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In recent years, the automotive industry has made significant progress in integrating multifunctional sensors to improve vehicle performance, safety, and efficiency. As the number of integrated sensors keeps increasing, there is a growing interest in alternative energy sources. Specifically, self‐powered sensor systems based on energy harvesting are drawing much attention, with a main focus on sustainability and reducing reliance on typical batteries. This paper demonstrates the use of triboelectric nanogenerators (TENGs) in a computer mouse for efficient energy harvesting and in automobile braking systems for safety applications using SrBi2Ta2O9 (SBTO) perovskite, blended PDMS composite operating in free‐standing mode with an interdigitated patterned aluminum electrode. This self‐powered sensor is capable of distinguishing between normal and abnormal braking patterns using digital signal processing techniques. It is noteworthy that the addition of 15% wt. of the SBTO in PDMS composite‐based TENG delivered 13.5 V, 45 nA, and an output power of 0.98 µW. This new combination of energy harvesting and safety applications enables real‐time monitoring and predictive maintenance in the automotive industry. [ABSTRACT FROM AUTHOR]

Bismuth sulfide (Bi2S3) is a chalcogenide semiconductor with a relatively narrow energy band gap that is promising for use in solar cells and photodetectors. This paper presents a highly efficient microwave synthesis of Bi2S3 submicrometric structures using poly(vinyl alcohol) (PVA) as a viscosity modification agent. The chemical composition, morphology, crystal structure, and optical properties of the prepared materials were investigated using transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, and diffuse reflectance spectroscopy (DRS). The use of PVA in Bi2S3 synthesis resulted in a change in material morphology from microrods to nanosheets and a slight increase in the energy band gap from 1.34 eV to 1.43 eV. The Bi2S3 nanosheets were examined as photosensitive materials for the detection of visible light. High ON/OFF ratios of 66, 44, and 15 and large specific detectivities of 1.12 × 1011, 7.68 × 1010, and 6.43 × 1010 Jones were achieved under blue (468 nm, 0.52 μW cm−2), green (517 nm, 0.95 μW cm−2), and red (628 nm, 0.13 μW cm−2) light illuminations, respectively. The photosensitive properties of Bi2S3 nanosheets were remarkable compared to that of many other photodetectors based on Bi2S3 micro- and nanostructures. [ABSTRACT FROM AUTHOR]

The present research offers an innovative approach to enhance the safety and mobility of people with visual impairments by using a smart white cane sensor. Herein, an aluminum electrode, Kapton film, and an inexpensive PET substrate are employed to develop an origami‐shaped multilayered triboelectric nanogenerator (TENG) device. The multilayered integration of three‐unit TENGs produces output with a high power of 51 μW at 50 MΩ, along with 155 V and 4.5 μA. Capacitor charging, low‐power electronics powering, and the integration of mechanoluminescent materials are demonstrated. The integration of mechanoluminescent materials enables efficient identification of visually impaired people in regions with poor lighting. A single‐electrode TENG is also implemented for successful surface material detection. To further enhance the sensor's capabilities, digital signal processing techniques are employed for obstacle recognition on their route. The intelligent white cane sensor effectively detects obstructions, offering the user instantaneous feedback and enabling more secure navigation in sophisticated environments. This study highlights the possibility of integrating TENG technologies to provide a complete solution for people with visual impairments. The smart white cane sensor has the potential to greatly increase the safety and independence of visually impaired people in a variety of outdoor and public spaces. [ABSTRACT FROM AUTHOR]

In recent years, there has been a surge in interest surrounding the development of chitosan (CS)-based triboelectric nanogenerators (TENG) for powering attachable/portable devices. Despite numerous strategies aimed at enhancing their efficiency, the selection of acid solvent has remained largely unexplored. In this study, various acids, including acetic (CH3COOH), succinic (C4H6O4), and citric (C6H8O7) acids, were investigated for their impact on mechanical and electrical output signals. Remarkably, the choice and concentration of acid were found to significantly influence performance. Specifically, employing citric acid rendered the CS solid film more pliable and yielded the highest output signal at optimal concentration levels. Under optimized conditions, the CS-TENG exhibited an open-circuit voltage output (VOC) of 157 V and short-circuit current output (ISC) of 53 µA—more than triple that of pristine CS-TENG. Mechanistic insights into electrical generation have been elucidated, underscoring the importance of solvent selection in CS TENG fabrication. These findings underscore the potential for tailored acid solvent selection to advance specialized applications in the field. [ABSTRACT FROM AUTHOR]

The rapid growth of global energy consumption and the increasing demand for sustainable and renewable energy sources have urged vast research into harnessing energy from various sources. Among them, the most promising approaches are nanogenerators (NGs) and solar cells (SCs), which independently offer innovative solutions for energy harvesting. This review paper presents a comprehensive analysis of the integration of NGs and SCs, exploring advanced hybrid structures and their diverse applications. First, an overview of the principles and working mechanisms of NGs and SCs is provided for seamless hybrid integrations. Then, various design strategies are discussed, such as piezoelectric and triboelectric NGs with different types of SCs. Finally, a wide range of applications are explored that benefit from the synergistic integration of NGs and SCs, including self‐powered electronics, wearable devices, environmental monitoring, and wireless sensor networks. The potential for these hybrid systems is highlighted to address real‐world energy needs and contribute to developing sustainable and self‐sufficient technologies. In conclusion, this review provides valuable insights into the state‐of‐the‐art developments in NGs and SCs integration, shedding light on advanced hybrid structures and their diverse applications. [ABSTRACT FROM AUTHOR]

This study presents a novel approach utilizing solvothermal techniques to synthesize zeolitic imidazolate framework (ZIF‐4) particles. Various properties of the ZIF‐4 particles are investigated to shed light on the structural and morphological characteristics. These ZIF‐4 particles act as a positive triboelectric layer in the fabrication of a triboelectric nanogenerator (TENG) designed for powering electronic devices. The solvothermal‐assisted synthesis ensures the controlled and efficient production of ZIF‐4, optimizing its characteristics for enhanced performance in the TENG. The generated TENG, based on ZIF‐4 particles, determines promising capabilities in converting mechanical energy into electrical power. The highest power of TENG is obtained to be 18 μW at a load resistance of 50 MΩ. This work contributes major insights to the search for sustainable and effective power solutions for electronic gadgets. It emphasizes the potential of ZIF‐4 as a crucial triboelectric material, demonstrating its importance in the advancement of TENGs. [ABSTRACT FROM AUTHOR]

