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Transparent and high efficient power sources harvesting energy from ambient environment is a desirable solution to on-site energy demand for organic electronic and optoelectronic devices. Here we report an integrated multi-unit transparent triboelectric nanogenerator (MT-TENG) for harvesting clean energy from ambient water motions. The instantaneous output power density reaches 27.86 mW/m 2 , which is 11.6 times of that generated from individual T-TENG with the same working dimension. The output of the MT-TENG can be further enhanced by miniaturizing the size of each single unit. In addition, the rational design of the MT-TENG increases the safety for future practical applications. The influence of temperature and pH value of water on the electric outputs is also systematically studied in consideration of different application environment. Given the compelling features, such as, high efficiency, cost-effective, easily implemented, it has great potential of integrating with building, vehicle or silicon-based solar cell to harvest clean energy from raindrop for powering electronics and constructing smart systems. [ABSTRACT FROM AUTHOR]

ZnFe 2 O 4 modified CdS quantum dots/ZnO nanorods core/shell structured photoanode has been designed and successfully fabricated. With the decoration of ZnFe 2 O 4 , both the photoelectrochemical performance and the stability of the CdS/ZnO photoanode were enhanced. The improved photoelectrochemical performance can be attributed to the typical stair-like type-II band alignment between ZnFe 2 O 4 , CdS and ZnO. The heterojunction between ZnFe 2 O 4 , CdS and ZnO can enhance the separation efficiency of the charge carriers. In addition, ZnFe 2 O 4 nanoparticles can serve as holes receptor of CdS and act as a protective layer which will reduce the photocorrosion of CdS and improve the stability of the photoanode. The optimized photoanode exhibited a remarkable solar-to-hydrogen efficiency of 4.4% which was 15.7 times than that of the pristine ZnO photoanode. This work provides a strategy for designing and fabricating stable and efficient photoanode. [ABSTRACT FROM AUTHOR]

Water is one of the most abundant energy sources in our environment and hydroelectric power has been one of the main forms of macro-energy supply. However, for harvesting green micro-energy from water presented in our residential zone, industry or agricultural irrigation, traditional electromagnetic hydraulic turbine generator has limited applications due to its large size, complexity and high cost. Here we report a novel design of the multi-unit hydroelectric generator (HEG) for harvesting water-related energy based on contact electrification. The instantaneous output power density of the multi-unit HEG array is 0.07 W/m 2 , which is 9 times of that from the individual HEG with the same dimension. Moreover, the rational design of the multi-unit HEG can increase the safety for its future service. By integrating with the multi-unit HEG, the household faucet can be a power source to supply clean energy continuously. Given the compelling features, such as, highly efficient, easily implemented, lightweight and extremely cost-effective, the multi-unit HEG renders a promising approach toward clean energy harvesting from ambient environment. [ABSTRACT FROM AUTHOR]

Developing photoanodes with high light-harvesting efficiency and great electronic transmission capacity remains a key challenge in photoelectrochemical (PEC) water splitting. In this paper, we reported an effective approach to enhance the PEC performance of ZnO nanowire arrays (NAs) photoanodes via overcoating ZnIn 2 S 4 nanosheets onto the ZnO surfaces. The ZnIn 2 S 4 electrocatalyst nanosheets were grown on the reduced graphene oxide (RGO) substrates by solvothermal synthesis and then grafted onto ZnO NAs, forming ZnO NAs/RGO/ZnIn 2 S 4 heterojunctions. The ZnIn 2 S 4 shells acted as visible light sensitizers, and the type-II band alignment between the ZnIn 2 S 4 shells and the ZnO cores contributed to charge separation and transport. Meanwhile, the introduction of RGO nanosheets largely increased the surface area and accelerated the PEC process by reducing the energy barrier of interfacial electrochemical reaction. As a result, over 200% enhancement of photo-to-hydrogen conversion efficiency was achieved from the ZnO NAs/RGO/ZnIn 2 S 4 heterojunctions compared to bare ZnO NAs. The results demonstrate that the RGO-based core/shell heterojunction arrays can provide a facile and compatible configuration for the potential applications in solar water splitting. [ABSTRACT FROM AUTHOR]

