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Using ZnO nanowires as needle anodes in gas discharge is helpful for maintaining continuous discharge with a relatively low voltage. It is necessary that the ZnO nanowires are far enough apart to guarantee no electric field weakening and that the nanowire anodes are easy to assemble together with the discharging devices. An AC/DC electric-field-assisted wet chemical method is proposed in this paper. It was used to grow ZnO nanowires directly on discharging devices. The nanowires covered the whole electrode in the case in which only a DC field was applied. Moreover, the tips of the nanowires were scattered, similar to the results observed under the application of AC fields. The average distance between the tips of the highest nanowires was approximately equal to 4 μm, which almost meets the requirement of gas discharge. The research concerning growing ZnO nanowires directly on PCBs shown that, at the current time, ZnO nanowires on PCBs did not meet the requirements of gas discharge; however, in this study, the parameters regarding ZnO nanowire growth were established. [ABSTRACT FROM AUTHOR]

Achieving a high strain under a low electric field is critical for actuator applications, and so is something which has always been pursued. Here, an enhanced strain was achieved by introducing Sr0.7Bi0.2TiO3 (SBT) into Bi1/2(Na0.84K0.16)1/2TiO3 (BNKT) under the guidance of phase boundary engineering and domain design. The introduction of the SBT induces a phase transition from the dominant rhombohedral to the dominant tetragonal and strong relaxor behaviour, as well as increased ergodicity. The enhanced and anti-fatigue strain of 0.57% was obtained in BNKT-8SBT ceramics under a relatively low electric field of 50 kV cm−1, accompanied by a large of 1140 pm V−1. An atomic-resolution displacement vector map reveals the coexistence of R and T nanodomains induced by local structural inhomogeneity. The coexistent nanodomains contribute to a flexible domain structure. This unique domain structure is suggested to be the origin of the relaxor features and the enhanced strains. This result is helpful to understand the excellent performance from a structural point of view and could promote further development of high-performance materials. [ABSTRACT FROM AUTHOR]

Dielectric materials as capacitors with high energy storage performance have received substantial attention for applications as important components in modern electrical and electronic systems. Relaxor ferroelectrics, as one of the popular dielectric materials, have demonstrated extraordinary energy storage performance. However, the origin of this extraordinary performance is not fully understood due to the complex atomic structural heterogeneity. Here, aberration-corrected scanning transmission electron microscopy is employed to study the atomistic structure of a Sr0.7Bi0.2TiO3 lead-free relaxor ferroelectric thin film, which shows high energy density of 77.8 J cm−3, good energy efficiency of 67.8%, and high frequency, temperature and antifatigue stability simultaneously. A slush-like polar structure with 2–4 nm multi-domains and low-angle domain walls, rather than polar nanoregions, is observed, revealed and quantitively described in the Sr0.7Bi0.2TiO3 relaxor ferroelectric thin film. This slush-like polar structure is considered to enable flexible domain switching under an electric field, and is proposed as the mechanism for the high energy storage performance. These results benefit the understanding of the atomic-scale structure of relaxor ferroelectrics and provide guidance for the exploration of new relaxor ferroelectrics with high energy storage performance. [ABSTRACT FROM AUTHOR]