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Although the adoption of self‐powered energy harvesting technologies is rapidly increasing, the fabrication of flexible, easy‐to‐assemble, highly sensitive, and energy‐efficient devices continues to pose a significant challenge. Electrospun nanofibrous film‐based triboelectric nanogenerators (TENGs) show great promise for mechanical energy harvesting and self‐powered sensor applications due to their flexibility, wearability, lightweight, and high electrical output. Herein, a polydopamine (PDA)‐treated silver (Ag) nanoparticles (NPs)‐decorated titanium dioxide (PDA‐Ag/TiO2 NPs) is innovatively incorporated into an electrospun Nylon 66 polymer to construct PDA‐Ag/TiO2 nylon composite nanofibrous film (NCNF)‐based TENGs (PAT@NCNF TENGs). The prepared nanofibrous films display high dielectric and conductive properties, improving the output electrical performance of the TENG. The electrical output performance of the PAT@NCNF TENG is systematically studied by varying the filler material embedded in the Nylon 66 polymer. The assembled PAT@NCNF TENG exhibits an electrical output of ≈370 V, ≈15 µA, and ≈5.4 W m−2 with an excellent pressure sensitivity of ≈7.88 V kPa−1. The proposed PAT@NCNF TENG is used to harvest various forms of biomechanical energy and to power electronic gadgets. Finally, PAT@NCNF TENG is effectively employed for multifunctional sensing systems to monitor biomechanical actions, detect the pressure and impact of objects, and facilitate Morse code transmission and human gait monitoring applications. [ABSTRACT FROM AUTHOR]

A novel approach is proposed for combining phosphor materials with triboelectric nanogenerators (TENGs) for mechanical energy harvesting and illumination applications. For this purpose, strongly reddish‐orange‐emitting Ba0.5Sr0.5Nb2O6:0.25 mol Eu3+ (BSNb:0.25Eu) phosphor materials are synthesized. The photoluminescence properties of the synthesized BSNb:0.25Eu are analyzed. The synthesized BSNb:0.25Eu is utilized as a dielectric filler inside a polydimethylsiloxane polymeric film due to its high dielectric properties to improve the overall dielectric properties of the composite film (CF). TENG devices are fabricated using phosphor‐loaded CFs as the tribonegative layer, transparent polyvinyl alcohol as the tribopositive layer, and aluminum as the conductive electrode. All the TENGs operate in a contact‐separation mode, and the highest electrical output is attained by optimizing the phosphor filler concentration in the CF. The optimized TENG exhibits excellent stability in long‐term operational tests, under varying harsh ambient temperatures. Indium tin oxide sputtered on both triboelectric films as an electrode and combined with a transparent hard substrate to obtain a fully transparent TENG. A self‐illuminating TENG (SI‐TENG) is fabricated by integrating near‐ultraviolet light‐emitting diodes between two identical TENGs. The SI‐TENG can harvest the mechanical energy available in the surrounding environment and illuminate it as a light source. Additionally, the proposed phosphor‐loaded polymer films can be employed for optical thermometry and mechanical energy harvesting via SI‐TENG on a large scale. [ABSTRACT FROM AUTHOR]

Hybrid nanogenerators are advanced mechanical energy harvesters capable of simultaneously scavenging multiple types of energy. Additionally, thermochromic materials provide a practical and visually assessable method for real‐time temperature monitoring. In this report, a novel energy harvester and sensing patch (EHSP) is introduced, that utilizes combined piezoelectric and triboelectric effects to harvest mechanical energy efficiently. To optimize the EHSP, various energy harvester configurations are fabricated and tested, and the dielectric properties of triboelectric films are systematically investigated. These improvements are implemented to augment the overall energy harvesting capability. The thermochromic properties of the EHSP are also explored to enhance both the electrical performance and thermal responsiveness. The EHSP demonstrates the ability to generate maximum voltage and current outputs of 350 V and 20.4 µA, respectively. Moreover, it can detect temperature changes within seconds, making it suitable for both energy harvesting and sensing applications. The EHSP is tested in practical scenarios, proving its efficiency as an energy harvester and sensor for everyday human activities. Furthermore, its integration with multiple hybrid nanogenerators showcases its potential for industrial and wearable sensing applications. [ABSTRACT FROM AUTHOR]

With the rise of demand for smart wearable and flexible electronic devices in the modern world, high‐performance hybrid mechanical energy harvesters (HMEHs), which can easily convert biomechanical energy into electricity for powering a variety of portable electronic gadgets and operating smart sensors, have gained extensive interest. Herein, propose piezo/ferroelectric and dielectric niobium (Nb)‐doped bismuth titanate (Bi4Ti3‐xNbxO12, NBTO) plates, are proposed and synthesized by a molten‐salt synthesis technique, and they are further embedded into the poly(vinylidene fluoride‐co‐hexafluoropropylene) (NBTO/PVDF‐HFP) flexible composite film (CF) to construct a flexible HMEH. The prepared NBTO/PVDF‐HFP CFs reveal good piezo/ferroelectricity, β‐phase fraction, and dielectric properties, which can improve the electrical output performance of the HMEH. The 2 wt.% NBTO/PVDF‐HFP CF‐based HMEH exhibits high and stable electrical performance of ≈175 V, ≈5.8 µA, ≈76 µC m−2, and ≈2.02 W m−2, respectively. Furthermore, the durability and mechanical robustness analysis of the HMEH is conducted for several days. The real‐time applications of the HMEH are demonstrated by harvesting the biomechanical energy obtained from daily human activities and powering various portable electronics. Also, the HMEH integrated with an Arduino microcontroller unit is employed as a smart sensor switch for implementing smart home/building stair‐sensing applications and sending emergency e‐mail alerts. [ABSTRACT FROM AUTHOR]