We demonstrated a sort of self-powered vibration sensor based on a triboelectric generator (TEG) using triboelectrification and electrostatic induction effects. The as-prepared TEG delivered an output voltage of 34.06 V and short-circuit current density of 22.5 mA/m 2 corresponding to a maximum power density of 0.77 W/m 2 , which was capable of driving five LEDs directly and continuously with working frequency of 50 Hz without any rectification circuit or energy storage unit. The vibration sensor has a detection range of 0–500 Hz, and high accuracy. Besides, it could realize detection under non-contact mode, which would protect the device and the detected object in operation. Moreover, the stability and repeatability could also be well retained. The TEG based vibration sensor possessed great potential in machines operation monitoring, process control, and security applications in unreachable and access-denied extreme environments. [ABSTRACT FROM AUTHOR]

One dimensional (1-D) nanostructures are envisioned as fundamental building blocks of future electronic, electromechanical, optoelectronic nanodevices and sensors, which will be integrated into nanosystems. We briefly introduce the advantages of 1-D nanostructure in the fabrication of energy conversion devices, followed by the recent developments in device designs, fabrication and some effective approaches for performance enhancement. This review will cover the major progress in three research fields. Firstly, we present the progresses on the fabrication and property modulation of wurtzite nanostructures. Then, we introduce the progresses on the piezotronic properties of wurtzite nano-materials and prototype piezotronic devices, including piezoelectric field effect transistors, piezoelectric diodes, strain sensors and nanogenerators. Finally, the investigations of property degrading and damage of nanomaterials, and functional degrading and failure of the nanodevices will be presented for future electronic applications. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we aim to discover the mechanics-related novel phenomena on high-quality ZnO microwires through nanoindentation method. The mechanical property parameters of ZnO microwires were determined and a distinctive creep damage phenomenon was revealed. By using the cycles load mode in the nanoindentation experiments, the indentation size effect was demonstrated to exist in the ZnO microwires: the elastic modulus ranged from 65.9GPa to 12.3GPa and the hardness changed from 11.1GPa to 1.8GPa with the increase of indentation depth. Furthermore, the indentation-induced mechanical and electrical damage caused a permanent plastic deformation and an increase of 41% in the longitudinal conductance of the ZnO microwires. [Copyright &y& Elsevier]

Abstract: Schottky-barrier ultraviolet (UV) detectors based on ZnO-nanowires (NWs) were fabricated with Pt as electrodes in this investigation. The ZnO NWs synthesized by the hydrothermal method were characterized by field-emission scanning electron microscopy (FE-SEM), Raman and PL spectroscopy. Photoelectric properties under 254 and 365 nm UV light were investigated. It is found that the photo-response properties of the devices under 365 nm UV light are better than those under 254 nm UV light, which is further illustrated by light transmission theory, energy-band diagram and absorption spectra. The results demonstrate that ZnO NWs detectors with selectivity to near-UV (NUV) light are promising candidates in photoelectric devices. [Copyright &y& Elsevier]

Abstract: In-doped ZnO nanostructures with four different morphologies, which are nanotetrapods, nanocombs, nanowires, and nanodisks, have been synthesized on silicon substrates by a simple thermal evaporation method. The XRD patterns show the In-doped ZnO nanostructures are all with the hexagonal wurtzite structure, and a slight difference in lattice parameters had been detected among the samples with various morphologies. The Raman spectra demonstrate that the vibrational mode of 2LA, which is very weak in undoped ZnO, was strongly enhanced with indium ion doping into ZnO structures. The photoluminescence (PL) measurements indicate that the nanodisks have a relative strong ultraviolet (UV) emission than other three kinds of samples. [Copyright &y& Elsevier]

