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Simple Summary: With the rapid development of aquaculture, searching for alternative lipid sources to fish oil has become an important task for the aqua-feed industry. Lard is regarded as a valuable alternative lipid source. Basa fish (Pangasius bocourti) offal oil also has a large annual production and high potential to be used in fish feeds. Evaluation of the efficacy of lard and Basa fish offal oil in fish feeds will provide useful information for their application in aquaculture. Both lard and Basa fish offal oil have high levels of saturated fatty acids and monounsaturated fatty acids. The "n-3 LC-PUFA sparing effects" of saturated fatty acids and monounsaturated fatty acids in fish feeds have been observed in many fish species. The present study was also aimed at validating the "n-3 LC-PUFA sparing effects" of saturated fatty acids and monounsaturated fatty acids in lard and Basa fish offal oil. Moreover, the effects of dietary lard and Basa fish offal oil on fish body composition and muscle quality were also evaluated. Lard (LD) and Basa fish offal oil (BFO) have similar fatty acid profiles, both containing high contents of saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA). The present study aimed to investigate the efficacy of partial or complete replacement of marine fish oil (MFO, herring oil) by LD or BFO in the diets of tiger puffer. The control diet contained 49.1% crude protein and 9.28% crude lipid content including 6% added MFO. In other diets, 1/3, 2/3, and 3/3 of the added MFO was replaced by LD or BFO, respectively. Each diet was fed to triplicate tanks of juvenile fish (initial body weight, 13.88 g). A 46-day feeding trial was conducted in a flow-through seawater system. Each diet was fed to triplicate 200-L rectangular polyethylene tanks, each of which was stocked with 30 fish. Fish were fed to satiation three times a day. The complete replacement of added MFO (replacing 65% of the total crude lipid) had no adverse effects on fish growth performance in terms of survival (>94%), weight gain (360–398%), feed intake (2.37–3.04%), feed conversion ratio (0.84–1.02), and somatic indices. The dietary LD or BFO supplementation also had marginal effects on fish body proximate composition, biochemical parameters, muscle texture, and water-holding ability, as well as the hepatic expression of lipid metabolism-related genes. Partial (2/3) replacement of added MFO by LD or BFO did not significantly reduce the muscle n-3 LC-PUFA content, indicating the n-3 LC-PUFA sparing effects of SFA and MUFA in LD and BFO. In general, dietary LD or BFO reduced the peroxidation level and led to significant changes in the muscle volatile flavor compound profile, which were probably attributed to the change in fatty acid composition. The results of this study evidenced that LD and BFO are good potential lipid sources for tiger puffer feeds. [ABSTRACT FROM AUTHOR]

With the advancement of internet of things and wireless sensing technology, the need for personnel track and position monitoring are greatly increasing. Commercial global positioning system (GPS) and Global system for mobile communications (GSM) position methods cannot meet the demand for low power consumption and three‐dimensional indoor position monitoring. Herein, a self‐powered position monitoring system (SPMS) based on an insole‐type wearable triboelectric nanogenerator (IW‐TENG) and Bluetooth beacon for human kinetic energy harvesting and sustainable position monitoring is proposed. The SPMS consists of an insole‐type wearable triboelectric nanogenerator, an energy management module (EMM), and a Bluetooth low energy (BLE) beacon module. Benefitting from the multilayers structure, a maximum energy of 120 µJ per step can be harvested by the IW‐TENG with EMM for a typical adult. By every 3–4 steps, SPMS can transmit Bluetooth signals to obtain the location information. A single BLE signal transmission consumes only 136 µJ, and the transmission distance can reach 100 m. The SPMS is applied to intelligent attendance in office rooms and shows great prospects in intelligent navigation and trajectory tracking in local area network. [ABSTRACT FROM AUTHOR]

