The programmable nature of smart textiles makes them an indispensable part of an emerging new technology field. Smart textile-integrated microelectronic systems (STIMES), which combine microelectronics and technology such as artificial intelligence and augmented or virtual reality, have been intensively explored. A vast range of research activities have been reported. Many promising applications in healthcare, the internet of things (IoT), smart city management, robotics, etc., have been demonstrated around the world. A timely overview and comprehensive review of progress of this field in the last five years are provided. Several main aspects are covered: functional materials, major fabrication processes of smart textile components, functional devices, system architectures and heterogeneous integration, wearable applications in human and nonhuman-related areas, and the safety and security of STIMES. The major types of textile-integrated nonconventional functional devices are discussed in detail: sensors, actuators, displays, antennas, energy harvesters and their hybrids, batteries and supercapacitors, circuit boards, and memory devices.

Smart Textile-Integrated Microelectronic Systems for Wearable Applications

Significantly enhanced energy storage density and efficiency of BNT-based perovskite ceramics via A-site defect engineering

Recently, sustainable green energy harvesting systems have been receiving great attention for their potential use in self-powered smart wireless sensor network (WSN) systems. In particular, though the developed WSN systems are able to advance public good, very high and long-term budgets will be required in order to use them to supply electrical energy through temporary batteries or connecting power cables. This report summarizes recent significant progress in the development of hybrid nanogenerators for a sustainable energy harvesting system that use natural and artificial energies such as solar, wind, wave, heat, machine vibration, and automobile noise. It starts with a brief introduction of energy harvesting systems, and then summarizes the different hybrid energy harvesting systems: integration of mechanical and photovoltaic energy harvesters, integration of mechanical and thermal energy harvesters, integration of thermal and photovoltaic energy harvesters, and others. In terms of the reported hybrid nanogenerators, a systematic summary of their structures, working mechanisms, and output performances is provided. Specifically, electromagnetic induction, triboelectric, piezoelectric, photovoltaic, thermoelectric, and pyroelectric effects are reviewed on the basis of the individual and hybrid power performances of hybrid nanogenerators and their practical applications with various device designs. Finally, the perspectives on and challenges in developing high performance and sustainable hybrid nanogenerator systems are presented.

Hybrid Energy Harvesters: Toward Sustainable Energy Harvesting.

Barium titanate-based energy-storage dielectric ceramics have attracted great attention due to their environmental friendliness and outstanding ferroelectric properties. Here, we demonstrate that a recoverable energy density of 2.51 J cm-3 and a giant energy efficiency of 86.89% can be simultaneously achieved in 0.92BaTiO3-0.08K0.73Bi0.09NbO3 ceramics. In addition, excellent thermal stability (25-100 °C) and superior frequency stability (1-100 Hz) have been obtained under 180 kV cm-1. The first-order reversal curve method and transmission electron microscopy measurement show that the introduction of K0.73Bi0.09NbO3 makes ferroelectric domains to transform into highly dynamic polar nanoregions (PNRs), leading to the concurrently enhanced energy-storage properties by the transition from ferroelectric to relaxor ferroelectric (RFE). Furthermore, it is confirmed by piezoresponse force microscopy that the appearance of PNRs breaks the long-range order to some extent and reduces the stability of the microstructure, which explains the excellent energy-storage performance of RFE ceramics. Therefore, this work has promoted the practical application ability of BaTiO3-based energy-storage dielectric ceramics.

Excellent Energy-Storage Properties Achieved in BaTiO3-Based Lead-Free Relaxor Ferroelectric Ceramics via Domain Engineering on the Nanoscale.