It is highly important to develop high-performance sulfur cathode to solve low areal sulfur loading, shuttling and sluggish conversion of polysulfides for lithium-sulfur batteries. Herein, a three-dimensional (3D) freestanding framework configured with Co nanoparticles and Co-N x codoped carbon nanotubes anchored in a carbon foam is synthesized and investigated as a new type of sulfur host. Such an architecture can serve not only as a conductive carbon networks but also as host scaffold for high sulfur-containing electrodes. The hierarchical porous structures cooperated with high density and dispersion multifunctional Co-N x species can efficiently trap and manipulate catalytic conversion kinetics of polysulfides. Benefiting from above characteristics, the designed cathodes exhibit a high capacity (1259 mA h g−1) at 0.1 C and excellent cycling performance with an ultralow decay of 0.038% per cycle over 500 cycles at a high current density of 3 C. Even with a high sulfur loading (7.0 mg cm−2) and lean electrolyte (E/S = 5 μL mg−1) operation, a high areal capacity of 4.34 mA h cm−2 is still achieved after 100 cycles at 0.1 C. This work provides a low-cost route for preparation of freestanding cathode materials toward highly efficient lithium-sulfur batteries. [Display omitted] • The 3D freestanding material is flexible, compressible and can be directly used as a cathode for Li-S batteries. • Co-N x species can chemically anchor and catalytically manipulate conversion kinetics of polysulfides. • The cathode exhibits a high capacity of 1259 mA h g−1 at 0.1 C, excellent long-cycle performance with an ultralow decay of 0.038% at 3 C. • A high areal capacity of 4.34 mA h cm−2 is achieved for a high sulfur loading of 7.0 mg cm−2, and lean electrolyte (E/S = 5 μL mg−1). [ABSTRACT FROM AUTHOR]

Water electrolysis has been acknowledged as a renewable, scalable, and effective way of producing hydrogen. However, for water splitting, efficient and noble metal-free electrocatalysts were lacking. Here, a Co–Ni–Zn porous three-dimension N-doped carbonization structure on the carbon nanotube film (CNTF) was synthesized through a metal organic frameworks (MOFs) annealing procedure. The porous morphology, caused by the evaporation of zinc at high temperatures, enhances the interaction between the catalysts and electrolyte, and the self-supporting structure minimizes the contact resistance between the catalysts and the substrate, which reduces obstructions during current flow. More active sites, multiple mesopores, and high conductivity are all features of this composite structure. It can achieve a small overpotential of 112 mV and 270 mV at a current density of 10 mA cm−2, respectively, for hydrogen and oxygen evolution reactions (HER and OER). At a current density of 10 mA cm−2, the Co–Ni–Zn/NCNTF has an external voltage of 1.58 V and is very durable for overall water splitting. [Display omitted] • Ni- and Zn-doped MOFs grow in-situ on a CNT film. • Zn doping increases contact area between catalysts and electrolyte. • A self-supporting structure minimizes the contact resistance. • This catalyst is an efficient bifunctional catalyst. [ABSTRACT FROM AUTHOR]

Abstract: Qualitative and quantitative detection of biological and chemical species is crucial in many areas, ranging from clinical diagnosis to homeland security. Due to the advantages of ultralow detection limit, label-free, fast readout and easy fabrication over the traditional detection systems, semiconductor nanowire based electronic devices have emerged as a potential platform. In this paper, we fabricated a single ZnO nanowire-based biologically sensitive field-effect transistors (bioFETs) for detection of different concentrations of uric acid solution at the same time. The addition of uric acid with the concentrations from 1pM to 0.5mM resulted in the electrical conductance changes of up to 227nS, and the response time turns out to be in the order of millisecond. The ZnO NW biosensor could easily detect as low as 1pM of the uric acid with 14.7nS of conductance increase, which implied that the detection limit of the biosensor can be as low as 1pM. [Copyright &y& Elsevier]