Power management is an efficacious route to promote the development of triboelectric nanogenerators (TENGs), in which the buck switch for efficient energy extraction has always been a challenge. Here, we propose a three-port cantilever buck switch which can autonomously release energy from the TENG in maximum by the generated electrostatic field of the TENG. The influence of closing voltage of the buck switch on different structure parameters has been thoroughly investigated. The U-Q curve indicates that the optimal energy extraction can reach 90.86%, and the matched impedance of the TENG is reduced from 60 MΩ to 470 kΩ. Compared to the output power at matched impedance, the average power managed by this three-port cantilever buck switch is increased by 1.554 times, which can power the Bluetooth device, electronic watch, calculator and thermo-meter. This work has realized ultra-efficient power management of TENG by leveraging an autonomous cantilever buck switch, which can contribute to the efficient utilization of micromechanical energy. • A three-port cantilever buck switch controlled by the electrostatic field of the TENG for its power management is pioneered. • A detailed analysis of the force-electricity conversion process has been conducted. • U-Q curve and P-R curve has been linked to characterize the output efficiency for the first time. [ABSTRACT FROM AUTHOR]

[Display omitted] • A stretchable electret achieves high surface charge and long charge stability. • A stretchable electret-based TENG achieves high charge density (0.2 mC m−2). • A power management module enhances power storage efficiency of the TENG. • The self-charging system provides a stable power supply for wearable electronics. Stretchable power sources capable of accommodating large deformations are urgently demanded for various stretchable and wearable electronics. In this work, we report a stretchable electret-based triboelectric nanogenerator (SEB-TENG) consisting of elastomeric electret as electrification materials and organo-hydrogels as electrodes. The electret elastomer, prepared by uniformly dispersing SiO 2 nanoparticles in the elastomer matrix and thermally injecting static charges, obtains a high surface potential, high tensile strain (796%), and long stability. Then, the SEB-TENG device also achieves high stretchability (423%) and high charge density (0.2 mC m−2). Furthermore, a power management module (PMM) is designed to maximize the energy utilization of the SEB-TENG. The integrated self-charging system can be sufficiently used to constantly power a watch, or charge a Li-ion coin cell which subsequently provides sustainable power supplies to a digital thermometer. This work provides a viable approach to simultaneously achieve high output performances and high stretchability of integrated power sources. [ABSTRACT FROM AUTHOR]

The tribovoltaic effect can convert semiconductor interfacial frictional mechanical energy into direct current (DC) electricity, but the flexibility and durability of semiconductor materials limit its application in wearable electronic. Herein, a robust flexible textile tribovoltaic nanogenerator is presented based on a 2D dynamic heterojunction of 2H‐MoS2/Ta4C3 (MTNG). During the friction process, a built‐in electric field (Eb) and an additional interfacial electric field (ECE) are generated in a continuous dynamic contact of 2H‐MoS2/Ta4C3, and through the 2H‐MoS2/Ta4C3 dynamic heterojunction, a significant number of electron‐hole pairs are excited and move directionally to generate a DC. The influences of mechanical pressure and sliding speed on output performance of MTNGs are systematically investigated. The MTNGs deliver excellent output power density (39.15 mW m2) and outstanding robustness (43 000 cycles). Ten MTNGs can be connected in series to obtain a DC voltage of 3.3 V and in parallel to obtain a DC current of 75 µA. Furthermore, the MTNGs can effectively power a variety of commercial electronic watches and calculators by harvesting human kinetic energy. A 2D dynamic heterojunction 2H‐MoS2/Ta4C3 DC nanogenerator is described and offers a workable option for the creation of flexible DC power sources and self‐powered wearable electronics. [ABSTRACT FROM AUTHOR]

[Display omitted] • H-SiO 2 and PF as fillers to improve the dielectric properties of PFS films. • The performance of TENGs delivered an enhancement by 13 times. • Multiple nanoscales is more favorable to achieve high performance of TENGs. Triboelectric nanogenerators (TENGs), capable of harvesting distributed energy from the environment, have provided a viable solution for self-powered wearable electronics. However, their low power density and susceptibility to contamination still severely limit their practical application. Herein, we reported a "two-step" strategy to implement a waterproof self-powered wearable electronic device based on TENG. Firstly, Perfluoropolyether (PF) and hollow hierarchical silica (H-SiO 2) as fillers significantly improve the dielectric properties of polydimethylsiloxane (PDMS) composite films (PFS films) through polarization effect. Then the nano bumps of 10–30 nm are created on the surface of the films by surface etching, the bumps can increase the contact area of TENG. The voltage of TENG is improved from ∼ 67 V to ∼ 910 V and the current is improved from ∼ 1 μA to ∼ 25 μA. What's more, the investigation of the surface structure of the PFS composite films by Atomic Force Microscope (AFM) revealed that the synergistic combination of multiple nanoscales (10–30 nm, 60–80 nm, 300–500 nm) is more favorable to achieve high performance of TENG. The surface structure composed of multiple nanoscales endows PFS with excellent superhydrophobicity. The PFS films remained fine performance after 40,000 drops of water and 90 days. This work achieves high performance and water resistance of TENG, demonstrating great potential in the field of self-powered wearable electronic devices. [ABSTRACT FROM AUTHOR]