Automated motorized systems are very popular in the modern world of technology and consume a considerable amount of electricity because they are continuously in standby mode. This has driven the need for alternative sustainable energy sources and self-sustainable technologies. Hybrid nanogenerators (HNGs), known as enhanced versions of triboelectric nanogenerators, can be used as a highly efficient mechanical energy harvesting technology with impressive sensing capabilities. In this report, an HNG keypad-based human–machine interface system employing a highly efficient barium zinc fluoride (BaZnF4, (BZF))/polydimethylsiloxane (PDMS) composite film (CF)-based HNG is proposed. BZF with a ferroelectricity/high dielectric constant was synthesized, and different concentrations were loaded inside PDMS. HNGs consisting of BZF/PDMS CFs and paper as the negative and positive triboelectric layers, respectively were fabricated and operated in contact-separation mode. The electrical output from the HNGs was investigated to determine the optimal BZF concentration in the CFs. The optimized HNG with a highly efficient and stable electrical output was implemented to power light-emitting diodes and a liquid-crystal display (LCD) timer. The conversion of abundantly available biomechanical energy into electricity was demonstrated by mounting an HNG onto the human body. A unique HNG keypad was fabricated by integrating 12 similar HNGs in a single 3D-printed structure, which was connected to an Arduino mega board combined with a stepper motor and LCD indicator. The entire system was tested as a security door that was locked when the desired combination of HNGs (equivalent numbers) was sequentially tapped. [ABSTRACT FROM AUTHOR]

Recently, a new class of portable self‐powered electronic systems is developed that utilizes highly efficient hybrid nanogenerators that convert mechanical energy into electricity to power various sensors/small‐scale electronics. This article proposes aluminum titanate (Al2TiO5) microparticles (AlT MPs) loaded poly‐glucosamine (PGA) composite film‐based high‐performance hybrid nanogenerators (HNG) employed as a self‐powered sensor for signal indication and as an intruder sensing platform. Initially, AlT MPs are synthesized and various concentrations are loaded into PGA. HNGs are fabricated using composite films/ polydimethylsiloxane, and Al as the positive/negative triboelectric layers and electrode film, respectively. The fabricated HNGs operate in the contact‐separation mode and their produced electrical outputs are comparatively studied to determine the most suitable AlT concentration. The optimized HNG produces the highest electrical output of ≈211 V, ≈5.5 µA, and 79.5 µC/m2. The optimized HNG is employed as a biomechanical energy harvester to scavenge energy from various biomechanical movements and power portable electronics utilizing the developed highly efficient power management circuit. Thereafter, multiple HNGs are utilized to fabricate a self‐powered wireless sensing system and real‐time intruder sensing platform. The proposed highly efficient HNG‐based self‐powered wireless sensing platform is a promising technology that can be used on a large scale in various applications. [ABSTRACT FROM AUTHOR]

Piezoelectric/ferroelectric zinc tin oxide (ZnSnO3) nanocubes (NCs) are synthesized via a hydrothermal synthesis process. Piezoelectric materials exhibit a superior dielectric property, strong electric dipole moment, and higher piezoelectric coefficient, which results in an improved electrical output of the nanogenerator. The synthesized ZnSnO3 NCs are embedded in triboelectric polydimethylsiloxane (PDMS) polymer to employ the synergistic effect of ZnSnO3/PDMS composite polymer matrix (CPM), which creates a hybrid nanogenerator (HNG). The proposed HNG reveals a high electrical performance due to the improved dielectric constant as well as the synergistic effect of piezoelectricity and triboelectricity. Besides, a conductive filler material such as reduced graphene oxide (rGO) is synthesized using a modified Hummer's method and is further utilized to prepare an rGO‐ZnSnO3/PDMS CPM for improving the electrical output performance of the HNG. Furthermore, the ZnSnO3 NCs and rGO‐ZnSnO3 with different amounts are embedded into PDMS polymeric film to optimize the electrical performance of the HNG. The durability test of the proposed HNG device along with the robustness is investigated. Finally, the proposed HNG device is employed to harvest mechanical movements from daily life human activities to power various portable electronics. [ABSTRACT FROM AUTHOR]