Abstract: TiO2–graphene nanosheets (GNS) composites are prepared via an in situ chemical synthesis method, which enables a homogenous dispersion of TiO2 nanoparticles on the graphene nanosheets. The obtained TiO2–GNS composites are anatase-GNS, while TiO2 is nanosized rutile without the incorporation of GNS. The resulting TiO2–GNS composites are employed as anode materials for lithium-ion batteries, showing a high initial reversible capacity of 306mAhg−1 as well as a good cycling stability. The TiO2–GNS composites can deliver 60mAhg−1 at a current rate as high as 5Ag−1 and demonstrate negligible fade even after 400 cycles. The superior electrochemical performances of the TiO2–GNS composites can be attributed to their unique structures, which intimately combine the conductive graphene nanosheets network with uniformly dispersed TiO2 nanoparticles. The TiO2–GNS composites could be promising candidate materials for high-power, low-cost, and environmentally friendly anodes for lithium ion batteries. [Copyright &y& Elsevier]

Abstract: The one-dimensional (1D) Zn1−x Ni x O (x =0, 0.02, 0.05, 0.10) nanorods have been synthesized by a simple hydrothermal method. New bands show at ∼130cm−1 in the Raman spectra of Ni-doped ZnO nanorods and their relative intensity depends on the doping concentration of nickel. The optical band gap of the ZnO nanorods have been tuned by Ni-doping, which is revealed by absorption spectra. The photocatalytic activity of Zn1−x Ni x O was studied by comparing the degradation rate of rhodamine B (RB) under UV-light irradiation. It was found that Zn0.95Ni0.05O exhibited the highest photocatalytic degradation efficiency among the samples. [Copyright &y& Elsevier]

• The influence of radial structure on magnification performance was studied. • The effect of coating layer on the stability of composite electrode was studied. • B-NCM@LNO5 cathode exhibited a high rate and long cycle durability. Nickel-rich cathode materials play a pivotal role in the functioning of lithium-ion batteries, but their crystal structure defects and surface side reactions significantly affect battery performance. This has slowed down the commercialization process of nickel-rich cathodes. To remedy these problems, a new strategy utilizing B and Nb for crystal structure and interface control of LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) is proposed in this study. The B Nb modified cathode exhibits strong radial orientation and exposes a large number of active (003) lattice plane on the particle surface. This structural control reduces micro-cracks and accelerates lithium-ion diffusion kinetics. Additionally, the LiNbO 3 coating effectively avoids immediate contact between secondary particles and the electrolyte, greatly alleviating side reactions. Consequently, the optimal cathode B-NCM@LNO5 modified cathode maintains a capacity retention of 86.71% after 200 cycles at 1 C, outperforming the original material (76.11% retention). Meanwhile, it demonstrates attractive rate capability of 158.4 mAhg−1 under 5 C. This research provides valuable insights for addressing anisotropic strain and interface compatibility issues in nickel-rich cathodes. [ABSTRACT FROM AUTHOR]

The electrochemical splitting of water is considered to be an efficient and potential technique for producing clean hydrogen and oxygen. Although, there are lots of significant developments in composite of superior hydrogen evolution reaction (HER) or oxygen evolution reaction (OER) catalyst applied in water splitting currently, designing non-precious and low-cost bifunctional electrocatalysts with high performance is still an attractive challenging issue. In this article, we report a novel bifunctional electrocatalyst with cobalt-based nanoparticles (NPs) embedded in Zn-doped hierarchical porous three-dimension N-doped carbonization structure via an annealing process of metal organic frameworks (MOFs) connected by N-doped carbon nanotube (denoted as Co–Zn/PNC). This composite structure possesses the characteristics of more active sites, numerous mesopores and high conductivity. The resulting electrocatalyst (Co–Zn/PNC) can be used as both anode and cathode to roust the overall water splitting, getting a current density of 10 mA cm−2 at a cell voltage of 1.63 V in 1.0 M KOH electrolyte. • Co–Zn/PNC is prepared by Zn-doped ZIF-67 linked by N-doped CNT through pyrolysis. • Bifunctional electrocatalyst Co–Zn/PNC exhibits excellent HER and OER performance. • Zn doping can enhance the electrochemical performance of Co–Zn/PNC. [ABSTRACT FROM AUTHOR]