Based on the coupling effect of contact electrification and electrostatic induction, the triboelectric nanogenerator (TENG) as an emerging energy technology can effectively harvest mechanical energy from the ambient environment. However, due to its inherent property of large impedance, the TENG shows high voltage, low current and limited output power, which cannot satisfy the stable power supply requirements of conventional electronics. As the interface unit between the TENG and load devices, the power management circuit can perform significant functions of voltage and impedance conversion for efficient energy supply and storage. Here, a review of the recent progress of switching power management for TENGs is introduced. Firstly, the fundamentals of the TENG are briefly introduced. Secondly, according to the switch types, the existing power management methods are summarized and divided into four categories: travel switch, voltage trigger switch, transistor switch of discrete components and integrated circuit switch. The switch structure and power management principle of each type are reviewed in detail. Finally, the advantages and drawbacks of various switching power management circuits for TENGs are systematically summarized, and the challenges and development of further research are prospected. [ABSTRACT FROM AUTHOR]

The emerging tribovoltaic nanogenerators (TVNGs) has garnered considerable attention in recent years owing to its higher power density, but it is still limited by unstable output, mismatched impedance, and lower charging speed. Herein, a power‐managed GaN‐based TVNG is first proposed and a self‐powered wireless temperature monitoring system (SWTMS) is developed. The energy backflow from transition capacitor to TVNG is effectively suppressed by applying a high‐voltage‐resistant diode. Benefiting from the combination of the maximum power point tracking (MPPT and the buck converter, an autonomous power management unit (PMU) is designed. The internal impedance of TVNG with PMU decreases by ten times and the charging speed of capacitor increases by 7.18 times compared to those without PMU. Moreover, 100 LEDs and six parallel thermohygrometers can be constantly powered. The wireless temperature monitoring in industrial environments without external power supply is demonstrated through the developed SWTMS. This work proposes an effective power management strategy for TVNG with high output voltage, which exhibits great potential to promote the development of self‐powered sensors and Industrial Internet of Things (IIoT). [ABSTRACT FROM AUTHOR]

The tribovoltaic effect raises an emerging semiconductor energy technology and silicon‐based tribovoltaic nanogenerator (Si‐TVNG) has aroused great attentions. However, the electrical output of Si‐TVNG is extremely unstable due to its complicated mechanism. Here, a competitive mechanism between the built‐in electric field (BEF) and the interfacial electric field (IEF) is proposed to determine the current direction and magnitude of the Si‐TVNG. The results indicate that the natural oxide layer, load pressure, and resistivity of Si significantly affect the IEF and BEF. The natural oxide layer can store surface charges by contact electrification, resulting in a IEF dominant carriers transport process. Conversely, lower resistivity and higher load pressure can reduce the contact resistance, thereby decreasing the surface charges caused by contact electrification and leading to a BEF dominant carrier transport process. This work contributes to deeper understandings of the tribovoltaic effect and further clarifies the theoretical mechanisms of carrier excitation and directional transport. [ABSTRACT FROM AUTHOR]

A series of direct‐current tribovoltaic nanogenerators (TVNGs) with high current density have been developed for energy harvesting and mechanical sensing recently, but the lead wires that need to be connected to two relatively moving parts have greatly restricted the application of TVNG. Herein, a freestanding‐mode TVNG (FTVNG) is proposed based on metal, p‐type silicon (p‐Si), and n‐type silicon (n‐Si). As the freestanding part of metal simultaneously rubs against p‐Si and n‐Si, opposite direct current (DC) outputs can be generated, thus forming a DC output from p‐Si to n‐Si in the external circuit. Resulting from the distinctive structure, FTVNGs are applicable for harvesting energy from moving objects without attached wires. Additionally, by using steel needles to precisely control the actual contact area, the electrical output characteristics and influence laws of the tribovoltaic effect under different working parameters such as area and speed are studied. Moreover, FTVNG is integrated into the traditional rolling bearing as a triboelectric bearing, realizing energy recovery from the rotational motion of mechanical parts and speed sensing, which demonstrates the great application potential of TVNG in basic components and parts. [ABSTRACT FROM AUTHOR]