The ferroelectric‐semiconductor behavior of antimony sulfoiodide (SbSI) has opened up the material as a base for energy‐harvesting devices. Specifically, SbSI has drawn much attention for pyroelectric energy harvesting and thermal sensing with outstanding electrothermal properties. This work investigates the thermistor properties of an SbSI material and presents the development of an SbSI nanorod/Kapton‐based triboelectric nanogenerator (TENG) for effective energy harvesting and temperature sensing. The TENG based on SbSI/ Kapton operating in vertical contact separation mode delivers a peak‐to‐peak voltage of 90 V and a current of 1510 nA, respectively. Introducing SbSI nanorods for TENG opens the possibility of extending the conventional triboelectric series. The electrical and dielectric properties of the SbSI nanorods are investigated. SbSI exhibits a highly linear temperature coefficient of resistance (TCR) of −0.026 °C−1, making it an excellent candidate material for a thermistor. In addition, the material exhibits an excellent thermal sensitivity (β20/80 = 1612.1 K). For demonstration, the SbSI thermistor is connected with TENG, and the outputs at various temperatures are analyzed for self‐powered temperature sensing. This capability allows for efficient temperature monitoring without relying on external power sources, advancing remote, and autonomous sensing applications. [ABSTRACT FROM AUTHOR]

Battery-free and biodegradable sensors can detect biological elements in remote areas. The triboelectric nanogenerator (TENG) can potentially eliminate the need for a battery by simply converting the abundant vibrations from nature or human motion into electricity. A biodegradable sensor system integrated with TENG to detect commonly found disease-causing bacteria (E. coli) in the environment is showcased herein. In this system, D -mannose functionalized 3D printed polylactic acid (PLA) with the brush-painted silver electrode was used to detect E. coli by a simple carbohydrate–protein interaction mechanism. The adsorption capacity of D -mannose is generally altered by varying the concentration of E. coli resulting in changes in resistance. Thus, the presented biosensor can detect bacterial concentrations by monitoring the output current. The PLA TENG generates an output of 70 V, 800 nA, and 22 nC, respectively. In addition, tap water and unpasteurized milk samples are tested for detecting bacteria, and the output is measured at 6 μA and 5 μA, respectively. Further, the biosensor was tested for biodegradability in soil compost by maintaining constant temperature and humidity. This study not only proposes an efficient and fast method for screening E. coli but also gives important insights into the ability to degrade and long-term reliability of TENG-based sensor platforms. [ABSTRACT FROM AUTHOR]

The spent catalysts discarded during chemical manufacturing can be a source of pollution and are classified as hazardous waste. Looking at the bright sides of the mission of waste management, such as recycling and reducing, reuse such types of the spent catalyst can be chemically treated to extract valuable salts and metals. Such a process not only reduces waste disposal issues but also promotes a circular economy ecosystem. This present study aims to extract MoO3 from the spent petroleum catalyst, Mo–Ni/Al2O3, and further processing of Mo‐metal organic framework (MOF) particles using extracted MoO3 and imidazole acting as an organic binder. The structural, morphology, and thermal properties of Mo‐MOF are evaluated. The surface roughness and positive surface potential of the Mo‐MOF are achieved. The Mo‐MOF/Kapton‐based triboelectric nanogenerators (TENG) generate a 148 V voltage, 470 nA current, and 17 nC charge. Further, TENG is utilized to charge the capacitors, and powering of the electronic devices is demonstrated. The repetition of the boxing punches and exercises can be monitored using TENGs and paves the way toward intelligent sports or healthcare. [ABSTRACT FROM AUTHOR]

The development of triboelectric nanogenerators (TENGs) has experienced rapid advancement in the past decade. In the present study, ethylene vinyl acetate (EVA) polymer and lead zirconium titanate (PZT) are taken as the host materials. The EVA–PZT elastomer composites are fabricated using different weight percentages (2.5%, 5.0%, 7.5%, and 10.0%) of PZT in EVA by solvent casting. The X‐ray diffraction investigation of these films reveals the presence of the PZT material and the formation of composites. TENGs have the potential to revolutionize energy harvesting and provide a sustainable energy source for a variety of applications. The electrical output performance of the single‐electrode‐mode‐based TENG is examined. The maximum output of 60 V and 165 nA is produced by the EVA–PZT 7.5 wt%/Al‐based TENG device. Further, TENG is used to power devices and gather biomechanical energy. [ABSTRACT FROM AUTHOR]

Mechanical metamaterials are attracting considerable attention due to their unique properties not found in natural materials. Advanced geometrical shapes such as Menger cubes, origami templates, and gyroids offer exciting avenues for device engineering. In addition, the recent developments of various additive manufacturing technologies have expanded materials selection and geometrical complexities. Herein, a piezoresistive pressure sensor based on a 3D‐printed gyroid structure with a conformal coating of carbon nanotubes (CNTs) is presented. The gyroid structures are printed using fused deposition modeling (FDM) 3D printing with thermoplastic polyurethane (TPU), providing mechanical robustness even at low densities. By altering the relative density of the gyroid structure, Young's modulus can be tailored, ranging from 0.32 MPa at 30% relative density and 3.61 MPa at 80% relative density. The presented gyroid‐based pressure sensor achieves a wide sensing range of up to 1.45 MPa and a high sensitivity of 2.68 MPa−1. The sensor is integrated into a shoe for wearable applications, demonstrating its mechanical robustness and potential for human stance and motion monitoring. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) are gaining attention for energy supply because of higher demands in decentralized energy production. TENGs are known for being self-energy harvesters, converting wasted mechanical energy to useful electrical energy under an ambient environment. Advantages of TENGs include a clean energy supply, a wide range of materials selection, and an energy scavenging capability in the ambient environment. However, TENGs still suffer from their low electrical outputs compared to existing electrical supplies such as fuel cells and batteries. In bio-photovoltaic (BPV), there has been an interest in the use of microalgae, which are photosynthetic microorganisms capable of carbon capture and generating bioelectricity both day and night through electron transport chains via photosynthesis and cell respiration. To increase the current output of BPV, many have tried to immobilize living microalgal cells onto electrodes for higher mass transfers leading to higher photosynthetic rates. In this study, we have used immobilized living microalgae (Chlorella sp.) onto aluminium sheets to fabricate the TENG systems and investigate biomechanical energy harvesting. This proof of concept shows that this integration of microalgae with TENG can enhance the voltage and current output achieved by the dual operation modes of TENG. One issue raised during the tests was maintaining microalgae alive for several days, which has given opportunities for further studies in nutrient and light supplies to this innovative sustainable hybrid technology. The results confirm that the microalgae can be an excellent triboelectric layer in TENG for biomechanical energy harvesting. [ABSTRACT FROM AUTHOR]