There are imperious demands for developing eco-benign energy storage materials with high-performance in a sustainable society. In this paper, we introduce Sr0.85Bi0.1□0.05TiO3 (SBT) and NaNbO3 (NN) into Bi0.5Na0.5TiO3 (BNT) ceramics through compositional design. The introduction of Sr2+ ions and vacancies at the A-sites constructs relaxor ferroelectrics according to order–disorder theory. The introduction of Nb5+ ions at the B-sites is confirmed to have two major implications. In one way, it boosts a higher induced polarization due to its intrinsic larger polarizability and overall stronger degree of diffuseness. In another, it contributes to forming a core–shell microstructure, as proven using transmission electron microscopy, promoting the breakdown strength (BDS) to a higher level. With the above strategies, our BNT–SBT–4NN ceramics demonstrate excellent energy storage performances with simultaneously ultrahigh energy storage density (W ∼ 3.78 J cm−3), recoverable energy storage density (Wrec ∼ 3.08 J cm−3) and efficiency (81.4%). Furthermore, the ceramics possess excellent discharge energy density (Wd = 0.854 J cm−3) and rapid discharge speed (t0.9 ∼ 100 ns) in a wide temperature range, proving their high application potential. Our results break through the bottleneck of BNT-based ferroelectrics with a general recoverable energy storage density of lower than 3 J cm−3, making the BNT–SBT–4NN ceramic a powerful candidate material for use in energy storage applications.

Enhanced energy storage properties in sodium bismuth titanate-based ceramics for dielectric capacitor applications

Magnetic force driven noncontact electromagnetic-triboelectric hybrid nanogenerator for scavenging biomechanical energy

Temperature-stable dielectric and energy storage properties of La(Ti0.5Mg0.5)O3-doped (Bi0.5Na0.5)TiO3-(Sr0.7Bi0.2)TiO3 lead-free ceramics

A novel ((Bi0.5Na0.5)0.94Ba0.06)1-x (K0.5Nd0.5)xTiO3 lead-free relaxor ferroelectric ceramic with large electrostrains at wide temperature ranges

Dielectric, conductivity and piezoelectric properties in (0.67-x)BiFeO3-0.33BaTiO3-xSrZrO3 ceramics

A novel (0.67-x)BiFeO3-0.33BaTiO3-x(K0.5Nd0.5)TiO3 (KNT100x, x = 0.0, 0.02, 0.04, 0.06, 0.08 mol%) ceramics were fabricated and their microstructure and electrical properties were studied. All samples displayed a pseudo-cubic symmetry, and adding of KNT had little effect on grain size. The dielectric analysis displayed the dispersion increases with the addition of KNT compositions, showing strong relaxor properties. Besides, high dielectric constant (e’) of 23000 and dielectric peak temperature (Tm) of 390 °C remain at 1 kHz in the x = 0.02 sample while the dielectric loss (tanδ) dropped below 0.5 in the range of 30–400 °C, showing excellent electrical insulation performance. In addition, doping of KNT had obvious influence on the strain, and a large strain (Smax) of 0.26% was obtained at x = 0.02 due to the increase of electrical insulation. More importantly, the strain at 50 kV cm−1 enhanced significantly with temperature increasing, reaching a maximum strain of 0.75% with a small hysteresis coefficient of 30% at 110 °C. Particularly, KNT02 exhibited excellent fatigue resistance within 105 fatigue cycles. Presumably these results are attributed to the coexistence of ferroelectric and non-ergodic relaxor domains and the thermally activated domain wall motion.

Nianshun Zhao

Papers

Magnetic force driven noncontact electromagnetic-triboelectric hybrid nanogenerator for scavenging biomechanical energy

Temperature-stable dielectric and energy storage properties of La(Ti0.5Mg0.5)O3-doped (Bi0.5Na0.5)TiO3-(Sr0.7Bi0.2)TiO3 lead-free ceramics

A novel ((Bi0.5Na0.5)0.94Ba0.06)1-x (K0.5Nd0.5)xTiO3 lead-free relaxor ferroelectric ceramic with large electrostrains at wide temperature ranges

Dielectric, conductivity and piezoelectric properties in (0.67-x)BiFeO3-0.33BaTiO3-xSrZrO3 ceramics

Dielectric, impedance and piezoelectric properties of (K0.5Nd0.5)TiO3-doped 0.67BiFeO3-0.33BaTiO3 ceramics