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[Display omitted] • A novel proton exchange membrane was prepared by adding OA-POSS-g-GO into SPEEK. • Grafting on uniquely structured GO led to interconnected, well-dispersed OA-POSS. • The –NH 2 and -SO 3 H formed acid-base pair and enhanced interfacial interaction. • Interaction was optimized to control the ion channel and the state of water. • Enhanced compatibility and interaction at the interface improved PEM performance. Nano octa-aminopropyl polyhedral oligomeric silsesquioxane (OA-POSS) was grafted into graphene oxide (GO) via covalent bonding to synthesize OA-POSS-g-GO. A novel SP/OA-POSS-g-GO proton exchange membrane was prepared by adding sulfonated poly (ether ether ketone) (SPEEK, SP). OA-POSS was well dispersed on GO to form an ordered acid-base pair with SPEEK, which facilitated the construction of continuous ion channels. GO as a carrier facilitated the construction of long-range proton conduction pathways in the membrane. The strong interactions between OA-POSS and SPEEK along with the synergistic effect of GO modulate the size of ionic clusters and increased the bound water ratio within the membrane. The conductivity of the SP/OA-POSS-g-GO-2 membrane (80 °C, 95% RH) reached 0.2096 S⋅cm−1, which was 1.7 times higher than that of the SPEEK membrane (0.1265 S⋅cm−1). The conductivity of the SP/OA-POSS-g-GO-2 membrane increased at 100 °C and 40% RH, while that of the SPEEK membrane decreased with the temperature increased above 80 °C. The maximum power density of the single cell assembled from the composite membrane reached 305.8 mW⋅cm−2 at 80 °C and 95% RH, which was 1.4 and 1.3 times higher than that of the SPEEK and Nafion 117 membrane, respectively. [ABSTRACT FROM AUTHOR]

A self-charging power cell (SCPC) is a structure that hybridizes the mechanisms for energy conversion and storage into one process through which mechanical energy can be directly converted into electrochemical energy. A key structure of an SCPC is the use of a polyvinylidene fluoride (PVDF) piezo-separator. Herein, we have fabricated a piezoelectric β-form PVDF separator with a highly porous architecture by introducing ZnO particles. The electrochemical charge/discharge performance of this SCPC was greatly enhanced at lower discharge rates compared to highly stretched (high-β-content) or less porous PVDF membranes. The lower charge-transfer resistance of this well-developed porous piezo-separator is the main factor that facilitated the transport of Li + ions without sacrificing piezoelectric performance. This study reveals a novel approach for improving the performance of SCPCs. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerator technology is emerging as a promising candidate for mechanical energy harvesting from ambient environment. Freestanding triboelectric-layer-based nanogenerators (FTENGs) are one of the fundamental operation modes with many advantages. In this paper, the first theoretical model of FTENGs is proposed with thorough analysis of their operation principle. Both contact-mode and sliding-mode FTENGs are discussed to fully uncover their unique characteristics. Contact-mode FTENGs have superior linearity, which is highly beneficial for both energy-harvesting and self-powered sensing applications. Sliding-mode FTENGs have two subcategories based on the material of their freestanding layer. For both of the two subcategories, the coupling effect of the height of the freestanding layer and the electrode gap on their output characteristics are discussed in detail to obtain the strategy for their structural optimization. [ABSTRACT FROM AUTHOR]

The development of internet of things and the related sensor technology have been a key driving force for the rapid development of industry and information technology. The requirement of wireless, sustainable and independent operation is becoming increasingly important for sensor networks that currently could include thousands even to millions of sensor nodes with different functionalities. For these purposes, developing technologies of self-powered sensors that can utilize the ambient environmental energy to drive the operation themselves is highly desirable and mandatory. The realization of self-powered sensors generally has two approaches: the first approach is to develop environmental energy harvesting devices for driving the traditional sensors; the other is to develop a new category of sensors – self-powered active sensors – that can actively generate electrical signal itself as a response to a stimulation/triggering from the ambient environment. The recent invention and intensive development of triboelectric nanogenerators (TENGs) as a new technology for mechanical energy harvesting can be utilized as self-powered active mechanical sensors, because the parameters (magnitude, frequency, number of periods, etc.) of the generated electrical signal are directly determined by input mechanical behaviors. In this review paper, we first briefly introduce the fundamentals of TENGs, including the four basic working modes. Then, the most updated progress of developing TENGs as self-powered active sensors is reviewed. TENGs with different working modes and rationally designed structures have been developed as self-powered active sensors for a variety of mechanical motions, including pressure change, physical touching, vibrations, acoustic waves, linear displacement, rotation, tracking of moving objects, and acceleration detection. Through combining the open-circuit voltage and the short-circuit current, the detection of both static and dynamic processes has been enabled. The integration of individual sensor elements into arrays or matrixes helps to realize the mapping or parallel detection for multiple points. On the other hand, the relationship between the amplitude of TENG-generated electrical signal and the chemical state of its triboelectric surface enables TENGs to function as self-powered active chemical sensors. Through continuous research on the TENG-based self-powered active sensors in the coming years to further improve the sensitivity and realize the self-powered operation for the entire sensor node systems, they will soon have broad applications in touch screens, electronic skins, healthcare, environmental/infrastructure monitoring, national security, and more. [ABSTRACT FROM AUTHOR]

