SC ) of Wind-driven triboelectric nanogenerators (TENGs) play an important role in harvesting energy from ambient environments. Compared to single-side-fi xed triboelectric nanogenerator (STENG) arrays for harvesting single-pathway wind energy, double-side-fi xed triboelectric nanogenerator (DTENG) arrays are developed to harvest bidirectional wind energy. Electrical performances of the STENG and DTENG can ...

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Bi 1 − x Ce x FeO 3 (x=0, 0.05, 0.1, 0.15, and 0.20) (BCFO) thin films were deposited on Pt/TiN/Si3N4/Si and fluorine-doped SnO2 glass substrates by sol-gel technique, respectively. The effect of Ce doping on the microstructure, electrical and magnetic properties of BCFO films was studied. Compared to counterparts of BiFeO3 (BFO) film, the fitted Bi 4f7/2, Bi 4f5/2, Fe 2p3/2, Fe 2p1/2, and O 1s peaks for Bi0.8Ce0.2FeO3 film shift toward higher binding energy regions by amounts of 0.33, 0.29, 0.43, 0.58, and 0.49 eV, respectively. Raman redshifts of 2–4 cm−1 and shorter phonon lifetimes for the Bi0.8Ce0.2FeO3 film might be related to anharmonic interactions among Bi–O, Ce–O, (Bi, Ce)–O, and Fe–O bonds in the distorted oxygen octahedron. Compared to the pure counterparts, the dielectric and ferroelectric properties of the Bi0.8Ce0.2FeO3 film are improved due to the decreased oxygen vacancies by the stabilized oxygen octahedron. Current density values for the BFO and Bi0.8Ce0.2FeO3 film capacitors are 9.89×10−4 and 5.86×10−5 A/cm2 at 10 V, respectively. The current density–applied voltage characteristics indicate that the main conduction mechanism for the BCFO capacitors is the interface-controlled Schottky emission. Both the in-plane and out-of-plane magnetization–magnetic field hysteresis loops reveal that the saturation magnetization values of the BCFO films increase with increasing the Ce concentration. The enhanced magnetic properties for the BCFO films might be attributed to the presence of Fe2+ caused by oxygen vacancies, the suppressed spiral spin structure, and/or the increased canting angle induced by Ce doping.