Potentially useful anodic material with prospects for use within rechargeable lithium-ion batteries are fabricated from silicon (Si)-based compounds. The active Si/electrolyte contact and weak conductivity, however, constantly produce side reactions, which dramatically reduce cycling stability. The only metallic current collector that demonstrates to facilitate lithium-ion transfer and electron conduction without alloying reactions is copper (Cu). In this study, we created Si-based multicomponent anode materials made of Si/Cu/Cu 3 Si alloy nanoparticles (Si/Cu/Cu 3 Si@C) coated in amorphous carbon. This is accomplished utilizing a straightforward, low-cost approach that combines hydrothermal technology and high-intensity ball milling. To further increase conductivity, Si/Cu/Cu 3 Si alloy is used as the active component. Through the use of a micro-sized amorphous carbon-coated structure, the volume problem of the active material can be successfully resolved. Additionally, the micro-sized amorphous carbon may inhibit nanoparticle agglomeration and alloy interfacial side reactions. As a result, it is anticipated that the Si/Cu/Cu 3 Si@C composite will display favorable electrochemical performances and possess a remarkable reversible specific capacity of 984 mAh g−1 at 0.5 C. The GITT test is used to determine the D Li + of the Si/Cu/Cu 3 Si@C electrode, which ranges from 10−11 to 10−8 cm−2 s−1. Additionally, the full-cell is constructed by coupling a Li(Ni 1/3 Co 1/3 Mn 1/3)O 2 (NCM111) cathode with a solution-based chemically Si/Cu/Cu 3 Si@C anode that exhibits an enhanced initial coulombic efficiency (84.9%) and outstanding cycle performance. • Si-based multicomponent anode materials made of Si/Cu/Cu 3 Si alloy nanoparticles (Si/Cu/Cu 3 Si@C) coated in amorphous carbon. • In-situ encapsulation of Si/Cu/Cu 3 Si alloy forming sucrose derived carbon have been developed to improve the performance and retain the structural integrity of the electrode. • Cu/Cu 3 Si alloy help to reduce internal electrical resistance and suppress the volume expansion of Si-based electrodes, which results in the extended life of Si-based LIBs. • The full-cell with the chemical prelithiated anode and Li(Ni 1/3 Co 1/3 Mn 1/3)O 2 cathode delivers a high 85% capacity retention after 200 cycles. [ABSTRACT FROM AUTHOR]

Primary open-angle glaucoma (POAG) is a leading cause of irreversible blindness. Magnetic resonance imaging (MRI) studies report an association between POAG and nonvisual pathway alterations. Locus coeruleus (LC) is a major source of norepinephrine released in the brain, and norepinephrine can reduce intraocular pressure via increasing aqueous outflow. This study aimed to investigate the relationship between glaucoma and the LC in patients with POAG and animal models. Resting-state functional MRI was performed using a 3-Tesla MR scanner with an eight-channel phased-array head coil, and MRI data were analyzed. A rat model of chronic glaucoma was generated by episcleral vein ligation and cauterization. DBA/2J mice that develop glaucoma with age were also acquired. Immunohistochemistry and immunofluorescence staining were used to investigate LC tyrosine hydroxylase (TH) and dopamine β-hydroxylase (DβH) expression, as well as cell apoptosis by terminal deoxynucleotidyl transferase dUTP Nick-End Labeling staining. Patients with POAG showed significantly increased amplitude of low-frequency fluctuation (ALFF) in the LC compared with controls. LC ALFF values showed significant correlations with cup-to-disk ratio, retinal nerve fiber layer thickness, and visual function ( P  < 0.05). Functional connectivity (FC) between the LC and frontal and insular lobes was reduced, but elevated between the LC and parahippocampal gyrus, compared with controls. Glaucoma animal models revealed reduced expression of TH and DβH in the LC, and increased cell apoptosis. In this study, we provide novel evidence for the relationship between the LC and glaucoma. The LC may act as a network in POAG pathogenesis and intraocular pressure regulation. [ABSTRACT FROM AUTHOR]

