Publications by authors named "Haiwu Zheng"

The abundant water wave energy on Earth stands as one of the most promising renewable blue energy sources, as it exhibits minimal dependence on weather, time and temperature. However, the low fluctuation frequency and extremely irregular nature of the wave energy restrict both the methods and efficiency of energy harvesting. In this study, a packed box-like hybrid nanogenerator was designed, comprising two single-electrode triboelectric nanogenerators (TENGs) and two electromagnetic generators (EMGs).

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Amorphous GaO (a-GaO) films have attracted considerable attention in the field of photodetectors due to their excellent optical absorption response and photoelectric properties. However, there are few studies that have utilized the piezo-phototronic effect to regulate the broadband photoresponse of GaO-based photodetectors. Here, a flexible a-GaO/ZnO heterojunction was constructed, which demonstrated a broadband response range from deep ultraviolet (265 nm) to the near-infrared (1060 nm) and realized a bidirectional adjustable photocurrent response the piezo-phototronic effect.

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Polymer-based dielectric nanocomposites have attracted great attention due to the advantages of high-power density and stability. However, due to the limited breakdown strength () of the dielectrics, the unsatisfactory energy density becomes the bottleneck that restricts their applications. Here, newly designed sandwich-structured nanocomposites are proposed, which includes the introduction of low-loading 0.

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With the rapid development of the Internet of Things, the maintenance-free and reliable power supply of widely distributed sensors is still a huge challenge, especially in wireless areas. Wireless power transmission is expected to alleviate the issue that the sensors must be connected by wire to power supply devices. Herein, a novel hybrid nanogenerator combining a triboelectric nanogenerator (TENG) and photovoltaic cell has been demonstrated, which can realize the simultaneous collection and wireless power transmission of swinging mechanical energy and solar energy.

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A large coercive field (E) and ultrahigh piezoelectricity are essential for ferroelectrics used in high-drive electromechanical applications. The discovery of relaxor-PbTiO crystals is a recent breakthrough; they currently afford the highest piezoelectricity, but usually with a low E. Such performance deterioration occurs because high piezoelectricity is interlinked with an easy polarization rotation, subsequently favoring a dipole switch under small fields.

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Flexible piezoelectric nanogenerators (PENG) have attracted great attention due to their stable electrical output and promising applications in the Internet of Things. To develop a high-performance PENG, a significant relationship among material, structure, and performance precipitates us to design its rational construction. Herein, Tb-modified (BaCa)(ZrTi)O (BCZT) particles have been fabricated into a 3D structure (3D-Tb-BCZT) by the freeze-drying method, and the innovative 3D core/shell structure of 3D-Tb-BCZT-coated 3D-Tb-BCZT/PVDF composite fibers was carried out through the coaxial electrospinning method.

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Biomedical electronic devices have enormous benefits for healthcare and quality of life. Still, the long-term working of those devices remains a great challenge due to the short life and large volume of conventional batteries. Since the nanogenerators (NGs) invention, they have been widely used to convert various ambient mechanical energy sources into electrical energy.

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With the popularity of portable and miniaturized electronic devices in people's live, flexible piezoelectric nanogenerators (PENG) have become a research hotspot for harvesting energy from the living environment to power small-scale electronic equipment and systems because of its stability. For further enhancing output performance of PENG, chemical modification and structural design for piezoelectric fillers are effective ways. Thus, the 3D porous hetero-structure fillers of BCZT@Ag are prepared by freeze-drying method and subsequent chemical seeding reduction.

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Wearable triboelectric nanogenerators (TENGs) have recently attracted great interest because they can convert human biomechanical energy into sustainable electricity. However, there is a need for improvement regarding the output performance and the complex fabrication of TENG devices. Here, a triboelectric nanogenerator in single-electrode mode is fabricated by a simple strategy, which involves a sandwich structure of silicone rubber and silver-coated glass microspheres (S-TENG).

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Ferroelectric materials have drawn widespread attention due to their switchable spontaneous polarization and anomalous photovoltaic effect. The coupling between ferroelectricity and the piezo-phototronic effect may lead to the design of distinctive photoelectric devices with multifunctional features. Here, we report an enhancement of the photovoltaic performances in the ferroelectric -type La-doped bismuth ferrite film (BLFO)/-type zinc oxide (ZnO) nanowire array heterojunction by rationally coupling the strain-induced piezoelectricity in ZnO nanowires and the ferroelectricity in BLFO.

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Contact-electrification is a universal effect for all existing materials, but it still lacks a quantitative materials database to systematically understand its scientific mechanisms. Using an established measurement method, this study quantifies the triboelectric charge densities of nearly 30 inorganic nonmetallic materials. From the matrix of their triboelectric charge densities and band structures, it is found that the triboelectric output is strongly related to the work functions of the materials.

