Pursuing high-energy-density dielectric materials is desirable for the growing demands of energy storage for dielectric capacitors in modern electric power systems. Herein, a simple titanium/sol–gel-derived amorphous aluminium oxide (Ti/AmAO) film is firstly presented. The structural evolution was that double dielectric layers of a compact TiO₂ layer and an Al₂O₃/TiO_x layer self-grow simultaneously at a Ti/AmAO interface under a high electric field. The high resistivities of the TiO₂ layer (an order of magnitude of 10⁹ Ω cm) and the Al₂O₃/TiO_x layer (an order of magnitude of 10¹¹ Ω cm) and the improved AmAO film contribute to improving the breakdown strength, and the high dielectric constant of the TiO₂ layer (up to 28.1) serves to yield a high dielectric constant. Therefore, the interfacial evolution endows the film with a high breakdown strength of up to 548 MV m⁻¹ and a high dielectric constant of 15.9. An energy density as high as 20.9 J cm⁻³ at 545 MV m⁻¹ is achieved. Meanwhile, a growth model for the compact layers is proposed to comprehensively understand the interfacial behaviour. This work extends a novel approach of introducing interfacial evolution to improve the energy storage capacity of a dielectric capacitor.

中文翻译：

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由于钛/溶胶-凝胶衍生的无定形氧化铝界面上自生双介电层而产生的超高能量密度†

对于现代电力系统中对介电电容器的能量存储的增长的需求，追求高能量密度的介电材料是合乎需要的。本文首先介绍了一种简单的钛/溶胶-凝胶衍生的无定形氧化铝（Ti / AmAO）膜。结构上的演变是致密的TiO ₂层和Al ₂ O ₃ / TiO _x层的双介电层在高电场下同时在Ti / AmAO界面上自生长。的TiO 2的高电阻率₂层（10数量级⁹ Ω厘米）和Al ₂ ö ₃ /氧化钛_X层（10数量级¹¹Ωcm）和改进的AmAO膜有助于提高击穿强度，而TiO ₂层的高介电常数（最高28.1）有助于产生高介电常数。因此，界面演变赋予该膜以高达548MV m ^-1的高击穿强度和15.9的高介电常数。在545 MV m ^-1处实现了高达20.9 J cm ^-3的能量密度。同时，提出了致密层的生长模型，以全面了解界面行为。这项工作扩展了引入界面演化的新方法，以改善介电电容器的储能能力。