The nanorods of bismuth sulfoiodide (BiSI) were synthesized at relatively low temperature (393 K) through a wet chemical method. The crystalline one-dimensional (1D) structure of the BiSI nanorods was confirmed using high resolution transmission microscopy (HRTEM). The morphology and chemical composition of the material were examined by applying scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS), respectively. The average diameter of 126(3) nm and length of 1.9(1) µm of the BiSI nanorods were determined. X-ray diffraction (XRD) revealed that prepared material consists of a major orthorhombic BiSI phase (87%) and a minor amount of hexagonal Bi13S18I2 phase (13%) with no presence of other residual phases. The direct energy band gap of 1.67(1) eV was determined for BiSI film using diffuse reflectance spectroscopy (DRS). Two types of photodetectors were constructed from BiSI nanorods. The first one was traditional photoconductive device based on BiSI film on stiff glass substrate equipped with Au electrodes. An influence of light intensity on photocurrent response to monochromatic light (λ = 488 nm) illumination was studied at a constant bias voltage. The novel flexible photo-chargeable device was the second type of prepared photodetectors. It consisted of BiSI film and gel electrolyte layer sandwiched between polyethylene terephthalate (PET) substrates coated with indium tin oxide (ITO) electrodes. The flexible self-powered BiSI photodetector exhibited open-circuit photovoltage of 68 mV and short-circuit photocurrent density of 0.11 nA/cm2 under light illumination with intensity of 0.127 W/cm2. These results confirmed high potential of BiSI nanorods for use in self-powered photodetectors and photo-chargeable capacitors. [ABSTRACT FROM AUTHOR]

Perovskites are of significant interest in the field of photocatalysis. To date, many perovskite nanostructures have been developed, and their applications in photocatalysis have been studied. There has been considerable improvement in the research on metal doping in the perovskite structure to improve their optical and structural properties. This mini-review examines the recent progress in the synthesis of lead-free double perovskite nanoparticles and their application in visible-light photocatalysis. Lead-free perovskites are emerging as an eco-friendly solution in energy, electrochemistry, and sensing. Double perovskites are known for their flexible structural, optical, and morphological properties due to their lattice framework having a general form AAʹBBʹO6. They are more useful for hydrogen evolution due to their higher conduction band potential than simple perovskites. Here, we summarize the current progress and provide insights for the future development of double perovskites toward efficient photodegradation. [ABSTRACT FROM AUTHOR]

Soft robotics enables various applications in certain environments where conventional rigid robotics cannot deliver the same performance due to their form factor and stiffness. Animals use their soft external organs to carry out activities in response to challenging natural environments efficiently. The objective of soft robots is to provide biologically inspired abilities and enable adaptable and flexible interactions with complex objects and surroundings. Recent advances in stimuli-responsive soft robot technology have heavily used polymer-based multifunctional materials. Soft robots with incredibly sophisticated multi-mechanical, electrical, or optical capabilities have demonstrated the ability to modify their shape intelligently in response to external stimuli, such as light, electricity, thermal gradient, and magnetic fields. This short review covers recent advances in scientific techniques for incorporating multifunctional polymeric materials into stimuli-responsive bioinspired soft robots and their applications. We also discuss how biological inspiration and environmental effects can provide a viable viewpoint for bioinspired design in the innovative field of soft robotics. Lastly, we highlight the future outlooks and prospects for soft, stimuli-responsive, bio-inspired robots. [ABSTRACT FROM AUTHOR]

Multiferroics particles with the chemical formula of FeTiVO6 (FTVO) were synthesized using a solid-state reaction and blended with PDMS to obtain flexible composites. The FTVO particles crystallize in orthorhombic symmetry, and the multiferroic nature was confirmed using room temperature M-H and P-E hysteresis loops. A triboelectric nanogenerator (TENG) device was prepared using the composite at different wt% of FTVO-PDMS as a triboelectric layer. To enhance the output performance of TENG, microroughness composites were prepared following a cost-effective route. The 5 wt% of FTVO in the PDMS composite-based device delivered a higher electrical output of 110 V, 0.8 µA, and power of 65 µW at 108 Ω. The demonstration of charging capacitors confirms that the TENG can act as a sustainable power source. The long-term stability of the device output confirms that fabricated TENG can be utilized as self-powered sensors. Humidity is a factor that limits the performance of the TENG. The packing of the TENG could solve this problem by stopping the interaction of triboelectric layers with moisture and humidity. Hence, demonstration of the packed TENG under harsh conditions such as inside the water tub and at varying humidity levels was carried out to confirm the stability of the output. [ABSTRACT FROM AUTHOR]

The energy crisis and depletion of non-renewable energy resources have been aggravated due to the drastic rise in world pollution and the energy demand. Facile hydrogen production through water splitting has become a popular alternative source of energy owing to the numerous environmentally friendly and economic benefits it provides. Additionally, it is preferred due to the depletion of non-renewable energy resources, pollution caused by the burning of non-renewable energy resources, and climate change. Hydrogen is generated from water and acts as a clean energy without contributing to carbon emissions. Various water-splitting methods such as electrolysis, thermochemical, mechanocatalysis, plasmolysis, photocatalysis, and photoelectrocatalysis can be applied to obtain hydrogen and oxygen. This review highlights the multifunctional materials used in photo-electrochemical water splitting and their superior properties for producing carbon-free energy from water. Multifunctional materials help reduce aqueous protons to hydrogen and oxidize water to oxygen during the splitting of water. This paper discusses a wide class of materials such as carbon materials, metal–organic frameworks, perovskites, and semiconducting oxides for efficient hydrogen production. Different types of water-splitting methods and multifunctional materials with varying properties can lead to improved results. The review sheds light upon the hydrogen economy and future prospects, elucidating the selection of multifunctional materials for efficient hydrogen production. [ABSTRACT FROM AUTHOR]