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Rational design of photocatalysts with heterostructure is of scientific and technological interest for taking full advantage use of solar energy. Here we demonstrate a facile method to fabricate ZnCdS/BiS composite nanospheres, in which BiS nanorods grown on the surface of ZnCdS nanospheres. The as-prepared ZnCdS@ZnS core-shell nanospheres play a vital role in formation of the ZnCdS@BiS composite nanospheres.

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Triboelectrification is a well-known phenomenon that commonly occurs in nature and in our lives at any time and any place. Although each and every material exhibits triboelectrification, its quantification has not been standardized. A triboelectric series has been qualitatively ranked with regards to triboelectric polarization.

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Triboelectric nanogenerators (TENGs) have been investigated for mechanical energy harvesting because of their high-energy conversion efficiency, low cost, ease of manufacturing, and so on. This paper deals with designing a kind of water-fluid-driven rotating TENG (WR-TENG) inspired by the structure of a water meter. The designed WR-TENG is effectively integrated into a self-powered electrostatic scale-preventing and rust protection system.

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Retraction of 'Comprehensive insights into the charge dynamics process and excellent photoelectric properties of heterojunction solar cells' by Xiangyang Liu et al., Phys. Chem.

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The development of p-type metal oxide thin-film transistors (TFTs) is far behind the n-type counterparts. Here, p-type CuAlO thin films were deposited by spin coating and annealed in nitrogen atmosphere at different temperature. The effect of post-annealing temperature on the microstructure, chemical compositions, morphology, and optical properties of the thin films was investigated systematically.

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Correction for 'Comprehensive insights into the charge dynamics process and excellent photoelectric properties of heterojunction solar cells' by Xiangyang Liu et al., Phys. Chem.

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With the rapid development of portable electronics, exploring sustainable power sources is becoming more and more urgent. Utilizing a nanogenerator to harvest ambient mechanical energy could be an effective approach to solve this challenge. In this work, a novel spring-assisted hybrid nanogenerator (HG) consisting of a triboelectric nanogenerator (TENG) and an electromagnetic generator (EMG) was developed for harvesting low-frequency vibration energy.

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A dye-sensitized and flexible TiO fiber with multilayer structure was prepared by using brush method as the photoanode in the efficient flexible fibrous dye-sensitized solar cells (FFDSSCs) to avoid electronic recombination and improve the electronic capture efficiency. The composite Pt counter electrode, preparation from the surface modification of the electrodeposited Pt wire by using a simple one-step thermal decomposition approach of HPtCl isopropanol and n-butyl alcohol (volume ratio = 1:1) solution, provided a significant improvement in electrocatalytic activity, which was confirmed by extensive electrochemical tests. The FFDSSC assembled with the fiber-shaped TiO photoanode and the composite Pt counter electrode achieves an enhanced photoelectric conversion efficiency of 6.

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Harvesting energy available from ambient environment is highly desirable for powering personal electronics and health applications. Due to natural process and human activities, steam can be produced by boilers, human perspiration, and the wind exists ubiquitously. In the outdoor environment, these two phenomena usually exist at the same place, which contain heat and mechanical energies simultaneously.

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Zn2SnO4 octahedron nanoparticles/Cu4Bi4S9 (ZTO/CBS) and ZTO octahedron nanoparticles/CBS-graphene nanoplatelets (ZTO/CBS-GNs), as well as two types of bulk heterojunction (BHJ) solar cells with high flexibility were prepared on stainless steel meshes (SSMs). The improved photovoltaic responses of CBS-GNs and ZTO/CBS-GNs with the incorporation of graphene nanoplatelets were determined using surface photovoltage spectroscopy (SPS). The signals of time-resolved fluorescence response (TFR) and transient surface photovoltage (TPV) can provide more detailed information on the transition, separation and transport of photogenerated carriers.

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Here, Zn2SnO4 nanorods/Cu4Bi4S9 (ZTO/CBS) and ZTO nanorods/CBS-graphene nanosheets (ZTO/CBS-GNs), as well as two types of bulk heterojunction (BHJ) solar cells with high flexibility were fabricated on stainless steel meshes (SSMs). The excellent photovoltaic responses of CBS-GNs and ZTO/CBS-GNs with incorporation of GNs were determined using surface photovoltage spectroscopy (SPS). The signals of time-resolved fluorescence response (TFR) and transient surface photovoltage (TPV) can provide more detailed information for transition, separation, and transport of photoinduced carriers.

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BiFeO(3) (BFO) microspheres were synthesized by a facile hydrothermal method. The optical absorption spectrum indicates that on site Fe(3+) crystal-field transitions and the charge transfer excitations can be observed. Magnetic measurements show a spin-glass behavior and room temperature weak ferromagnetism.

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