Nanogenerators have attracted much attention in the past few years due to their high conversion efficiency of mechanical energy into electrical energy that is abundantly available in the environment and everyday human life. Enhancing the electrical output performance of nanogenerator using composite polymeric films (CPFs), i.e., piezoelectric materials embedded in triboelectric polymers, has gained potential interest. The CPFs can provide a high relative permittivity and enhanced surface charge density, resulting in an enhanced electrical output. Herein, piezoelectric zinc oxide (ZnO) nanoflakes (ZnO‐NFs) were synthesized by a hydrothermal reaction process and combined with a nylon polymer to prepare a positive triboelectric composite film. Furthermore, a piezo/triboelectric hybrid nanogenerator (ZnO‐HNG) was fabricated with the prepared nylon/ZnO composite film as a positive triboelectric material and PDMS as a negative triboelectric material, respectively. The effect of the loading concentration of the ZnO‐NFs in the nylon polymer on the electrical output was systematically investigated. The optimized ZnO‐HNG exhibited a stable and enhanced electrical output performance with the voltage, current, charge density, and power density values of ≈300 V, ≈9 µA, ≈85 μC m−2, and ≈4.5 W m−2, respectively. Finally, the ZnO‐HNG was attached to the human body to harvest various mechanical motions involved in everyday human life and power various low‐power portable electronics. [ABSTRACT FROM AUTHOR]

Recent advancements in flexible triboelectric nanogenerators (TENGs) have widely focused on converting mechanical energy into electrical energy to power small wearable electronic gadgets and sensors. To effectively achieve this, an efficient energy-converted power management circuit is required. Herein, we report on Aurivillius-type strontium bismuth titanate (SrBi 4 Ti 4 O 15 ) nanoparticles (SBT NPs)-loaded polyglucosamine (PGA) composite film-based flexible TENG to be used for energy harvesting/storage and biomechanical applications. Initially, SBT NPs were synthesized and then, different weight concentrations were loaded into PGA. The TENG devices were fabricated using different wt % composite films (SBT/PGA) and polydimethylsiloxane as positive and negative triboelectric layers, respectively, and aluminum was used as a conductive electrode attached to two tribo films. To evaluate the electrical output from the device, contact-separation operation mode was used. An optimized TENG consisting of 2 wt % SBT/PGA composite film produced the maximum electrical output voltage and current of approximately ∼239 V and ∼7.5 μA, respectively. Efficient TENG energy harvesting and storage circuits have been proposed for storing charges in capacitors and for operating electronic gadgets. The optimized TENG was employed to generate electrical energy from various biomechanical movements. Thereafter, the biodegradability of the composite film was also tested. The fabricated films were completely biodegraded within a few hours. Furthermore, the TENG was utilized as a tap-indication transducer for multipurpose switching applications.

Nanogenerators for acoustic energy harvesting are still in the early stage of development, and many challenges such as the optimization of device structure and the design of efficient and sensitive materials need to be addressed. To solve the above-mentioned problems, herein, advancement in synthesized multiferroic material for hybridizing the nanogenerator and efficient harvesting of various energies such as acoustic, mechanical, and vibrational energies is reported. Initially, bismuth ferrate (BiFeO 3 , BFO)-based composite films are prepared with high ferroelectric and dielectric coefficients. The hybrid nanogenerator (HNG) based on a 3D-printed structure has the highest electrical output which is further improved depending on the BFO loading concentration in the composite film. The 0.5 wt% BFO-loaded PVDF-based HNG offers the enhanced open circuit voltage, short circuit current, and charge density values of ≈30 V, ≈1 µA, and ≈10 µC/m 2 , respectively. The optimized HNG is employed to harvest mechanical energy from everyday human life. Furthermore, the HNG layers are used in the fabrication of a multi-energy harvester/sensor (MEH/S) which can harvest/sense various vibrational and acoustic energies under different acoustic frequencies and amplitudes, respectively. The harvested energy from the MEH/S is tested to power portable electronics., (© 2023 Wiley‐VCH GmbH.)

Mechanical energy is one of the freely available green energy sources that could be harvested to meet the small-scale energy demand. Piezoelectric nanogenerators can be used to harvest the biomechanical energy that is available in everyday human life and power various portable electronics. Herein, a ferroelectric material, i.e., lithium tantalate (LiTaO 3 ), was synthesized and used to fabricate a flexible piezoelectric nanogenerator (FPNG). Generally, ferroelectric materials display a strong electrostatic dipole moment and high piezoelectric coefficient, thus resulting in enhanced electrical performance. First, LiTaO 3 nanoparticles were synthesized and loaded into poly(vinylidene difluoride) (PVDF) to form a piezoelectric film and then, the piezoelectric composite film was sandwiched between two aluminum electrodes to fabricate an FPNG. The effect of the electrical performance of FPNG as a function of the concentration of LiTaO 3 loaded into PVDF was systematically investigated and optimized. The 2.5 wt % FPNG exhibited open-circuit voltage, short-circuit current, and power density values of ∼18 V, ∼1.2 μA, and ∼25 mW/m 2 , respectively. Furthermore, the FPNG revealed good electrical stability and mechanical durability. Finally, the FPNG was employed as a weight sensor to harvest various biomechanical energies and operate low-power- electronics.