Cobalt ferrite bearing the chemical formula of CoFe2O4 was synthesized by a high-temperature solid-state reaction. The Rietveld refinement of the experimental XRD data shows that the synthesized material crystallizes in a cubic symmetry with a lattice parameter a = b = c = 8.391 Å. The magnetic property of CoFe2O4 reveals the maximum magnetization value of 84.17 emu/g, confirming a strong ferrimagnetic nature. Further, we have built an electromagnetic energy generator (EMG) device based on the CoFe2O4 magnetic material, copper coil, and three-dimensional (3D) printed tube-like structure. The electrical output response of the device was collected by shaking it by hand and an electric shaker. A voltage of 1.95 V and current of 4.7 mA was generated from the device while delivering a power output as high as 0.86 mW at a load resistance of 103 Ω. The electrical output remained constant over long-term device operation, confirming that the fabricated device is capable of generating a stable output for a longer duration. Powering of light-emitting diodes (LEDs) and charging of capacitors were performed by utilizing the fabricated EMG. Further, the self-powered recognition of different speeds when the device was placed upon an electric shaker confirms that it can be utilized in many real-time applications. [ABSTRACT FROM AUTHOR]

Harvesting mechanical energy from the surroundings can be a promising power source for micro/nanodevices. The triboelectric nanogenerator (TENG) works on the principle of triboelectrification and electrostatic induction. So far, metals and polymers have mostly dominated the conventional triboelectric series, but there is a need to find novel materials to extend the triboelectric series and further improve the performance of a TENG. Herein, a zeolitic imidazole framework (ZIF-67) was synthesized using a room temperature solvent-assisted route. Extensive material analysis was performed to understand its structural and chemical properties. Further, a simple vertical contact mode S-shaped TENG device (abbreviated further as S-TENG) was fabricated using an additive manufacturing approach. ZIF-67 acted as a positive triboelectric layer while Teflon/PDMS acted as a negative triboelectric layer. The multi-unit S-TENG device was further utilized for self-powered recognition of the various gaits using a digital signal processing approach. The S-TENG device based on ZIF-67 and Teflon produced a voltage of 118 V, a current of 1.7 mA, and a power density of 15 mW cm2 at a load resistance of 50 MO. The gait analysis of different volunteers was recorded by employing the S-TENG device and the digital signal processing route to effectively distinguish the gait patterns for the prevention of falls and injury. The S-TENG device was utilized to charge a commercial capacitor for powering a wristwatch and further it was attached to a robotic gripper for object identification. [ABSTRACT FROM AUTHOR]

The gas-sensing equipment experienced a greater demand in different workplace environments owing to its high capability to detect the unburnt poisonous gases in the boilers or analyzing the airborne pollution levels. The recent trend toward achieving an efficient gas sensor depends on the low-power consumption and miniaturization. In addition, emerging nanomaterials have shown great potential toward gas sensing along with their outstanding electrochemical properties. This work aims toward the sensing of hydrogen gas utilizing carbon nanotubes (CNTs) directly integrated onto a Pt microheater. The pristine CNTs detect hydrogen gas through the change in the electrical resistance. The chemical reaction between the hydrogen molecule and CNTs is promoted at high temperatures by utilizing the microheater. The suggested spray-coated CNT layer survives subsequent microfabrication processes, demonstrating a robust integration method of nanomaterials into conventional microelectromechanical systems (MEMS). CNTs integrated Pt microheater is batch fabricated using a microfabrication technique, allowing a high device yield of over 90%. The fabricated gas sensors demonstrate a low power budget of a few mW and owe a fast response time. The temperature is elevated up to 420 °C by supplying 2.19 mW power for gas sensing, and the change in the rate of resistance change reached 1.82% by supplying hydrogen gas of 10% concentration. The response and recovery time from the microheater are found to be 39 and 35 seconds, respectively. Besides, the decrease in drift factor occurs when the sensor operates at too high temperatures. The gas concentration is controlled and simultaneously the rate of resistance change is evaluated which further helps to obtain a LOD value of 1200 ppm. The Raman spectra of CNTs before and after the gas-sensing experiment confirm that there is no change or degradation of the CNTs during the experimental process. The fabricated CNTs integrated Pt microheater-based gas sensor has immense potential toward sensing hydrogen gas. [ABSTRACT FROM AUTHOR]

The naturally available cyclodextrin has opened up a wide range of research avenues because of its superior characteristics such as being non‐toxic, biocompatible, and edible. The cyclodextrin is the green multifunctional material that can add to the triboelectric series and extend its self‐powered applications. The ultrasonic synthesized cyclodextrin metal–organic framework (CD‐MOF) designed using sodium as a metal ion and cyclodextrin as a ligand for the triboelectric nanogenerator is reported. The various detailed characterizations of the CD‐MOFs give an insight into the properties of the synthesized material. The Kelvin probe force microscopy suggests three types of CD‐MOFs, exhibiting a positive potential. As per the surface potential, the output of the various CD‐MOF based TENG is varied as alpha CD MOF/Teflon > gamma CD‐MOF/Teflon > beta CD‐MOF/Teflon. The alpha CD MOF/Teflon TENG produces an electrical output of 152 V, 1.2 μA, and 14.3 nC, respectively. The fabricated device output is utilized for powering numerous low‐power electronics through a capacitor and bridge rectifier circuit. The multiunit Z‐shaped TENG device is attached to various surfaces such as the shoe heel and the backside of the school bag, and the corresponding energy harvesting response is demonstrated. [ABSTRACT FROM AUTHOR]