Abstract: Graphene nanosheets were prepared by reducing graphite oxide with hydrazine hydrate. The effects of reduction time on the structure and morphology of graphene nanosheets have been investigated. Their electrochemical performance in aqueous and organic electrolytes was also analyzed. With an increase of reduction time, the C and N contents of graphene nanosheets increased, while the specific surface areas and the specific capacitances decreased. Changes in reduction time produced a significant effect on the numbers as well as the types of oxygen and nitrogen functionalities. The graphene nanosheets, prepared by using a reduction time of 30min have the highest specific capacitance of 192Fg−1 in a 6molL−1 KOH electrolyte. All prepared graphene nanosheets have a good rate performance and cycle stability. [Copyright &y& Elsevier]

• An N-doped CNT-interspersed hierarchical carbon shell structure by Co-Zn bimetallic ZIFs-triggered surface polymerization of dopamine has been designed and successfully prepared for stabilized silicon anode (PDA@CoZn-NC@Si). • PDA@CoZn-NC@Si electrodes deliver better cycle stability of 814 mAh/g at 0.5C with a capacity loss of −0.14% per cycle over 400 cycles and possess excellent rate capability. • The solution-based chemical prelithiation method is used to compensate for irreversible loss of anode capacity, and the full cell exhibits an improved ICE (88.3%) and a higher energy density (419.8 Wh kg−1). The application of silicon-based anode remains a serious challenge due to its intrinsic volumetric expansion effect and low conductivity. In our work, a novel CNT-interspersed hierarchical carbon shell structure (denoted as PDA@CoZn-NC@Si) is synthesized by wrapping Si uniformly in the bimetallic zeolite imidazolate frameworks (ZIFs) and then encapsulated with a dopamine-derived carbon shell. The PDA@CoZn-NC@Si anode delivers better cycle stability of 814 mAh/g at 0.5C for 400 cycles (only −0.14% capacity reduction per cycle) and possesses excellent rate capability, which benefits from the inner porous buffer spaces, interspersed CNT, and solid heterogeneous carbon shells. In addition, the full cell is assembled by pairing a solution-based chemically prelithiated PDA@CoZn-NC@Si anode with a Li(Ni 1/3 Co 1/3 Mn 1/3)O 2 (NCM111) cathode, and it presents an improved initial coulombic efficiency (88.3%) and a high energy density (419.8 Wh/kg). This study provides effective guidance for optimizing the microstructure design and prelithium of Si-based anodes. [ABSTRACT FROM AUTHOR]

• A three-dimensional Ni,Co-embedded CNT-coated N-doped hollow porous carbon (Ni/Co-CNT/NHPC) cathode has been designed and prepared for lithium-sulfur battery. • The Ni/Co-CNT/NHPC-S cathode possesses a high specific capacity of 1352 mA h g-1 and an excellent cycle stability at 1 C with low capacity decay of 0.094% per cycle over 500 cycles. • The mechanism of suppressing the shuttle effect on the cathode materials is discussed by analyzing adsorption experiments and density functional theory（DFT）calculation. Lithium-sulfur (Li-S) batteries have attracted great attentions due to their high specific capacity. However, the poor cycle stability caused by polysulfide shuttles, volume expansion and formation of lithium dendrites limit their practical applications. In the present work, to tackle the poor stability and unstable rate capability, a MOF-doping strategy is developed to construct a hollow porous carbon framework，which consists of Ni, Co particles and CNT on a N-doped shell surface (Ni/Co-CNT/NHPC). This hollow framework increases the load of S, slows down the volume changes, and can physically entrap soluble polysulfide. It is found that the CNT-coated network structure is beneficial for optimizing the conductivity and wettability of the material, which accelerates the reaction kinetics. Moreover, synergistic effect of abundant defects and Ni, Co nanoparticles strengthens the chemisorption of polysulfides, which suppresses the shuttle effect. As a consequence, the Ni/Co-CNT/NHPC-S cathode harvests a high specific capacity (1352 mA h g-1), and shows an excellent cycling stability at 1 C with low capacity decay of 0.094% over 500 cycles. [ABSTRACT FROM AUTHOR]