School of Materials Science and Engineering, KIST-UNIST Ulsan Center for Convergent Materials, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea.
Department of Energy Engineering, School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea.
Sci Adv. 2017 May 26;3(5):e1602902. doi: 10.1126/sciadv.1602902. eCollection 2017 May.
A robust nanogenerator based on poly(-butyl acrylate) (PtBA)-grafted polyvinylidene difluoride (PVDF) copolymers via dielectric constant control through an atom-transfer radical polymerization technique, which can markedly increase the output power, is demonstrated. The copolymer is mainly composed of α phases with enhanced dipole moments due to the π-bonding and polar characteristics of the ester functional groups in the PtBA, resulting in the increase of dielectric constant values by approximately twice, supported by Kelvin probe force microscopy measurements. This increase in the dielectric constant significantly increased the density of the charges that can be accumulated on the copolymer during physical contact. The nanogenerator generates output signals of 105 V and 25 μA/cm, a 20-fold enhancement in output power, compared to pristine PVDF-based nanogenerator after tuning the surface potential using a poling method. The markedly enhanced output performance is quite stable and reliable in harsh mechanical environments due to the high flexibility of the films. On the basis of these results, a much faster charging characteristic is demonstrated in this study.
通过原子转移自由基聚合技术控制介电常数，制备了基于接枝聚（丙烯酸丁酯）（PtBA）的聚偏二氟乙烯（PVDF）共聚物的稳健纳米发电机，可显著提高输出功率。该共聚物主要由α 相组成，由于 PtBA 中的π 键合和酯官能团的极性特性，增加了偶极矩，介电常数值增加了约两倍，这得到了开尔文探针力显微镜测量的支持。介电常数的增加显著增加了在物理接触过程中可以在共聚物上积累的电荷密度。纳米发电机在使用极化方法调整表面电势后，产生 105 V 和 25 μA/cm 的输出信号，与原始基于 PVDF 的纳米发电机相比，输出功率提高了 20 倍。由于薄膜的高柔韧性，这种显著增强的输出性能在恶劣的机械环境中非常稳定和可靠。基于这些结果，本研究证明了更快的充电特性。