In this paper, for the first time, electroactivated disposable pencil graphite electrode (ePGE) was used for the detection of bioflavonoid hesperidin with cyclic and differential pulse voltammetry. The electroactivation efficiency of the pencil graphite electrode (PGE) was examined employing electrochemical impedance spectroscopy (EIS) and scanning electrochemical microscopy (SECM) and the enhancement of electron transfer kinetics of the PGE after the electroactivation was found. Hesperidin is irreversibly oxidized on the ePGE and its oxidation was the most pronounced at pH=5.0. Two electrode processes were detected, on one hand, a mixed diffusion and adsorption control was observed for the first electrode process. On the other hand, only diffusion control was observed in the second electrode process. Linear dependence between the peak current and the hesperidin concentration was obtained in the concentration range from 5×10−7 mol dm−3 to 1×10−5 mol dm−3 and the determined lower limit of detection (LOD) was 2×10−7 mol dm−3. Moreover, hesperidin in pharmaceutical formulation (containing active substance, hesperidin, and excipients) was quantified using ePGE. A good correlation was obtained between experimentally obtained hesperidin concentration by voltammetric analysis and concentration determined by standard HPLC technique (R2=0.9462). [ABSTRACT FROM AUTHOR]

In the present era, global challenges are focused to meet the security of energy due to excessive energy demands. The coal and petroleum-based fossil fuels are soon fading out due to current energy-generating units; hence, the energy from renewable energy sources becomes an alternative medium and new scientific investment. Research is carried out to boost the efficiency of these devices. The multifunctional materials having superior properties are the need of the hour to provide insight towards producing low-cost energy devices. A perovskite having the chemical formula Bi1/2(Na1/4Li1/4)TiO3 (BNLTO) is synthesized using a solid-state reaction. The standard techniques were used to investigate the structural and electrical characterizations at various experimental conditions. The X-ray diffraction (XRD) spectra elucidated the presence of an orthorhombic symmetry in the synthesized sample. The high dielectric constant and low loss factor is evolved at various frequencies and temperatures. The Nyquist plot depicts the association of the combined effect of grain and grain boundary. The activation energies evaluated from the loss and modulus spectrum are noted as ~ 1.26 eV and 0.81 eV, respectively. The charge carriers contribute to the conduction mechanism at high temperature. Finally, a poled piezoelectric energy harvester is fabricated to check its capabilities for the conversion of small impact from hand palm into electrical energy. [ABSTRACT FROM AUTHOR]

The switchable dipole moments and high piezoelectric coefficients in ferroelectric materials are the state-of-the-art used in piezoelectric energy harvesting. Hybridizing the triboelectric (TENG) and piezoelectric (PNG) shows great potential in harvesting the biomechanical energy by utilizing the ferroelectric dipoles embedded within the polymer. Unlike most of the previous approach to increase hybrid output by the external configuration of piezoelectric and triboelectric between two contact surfaces, in this paper, the output performance is significantly enhanced by improving the output performance of TENG by introducing a ferroelectric (Ba0.85Ca0.15)(Ti0.90Zr0.10)O3−x BiHoO3 (x = 0.02, 0.04, 0.06, 0.08, 0.1) (BCZTBH termed further) particles in PDMS which acts as a negative triboelectric layer. The structural and piezoelectric properties of BCZTBH particles are correlated in this report with the necessary characterization techniques. The systematic study of integrating single unit hybrid generator (S-HG) in a stacked manner paves the way to develop cost-effective, highly efficient ferroelectric films for utilization in the next-generation energy harvesting. The performance of the device is boosted by adopting a multi-stack configuration by designing a multi-stack hybrid generator (MS-HG) that could generate an electrical output of 300 V and a power density of 157 mW m−2 upon mechanical excitations. Further, enhanced and reliable performance of the MS-HG is demonstrated as a proof of application by effectively integrating a capacitor, infrared transmitter and receiver into a self-powered wireless infrared communication module and body activity counter/monitoring. [ABSTRACT FROM AUTHOR]

This paper presents the fabrication and electrical characterization of a lead-free polycrystalline complex electronic material Ba0.8Sr0.2(Zr0.1Ti0.8Ce0.1)O3 (abbreviated as BSZTCO) using standard experimental techniques. The phase identification of the material, determined using X-ray diffraction data, depicts the formation of a multi-phase system. The various electrical parameters were obtained at different frequencies (102–106 Hz) and temperatures (20–500 °C) using the phase-sensitive meter and found interesting results. Study of the micrograph of natural surfaces of the sample suggests that the ceramic sample has been formed with high density grain growth (without any cracks or voids). The transport properties and dielectric relaxation characteristics of the material have been studied using modulus and impedance spectroscopy techniques. Temperature dependence of conduction behavior (Nyquist plot) confirms the presence of bulk and grain boundary effects in the material. The charge transfer by hopping dominates the electrical transport process of the material as revealed from conductivity analysis. The dielectric relaxation of the material is studied using a complex modulus spectrum depicting non-Debye type relaxation. [ABSTRACT FROM AUTHOR]

The strontium-modified barium titanate ( Ba 0. 7 Sr 0. 3 TiO 3) ceramic was fabricated by high temperature compound reaction route. The pattern of X-ray diffraction confirms a single-phase compound with better crystallization. The dielectric properties (permittivity/loss) are investigated as a function of temperature and frequency. The relaxation mechanism and correlation with the physical properties are studied using complex impedance spectroscopy. The Nyquist plot shows the association of various effects (grain and grain boundary) by fitting electrical circuits at various temperature regions. This study tells the nature and conduction mechanism of the prepared sample. The Jonscher's universal power law is being followed by the frequency-dependent ac conductivity. [ABSTRACT FROM AUTHOR]

In this report, Ba1Bi1Cu1Fe1Ni1Ti3O12 (BBCFNTO termed further) ceramics were synthesized using a conventional ceramic processing route. The formation of multiple phases has been confirmed from by the XRD pattern at room temperature. The surface micrograph indicates the uniform distribution of grains with distinct grain boundary. The co-relation between the impedance and dielectric parameters was realized by using a phase sensitive meter over a good temperature and frequency range. The temperature- and frequency-dependent dielectric properties are linked to the conduction mechanism. The dielectric constant (K) and loss (tanδ) are increased sharply at high-temperature region, which is expected to be the onset of dipolar relaxation phenomena. The contribution of grain boundary (GBs) and grain (Gs) effects can be identified using the complex impedance spectroscopy. This synthesized material is investigated to model multifunctional devices. [ABSTRACT FROM AUTHOR]