Demonstrating integrated triboelectric nanogenerator energy harvesting systems that contain triboelectric nanogenerators, power management circuits, signal processing circuits, energy storage elements, and/or load circuits are core steps for practical applications of triboelectric nanogenerators. Through the design flow of such systems, theoretical simulation plays a critical role. In this manuscript, we provided a new theoretical simulation method for integrated triboelectric nanogenerator systems through integrating the equivalent circuit model of triboelectric nanogenerators into SPICE software. This new simulation method was validated by comparing its results with analytical solutions in some specific triboelectric nanogenerator systems. Finally, we employed this new simulator to analyze the performance of an integrated triboelectric nanogenerator system with a power management circuit. From the study of the influence of different circuit parameters, we outline the design strategy for such kind of triboelectric nanogenerator systems. [ABSTRACT FROM AUTHOR]

Abstract: New technologies that can scavenge ambient environmental energy have attracted increasing interest in the past decades. Recently, triboelectric nanogenerator (TENG) has been demonstrated as a powerful approach for harvesting various forms of mechanical energies. In this work, a newly designed TENG is demonstrated by coaxially integrating multiple layers disk TENGs into a whole system, which transforms the fluid flow into rotation motion of multiple layers disks and generates a multiplied electrical output. To achieve the effective structural integration and output multiplication, a D-shape shaft is adopted to facilitate the synchronized relative rotation of all the segmentally-structured disk layers and light weight and low stiffness springs are employed to ensure the intimate contact of the tribo-surfaces. With the above design, the nanogenerator delivers an open-circuit voltage up to ~470V and a short-circuit current density of 90.6mA/m2, corresponding to an instantaneous maximum power density of 42.6W/m2 (2.68kW/m3) at a rotation speed of 1000rpm. By combining the TENG with a water turbine, the device can be effectively driven by a water flow from a common household faucet. This technology represents an important advance of TENGs toward practical applications and shows great potential in hydroelectric power and wind power industries. [Copyright &y& Elsevier]

Abstract: Harvest mechanical energy with variable frequency and amplitude in our environment for building self-powered systems is an effective and practically applicable technology to assure the independently and sustainable operation of mobile electronics and sensor networks without the use of a battery or at least with extended life time. In this study, we demonstrated a novel and simple arch-shaped flexible triboelectric nanogenerator (TENG) that can efficiently harvesting irregular mechanical energy. The mechanism of the TENG was intensively discussed and illustrated. The instantaneous output power of single TENG device can reach as high as∼4.125mW by a finger typing, which is high enough to instantaneously drive 50 commercial blue LEDs connected in series, demonstrating the potential application of the TENG for self-powered systems and mobile electronics. [Copyright &y& Elsevier]

A phytochemical study of Cortex Moutan (the dried root bark of Paeonia suffruticosa Andrews) led to the isolation of 24 compounds, including eleven mono-phenols (1 – 11), seven terpenoids (12 – 18), three flavonoids (19–21), two sterols (22 and 23) and one coumarin (24). The structures of these isolated compounds were identified using NMR spectroscopy (1H and 13C) by comparison with previously reported data. To the best of our knowledge, compounds 5 , 11 , 15 , 16 , 22 , and 24 were reported from this plant for the first time. The chemotaxonomic significance of the isolates was also discussed. [Display omitted] • Cortex Moutan is a herbal remedy broadly utilized in Traditional Chinese Medicine. • The hydroalcoholic extract from Cortex Moutan was investigated. • Twenty-four compounds were purified and identified mainly by means of NMR tools. • The chemotaxonomy significance was discussed. [ABSTRACT FROM AUTHOR]

Ochratoxin A (OTA), a mycotoxin produced by Aspergillus ochraceus and Penicillium verrucosum , is one of the most significant mycotoxins encountered in foods. In this research, a novel fluorescence biosensing strategy for simple and sensitive OTA detection using an aptamer specific for OTA as recognition element and single-walled carbon nanohorns (SWCNHs) as fluorescence quencher was reported. In the absence of target molecule (OTA), FAM (carboxyfluorescein)-modified aptamer was adsorbed onto the SWCNH surface. In this arrangement, the fluorophore and quencher were in close proximity; thus, FAM fluorescence was readily quenched by fluorescence resonance energy transfer from dye to carbon nanohorn. In the presence of target molecules (OTA), the OTA-specific aptamer form an antiparallel G-quadruplex, which is resistant to being wrapped onto SWCNHs. Therefore, the fluorescence of FAM cannot be quenched, and the fluorescent intensity as a function of OTA concentration was correspondingly measured. We obtained a detection limit of 17.2 nM for our sensing platform based on SWCNHs, with a linear detection range of 20–500 nM. The proposed assay system also exhibited high selectivity for OTA against other mycotoxins. The biosensor was verified for real sample application by testing 1% red wine containing buffer solution spiked with a series of OTA concentrations, and there is a good linear relationship (correlation coefficient = 0.990) between the fluorescence intensity and the logarithm of OTA concentration. Utilization of the proposed biosensor for quantitative determination of mycotoxins in food samples indicated the sensor being a useful tool for verifying the effectiveness of mycotoxin control strategies. [ABSTRACT FROM AUTHOR]

Besides targeting at the worldwide energy needs at a large scope, we have been developing an area of nanoenergy, aiming at using nanotechnology to harvest the energy required for sustainable, independent and maintenance free operation of micro/nano-systems and mobile/portable electronics. As first reported in 2006, various nanogenerators (NGs) have been demonstrated using piezoelectric, triboelectric and pyroelectric effects. By using the energy from our living environment, our goal is to make self-powered system. The self-powering approaches developed here are a new paradigm in nanotechnology and green energy for truly achieving sustainable self-sufficient micro/nano-systems, which are of critical importance for sensing, medical science, infrastructure/environmental monitoring, defense technology and personal electronics. [ABSTRACT FROM AUTHOR]