Highlights: A flexible tribotronic artificial synapse with bioinspired neurosensory behaviour was demonstrated, which establishes an active interaction mechanism with the environment. The device can well exhibit tuneable synaptic behaviours by changing the mechanical input modes, including excitatory postsynaptic current, paired-pulse facilitation, and the hierarchical memorial process. The device has excellent mechanical flexibility that can exhibit stable synaptic functions even under strain conditions with a bending radius of 20 mm after 1000 bending cycles. As key components of artificial afferent nervous systems, synaptic devices can mimic the physiological synaptic behaviors, which have attracted extensive attentions. Here, a flexible tribotronic artificial synapse (TAS) with bioinspired neurosensory behavior is developed. The triboelectric potential generated by the external contact electrification is used as the ion-gel-gate voltage of the organic thin film transistor, which can tune the carriers transport through the migration/accumulation of ions. The TAS successfully demonstrates a series of synaptic behaviors by external stimuli, such as excitatory postsynaptic current, paired-pulse facilitation, and the hierarchical memory process from sensory memory to short-term memory and long-term memory. Moreover, the synaptic behaviors remained stable under the strain condition with a bending radius of 20 mm, and the TAS still exhibits excellent durability after 1000 bending cycles. Finally, Pavlovian conditioning has been successfully mimicked by applying force and vibration as food and bell, respectively. This work demonstrates a bioinspired flexible artificial synapse that will help to facilitate the development of artificial afferent nervous systems, which is great significance to the practical application of artificial limbs, robotics, and bionics in future. [ABSTRACT FROM AUTHOR]

With the extensive application of wireless sensing nodes, the demand for sustainable energy in unattended environments is increasing. Here, we report a self-powered and autonomous vibrational wake-up system (SAVWS) based on triboelectric nanogenerators and micro-electromechanical system (MEMS) switches. The energy triboelectric nanogenerator (E-TENG) harvests vibration energy to power the wireless transmitter through a MEMS switch. The signal triboelectric nanogenerator (S-TENG) controls the state of the MEMS switch as a self-powered accelerometer and shows good linearity in the acceleration range of 1–4.5 m/s2 at 30 Hz with a sensitivity of about 14.6 V/(m/s2). When the acceleration increases, the S-TENG turns on the MEMS switch, and the wireless transmitter transmits an alarm signal with the energy from E-TENG, using only 0.64 mJ. Using TENGs simultaneously as an energy source and a sensor, the SAVWS provides a self-powered vibration monitoring solution for unattended environments and shows extensive applications and great promise in smart factories, autonomous driving, and the Internet of Things. [ABSTRACT FROM AUTHOR]

Highly efficient, all-solution processed inverted quantum dot light-emitting diodes (QLEDs) are demonstrated by employing 1,3,5-tri(m-pyrid-3-yl-phenyl)benzene (TmPyPB) layer as electron blocking layer. Electron injection from ZnO electron transport layer to quantum dots (QDs) emission layer (EML) can be adjusted by thickness of TmPyPB layer, enabling the balanced charge carriers in QDs EML. With optimal thickness of this TmPyPB adjuster, 59.7% increment in the device current efficiency (from 8.2 to 13.1 cd A−1) and 46.2% improvement in the maximum luminance (from 31916 to 46674 cd m−2) are achieved, compared with those of the control QLED which has double hole transport layer structure. On the other hand, we find luminescence quenching process, which often happens at the interface of ZnO nanoparticles and QDs, is not obvious in our QLEDs, in which the ZnO layer is fabricated in precursor method, and this conclusion is verified through Time Resolution Photoluminescence test. In a word, this strategy provides a direction for optimizing charge carrier balance in all-solution processed inverted QLED. [ABSTRACT FROM AUTHOR]