In the present paper, fabrication and characterization (structural, electrical and ferroelectric properties) of a lead-free lanthanum (La) modified bismuth ferrite electroceramic having composition Bi(Fe0.5La0.5)O3 (BFLO) using various experimental techniques have been reported. BFLO has been synthesized by means of a high-temperature inter-diffusion of oxides method. This investigation mainly aims to correlate the phase formation and physical properties while the Fe-site of bismuth ferrite has partially been replaced by La. The surface micrograph shows the formation of the high dense ceramic sample. Analysis of data of various complex spectroscopies related to modulus and impedance exhibits the relaxation mechanism in this sample is of non-Debye type. The combined effect of grains and grain boundaries has been depicted from the Nyquist plot through the least-squares fitting of suitable circuit model along with the experimental data. The remnant polarization and coercive field decreases as temperature rises which was discerned from the ferroelectric loop obtained at different temperatures. The existence of ferroelectric nature in the sample was postulated from the polarization versus electric field plot. [ABSTRACT FROM AUTHOR]

In the present communication, studies of some physical properties (i.e., crystal data, permittivity, impedance, electrical cobnduction and magnetic) of a multiferroic material with a chemical composition (SmLi)1/2(Fe2/3Mo1/3)O3 have been reported. Thermogravimetric analysis of the compound, prepared by cost effective ceramic technology processing, was executed to check the mass loss as well as the required decomposition temperature of the ingredients. An analysis of X-ray spectra or pattern suggests that the crystallization phase or cystal system of the compound at room temperature is orthorhombic. The broad studies of dielectric properties {relative dielectric constant (εr), and tangent loss (tan δ)} display their independence of temperature and frequency in the rage of (30-375 °C) and (1 kHz-1 MHz) respectively. The impedance spectroscopic technique has provided a considerable significant information regarding the grain, grain boundary contribution within the sample and relaxation mechanism of the compound. The occurrence of negative temperature coefficient behaviour (NTCR) is depicted by the further analysis of impedance parameters. The frequency-temperature dependence of conductivity follows the Johnson’s power Universal law. The Arrhenius plot (i.e., variation of electrical conductivity with temperature) is used to calculate the activation energy. Analysis of magnetization (M-H) loop shows weak ferromagnetism of the compound. The material possesses significantly high magnitude of magnetoelectric coefficient of 3.0 mV Cm− 1 Oe− 1. [ABSTRACT FROM AUTHOR]

The polycrystalline sample of CaSnO3 modified BiFeO3-BaTiO3 with a composition 0.85BaTiO3-0.1BiFeO3-0.05CaSnO3 (hereafter BTO-BFO-CSO-5) was fabricated by a cost effective ceramic technology. The crystal system and unit cell dimensions of the prepared system were obtained by analyzing the room temperature X-ray spectra or pattern, and found to be an orthorhombic phase. The scanning electron micrograph shows the formation of the high-density ceramic sample. Resistive (impedance, modulus and electrical transport) and insulating (dielectric) properties of the system have been obtained using dielectric and the impedance spectroscopy at various frequencies (102-106 Hz) and temperatures (25-450 °C). The Nyquist plots exhibit the presence of the effect of grains in the prepared sample. The electrical transport properties of the material can be explained with the help of charge transfer by hopping process. The complex electrical modulus plot is used to determine the dielectric relaxation. The frequency dependence of conductivity plot follows the universal Jonscher power law. [ABSTRACT FROM AUTHOR]

The lead-free polycrystalline ceramic, barium titanate modified bismuth-sodium titanate 0.98 (BiNaTiO) + 0.02 BaTiO (BNT-BT-2) was synthesized by using a mixed oxide route at high temperature. The structural (crystal structure, microstructure, molecular structure), and electrical (dielectric constant and loss, impedance, conductivity) characteristics of the parent compound (BiNaTiO) have greatly been influenced by the addition of even a small amount of barium titanate in it. Preliminary structural study of BNT-BT-2 using X-ray diffraction data clearly shows the formation of a single-phase perovskite structure with the coexistence of hexagonal (major phase) and tetragonal (minor) phases. The existence of diffuse phase transtition and the relaxor behaviour in the material is confirmed by analysis of temperature-frequency dependence of dielectric parameters. The composition (0.98BNT − 0.02BT) of the material shows non-Ohmic conduction in its J-E characteristics. In this lead-free ceramic, permittivity anomalies are matched to modulus anomalies. The highlighted features are determined by structural phase transitions of the ferroelectric-like. [ABSTRACT FROM AUTHOR]

In the present paper, the effect of gallium (Ga) substitution on structural, microstructural, electrical conductivity of Pb(ZrTi)O (PZT) in the morphotropic phase boundary (MPB) region (i.e., PbGa(ZrTi)O (PGaZT-4)) was investigated. Increased grain density increases the resistivity of the Ga-modified PZT system. Preliminary structural analysis using X-ray diffraction pattern and data showed the existence of two phases [major tetragonal (T) and minor monoclinic (M)]. Field emission scanning electron micrograph (FESEM) showed the distribution of spherical as well as platelet type grains with small pores. The behavior of dielectric constant with temperature of PGaZT-4 exhibited the suppression of the ferroelectric phase transition [i.e., disappearance of Curie temperature ( T )]. The complex impedance spectroscopy (CIS) technique helped to investigate the impedance parameters of PGaZT-4 in MPB region in a wide range of temperature (250-500 °C) and frequency (1-1000 kHz) region. The impedance parameters of the material are found to be strongly dependent on frequency of AC electric field and temperature. The substitution of gallium at the Pb site of PZT generally enhances the dielectric constant and decreases loss tangent. The AC conductivity vs frequency ( f = ω2 π) in the region of dispersion follows the universal response of Jonscher's equation. Enhanced resistive characteristics were observed for Ga-substituted PZT in comparison to the pure PZT, which was well ensured from the studies of electrical parameters, such as impedance and AC conductivity. [ABSTRACT FROM AUTHOR]

