HIPES: Lead-free ferroelectrics for high power energy storage in dielectrics

由化石燃料燃烧引起的能源危机和环境问题是人类面临的重大挑战。近年来，随着绿色和可再生能源的发展，储能材料引起了越来越多的科学和工业关注。可再生能源必须转化为电能以供实际使用。这种形式的能源安全、清洁，非常适合长距离运输，并且可以很容易地转化为其他类型的能源。各种技术已被用于储存来自可再生能源的能量。电介质由于其快速充放电能力（通常在纳秒范围内）而在高功率能量存储应用中发挥重要作用，例如电磁装置和混合动力电动车辆。然而，与具有低功率密度的电池相比，商业介电电容器的能量存储密度非常低。介质电容器的能量密度与铁电体中的电场诱导跃迁密切相关。迄今为止，最好的铁电材料是基于含铅的氧化物。然而，毒性和环境问题促使人们寻找无铅替代品。高熵材料代表了一类有前途的无序多组分材料，具有可定制的特性和潜在的前所未有的性能，包括优异的介电性能。考虑到高熵效应对铁电体结构和电性能的影响，根据高熵概念设计了铁电体的组成，提出了提高环保型无铅铁电体能量密度的策略，为开发大功率储能电容器材料奠定了基础。

The energy crisis and environmental issues caused by the burning of fossil fuels are major challenges facing mankind. In recent years, energy storage materials have attracted increasing scientific and industrial attention, coupled with the development of green and renewable energy sources. Renewable energies must be transformed into electrical energy for practical uses. In this form, the energy is safe, clean, well-suited to long-distance transportation, and can easily be transformed into other types of energy. Various technologies have been used to store energy from renewable sources. Dielectrics play an important role in high-power energy storage applications, such as electromagnetic devices and hybrid electric vehicles, due to their fast charge-discharge capability (typically in the nanosecond range). However, the energy storage density of commercial dielectric capacitors is very low compared to batteries which have low power density. The energy density of dielectric capacitors is closely related to the electric field-induced transitions in the ferroelectrics. To date, the best ferroelectric materials are based on lead-containing oxides. However, toxicity and environmental concerns have prompted the search for lead-free alternatives. High-entropy materials represent a promising class of disordered multicomponent materials with tailorable properties and potentially unprecedented performances, including excellent dielectric properties. Here, considering the high entropy effect on structures and electrical properties of ferroelectrics, the compositions are designed according to the high entropy concept, and the strategies to improve the energy density in environmentally-friendly lead-free ferroelectrics are proposed to enable the development of these materials for high-power energy storage capacitors.