A compact, springless, easy-to-process kirigami-inspired TENG (KI-TENG) is developed. The frequency responses of the KI-TENG under the influence of mass, acceleration, and initial distance are investigated in detail to optimize its structural design. Moreover, the TENG coupled with the kirigami structure could collect ultra-wide-band vibration energy and as a sensor measuring acceleration. [Display omitted] • A compact and springless kirigami-inspired TENG (KI-TENG) is developed. • The frequency response characteristics of the KI-TENG are investigated. • The KI-TENG can harvest ultra-wide-band vibration energy from 2 to 49 Hz. • The output of the KI-TENG at different vibration tilt angles is explored. • The KI-TENG can effectively monitor acceleration changes from 1 to 9 m/s2. Triboelectric Nanogenerators (TENGs) based on spring-assisted structures play a central role in scavenging vibrational energy that is widely available in the natural environment. However, they suffer from difficulties in adjusting the stiffness and bonding the springs to the triboelectric layer. Here, a kirigami-inspired TENG (KI-TENG) with a kirigami structure is demonstrated, which can be used as an ultra-wide-band vibrational energy harvester and self-powered acceleration sensor. The triboelectric layer of the KI-TENG can be easily processed into the kirigami structure with one or two-degree-of-freedom by laser cutting technology. The frequency responses of the KI-TENG under the influence of mass, acceleration, and initial distance are investigated in detail to optimize the structural design. With optimized structural parameters, the KI-TENG can not only harvest broadband vibration energy from 2 to 49 Hz in vertical vibration state but also obtain high output performance over a wide frequency range in horizontal vibration state. Moreover, the KI-TENG can be used as a sensor measuring acceleration from 1 to 9 m/s2. This work demonstrates a compact TENG coupled with the kirigami structure for energy harvesting and active sensing, which has great prospects in intelligent plants, artificial intelligence, and the internet age. [ABSTRACT FROM AUTHOR]

The wearable tactile sensors have attracted great attention in the fields of intelligent robots, healthcare monitors and human-machine interactions. To create active tactile sensors that can directly generate electrical signals in response to stimuli from the surrounding environment is of great significance. Triboelectric nanogenerators (TENGs) have the advantages of high sensitivity, fast response speed and low cost that can convert any type of mechanical motion in the surrounding environment into electrical signals, which provides an effective strategy to design the self-powered active tactile sensors. Here, an overview of the development in TENGs as tactile stimulators for multifunctional sensing and artificial synapses is systematically introduced. Firstly, the applications of TENGs as tactile stimulators in pressure, temperature, proximity sensing, and object recognition are introduced in detail. Then, the research progress of TENGs as tactile stimulators for artificial synapses is emphatically introduced, which is mainly reflected in the electrolyte-gate synaptic transistors, optoelectronic synaptic transistors, floating-gate synaptic transistors, reduced graphene oxides-based artificial synapse, and integrated circuit-based artificial synapse and nervous systems. Finally, the challenges of TENGs as tactile stimulators for multifunctional sensing and artificial synapses in practical applications are summarized, and the future development prospects are expected. [ABSTRACT FROM AUTHOR]

The use of renewable resources to generate energy is one of the most important policy goals in the energy sector. One method to use renewable resources is to apply integrated systems. In this study, an optimal multi-objective integrated system has been applied to power generation. The proposed system includes wind turbines, hydroelectric power plants, and photovoltaic systems. To achieve maximum power generation with minimum fluctuations, a Developed Owl search algorithm (DOSA) with three pareto front solutions has been used. Also, the efficiency of the integrated system in different climate conditions is evaluated. The results of the pareto front show that the developed owl search algorithm is the closest algorithm to the pareto front. Therefore, it is the most accurate to improve the overall multi-objective integrated system. Among pareto front solutions, the second solution provides acceptable results for increasing power generation and reduction of fluctuations. Also, the results of the evaluation of the efficient integrated system in different climate conditions show that in wet conditions when solar radiation and wind are reduced, hydropower causes current to continue in the system by generating electricity and compensating for wind and PV energy loss. • A wind-photovoltaic-hydropower hybrid system has been used. • The Developed Owl search algorithm is used to improve efficiency of the system. • Three climatic conditions are used to analyze the efficiency of the hybrid system. • The system can continue to generate power well in different climate. [ABSTRACT FROM AUTHOR]