Gallium (Ga) modified lead zirconate titanate (PbZrTiO) ceramics with Zr/Ti = 52/48 (i.e., near the morphotropic phase boundary) [i.e., Pb Ga (ZrTi)O = PGaZT-6] was fabricated by a mixed-oxide route at high temperatures. Based on determination of basic crystal data using X-ray pattern, single-phase orthorhombic phase of the prepared material obtained. Analysis of the field emission electron scanning microscopy images of the pellet (compacted) sample shows the homogeneous and densely packed grain distribution of varying shapes and size. The dielectric parameters of PGaZT-6 indicate the diffuse phase transition with non-relaxer characteristics of the material. The variation of these dielectric parameters with temperature and frequency of PGaZT-6 follows Jonscher's universal power law. Thermal (50-500 °C) and electric field (1-1000 kHz) effect on electrical impedance parameters of PGaZT-6 (near MPB) have been analyzed using impedance spectroscopy (IS) technique. Structure-properties of the material has been correlated using this complex technique. [ABSTRACT FROM AUTHOR]

Carbon quantum dots (CQDs) have recently emerged as innovative theranostic nanomaterials, enabling fast and effective diagnosis and treatment. In this study, a facile hydrothermal approach for N-doped biomass-derived CQDs preparation from Citrus clementina peel and amino acids glycine (Gly) and arginine (Arg) has been presented. The gradual increase in the N-dopant (amino acids) nitrogen content increased the quantum yield of synthesized CQDs. The prepared CQDs exhibited good biocompatibility, stability in aqueous, and high ionic strength media, similar optical properties, while differences were observed regarding the structural and chemical diversity, and biological and antioxidant activity. The antiproliferative effect of CQD@Gly against pancreatic cancer cell lines (CFPAC-1) was observed. At the same time, CQD@Arg has demonstrated the highest quantum yield and antioxidant activity by DPPH scavenging radical method of 81.39 ± 0.39% and has been further used for the ion sensing and cellular imaging of cancer cells. The obtained results have demonstrated selective response toward Fe3+ detection, with linear response ranging from 7.0 µmol dm−3 to 50.0 µmol dm−3 with R2 = 0.9931 and limit of detection (LOD) of 4.57 ± 0.27 µmol dm−3. This research could be a good example of sustainable biomass waste utilization with potential for biomedical analysis and ion sensing applications. [ABSTRACT FROM AUTHOR]

Cyclodextrin Metal-Organic Frameworks: A Green Metal-Organic Framework-Cyclodextrin MOF: A Novel Multifunctional Material Based Triboelectric Nanogenerator for Highly Efficient Mechanical Energy Harvesting (Adv. Funct. Keywords: cyclodextrin; metal-organic framework; self-powered applications; triboelectrics EN cyclodextrin metal-organic framework self-powered applications triboelectrics 1 1 1 07/10/21 20210709 NES 210709 In article number 2101829, Sitansu Sekhar Nanda, Hoe Joon Kim, and co-workers demonstrate the application of cyclodextrin metal-organic framework (CD-MOF), a green multifunctional material, to the electrifying layer of a multi-unit triboelectric nanogenerator. Cyclodextrin, metal-organic framework, self-powered applications, triboelectrics. [Extracted from the article]

Self-powered sensor development is moving towards miniaturization and requires a suitable power source for its operation. The piezoelectric nanogenerator (PENG) is a potential candidate to act as a partial solution to suppress the burgeoning energy demand. The present work is focused on the development of the PENG based on flexible polymer-ceramic composite films. The X-ray spectra suggest that the BTO particles have tetragonal symmetry and the PVDF-BTO composite films (CF) have a mixed phase. The dielectric constant increases with the introduction of the particles in the PVDF polymer and the loss of the CF is much less for all compositions. The BTO particles have a wide structural diversity and are lead-free, which can be further employed to make a CF. An attempt was made to design a robust, scalable, and cost-effective piezoelectric nanogenerator based on the PVDF-BTO CFs. The solvent casting route was a facile approach, with respect to spin coating, electrospinning, or sonication routes. The introduction of the BTO particles into PVDF enhanced the dielectric constant and polarization of the composite film. Furthermore, the single-layered device output could be increased by strategies such as internal polarization amplification, which was confirmed with the help of the polarization-electric field loop of the PVDF-BTO composite film. The piezoelectric nanogenerator with 10 wt% BTO-PVDF CF gives a high electrical output of voltage 7.2 V, current 38 nA, and power density of 0.8 μW/cm2 at 100 MΩ. Finally, the energy harvesting using the fabricated PENG is done by various actives like coin dropping, under air blowing, and finger tapping. Finally, low-power electronics such as calculator is successfully powered by charging a 10 μF capacitor using the PENG device. [ABSTRACT FROM AUTHOR]

Double perovskites have been extensively studied in materials chemistry due to their excellent properties and novel features attributed to the coexistence of ferro/ferri/antiferro-magnetic ground state and semiconductor band gap within the same material. Double perovskites with Sr2NiMO6 (M = Te, W) structure type have been synthesized using simple, non-toxic and costless aqueous citrate sol-gel route. The reaction yielded phase-pure nanocrystalline powders of two compounds: Sr2NiWO6 (SNWO) and Sr2NiTeO6 (SNTO). According to the Rietveld refinement of powder X-ray diffraction data at room temperature, Sr2NiWO6 is tetragonal (I4/m) and Sr2NiTeO6 is monoclinic (C12/m1), with average crystallite sizes of 49 and 77 nm, respectively. Structural studies have been additionally performed by Raman spectroscopy revealing optical phonons typical for vibrations of Te6+/W6+O6 octahedra. Both SNTO and SNWO possess high values of dielectric constants (341 and 308, respectively) with low dielectric loss (0.06 for SNWO) at a frequency of 1 kHz. These values decrease exponentially with the increase of frequency to 1000 kHz, with the dielectric constant being around 260 for both compounds and dielectric loss being 0.01 for SNWO and 0.04 for SNTO. The Nyquist plot for both samples confirms the non-Debye type of relaxation behavior and the dominance of shorter-range movement of charge carriers. Magnetic studies of both compounds revealed antiferromagnetic behavior, with Néel temperature (TN) being 57 K for SNWO and 35 K for SNTO. [ABSTRACT FROM AUTHOR]

Dense and stoichiometric Ba 0.8 Mg 0.2 (Zr 0.1 Ti 0.8 Ce 0.1) O 3 (BMZTCO) ceramics have been synthesised and their excitation was experimentally evaluated by applying an electric field. The processed sample exhibits superior frequency-independent and temperature-dependent dielectric parameters. The prepared sample has combined the tetragonal and cubic phases of BaTiO 3 and Ce 2 O 3 . The Bode plots suggest non-Debye type of relaxation mechanism and positive temperature coefficient-type behaviour. The excitation intensity reaches a peak when the driving frequency matches with the natural frequency of the prepared sample. [ABSTRACT FROM AUTHOR]

In the present work, the fused silica was fabricated using colloidal processing route. The fabricated samples were quenched (five time thermal cycling) and the results of the structural and electrical properties of the sintered sample and quenched sample have been studied and compared. The structural analysis confirmed the formation of the fabricated ceramics. The morphology of the sample suggested that there is close packing of the grains. The relaxation and conduction mechanism were analyzed using impedance and modulus spectroscopy. The dielectric parameters were inspected on varying temperature and frequency range. The impedance study showed the dependence of electrical properties on both frequencies and temperatures having corresponded with the morphology. [ABSTRACT FROM AUTHOR]

The bulk ceramics bearing chemical formula BiFeO3 and (BiLi)1/2(Fe2/3Mo1/3)O3 (abbreviated as BFO and BLFMO respectively) are synthesized using mixed oxide route. The physical properties (structural, dielectric, electric and magnetic) are tailored in Li and Mo co-doped BiFeO3. The phase evolution suggests that there is transformation from rhombohedral (pure BFO) to orthorhombic (BLFMO). Micro-structural suggests that due to co-doping the size of the grain is smaller than BFO. The dielectric properties of both BFO and BLFMO measure with an LCR meter varying the frequency (102–106 Hz) and temperature (30–375 °C). The leakage current decreases in BLFMO. The magnetic hysteresis loop owing weak ferromagnetism is depicted for Li and Mo co-doped BFO. The fabricated material will be base for various applications like filter and buffering. [ABSTRACT FROM AUTHOR]

A new polycrystalline ceramic sample of (Sb1/2Na1/2)(Fe2/3Mo1/3)O3 is formed by cheap mixed oxide processing technique. The mass loss and the calcination temperature of the sample are optimized by thermogravimetric analysis and repeated firing. The formed sample crystallizes in the orthorhombic crystal structure at room temperature depicted from the X-ray diffraction spectra. The dielectric relaxation, impedance and modulus analysis of the sample have been analyzed in various temperature and frequency range. The dielectric parameters of the sample depend on frequency and temperature and with an increment in temperature the relaxation time falls. Impedance spectroscopy analysis predicts the association of grain and grain boundary resistance. The short and long-range mobility of the charge carriers are illustrated by the modulus plot. Ac conductivity is seen to be temperature and frequency dependent and hopping of the charge carriers is also observed at high temperature. Further, the universal power law is followed by ac conductivity mechanism. [ABSTRACT FROM AUTHOR]

The polycrystalline samples having composition Bi0.45Eu0.02Na0.45Pb0.1Zr0.048Ti0.952O3 (BNPZTE-2 abbreviated ahead), Bi0.41Eu0.04Na0.45Pb0.1Zr0.048Ti0.952O3 (BNPZTE-4 abbreviated ahead), Bi0.39Eu0.06Na0.45Pb0.1Zr0.048Ti0.952O3 (BNPZTE-6 abbreviated ahead) had been synthesised using the mixed oxide processing route. The prepared samples were found to be in single phase and crystallize in tetragonal structure. The surface morphology suggests the high density grain growth in all samples. The electrical behavior (dielectric, impedance, and modulus) of the prepared samples collected at various temperatures and frequencies. The value of activation energy had been evaluated from the temperature dependent conductivity plot. The grain and grain boundary contribution to the polarization process have been depicted from the impedance analysis. The parallel plate capacitor structure was proposed to unveil the influence of applied electric field on the excitation of samples. The prepared samples will find its application in the filter application (noise removal) or buffering circuit. [ABSTRACT FROM AUTHOR]

The 70% BiFeO3 (BFO) with 30% PbTiO3 composite has attracted attention of many researchers, as it falls under MPB (morphotropic phase boundary) region. The studied composites 0.7(BiSmxFe1−xO3)-0.3(PbTiO3) for x = 0.0, 0.05, 0.10, 0.15, 0.20 were synthesized through the conventional route of solid-state reaction. The crystallization, symmetry (rhombohedral), and structural confirmation of the composites have been made through X-ray diffraction technique. The surface morphology of the natural surface is observed employing scanning electron microscope. The dielectric, impedance, and conductivity study reveals the electrical behavior of the samples. The dielectric permittivity is seen to rise with the increase in doping concentration. The high value of dielectric constant (7390.5) found for 10 wt% doping concentration of samarium. The composites are found to show negative temperature coefficient of resistivity behavior in the temperature range (275-350 °C). The relaxation phenomenon is reflected through impedance plots. From these results, it may be concluded that this material may be used for different high-temperature applications. [ABSTRACT FROM AUTHOR]

The barium doped bismuth sodium titanate (i.e., Bi0.49Na0.490.98Ba0.02)TiO3 (BNBT) powder was prepared by a conventional ceramic processing route. The thin film composites of BNBT- PVDF (polyvinylidene fluoride) were fabricated via a solution casting route. The scanning electron micrographs of the thin film samples show the homogenous distribution of grains with absence of cracks/pores. It is observed that with the increase of BNBT content in PVDF leads to enhancement in the dielectric permittivity and the reduction in the dissipation factor (tangent loss). The various electrical properties of the thin film samples were studied in the frequency range of 1 kHz to 1 MHz at different temperature between 25 and 100 °C. The prepared composite films have been used to study the (a) relationship between properties and crystal structure and (b) relaxation and conduction mechanism through the complex modulus and impedance spectroscopy. The contribution of grains was analyzed in the composite films by the fitting of equivalent circuit with the experimental data. An existence of the non-Debye type of dielectric relaxation was indicated by studying of the impedance and modulus parameters. The calculated activation energy from the temperature dependence of AC conductivity depicts hopping nature of charge carriers, which further explain the conduction process and mechanism in the prepared composites. [ABSTRACT FROM AUTHOR]