Publications

A Sliding-Mode Triboelectric Nanogenerator with Chemical Group Grated Structure by Shadow Mask Reactive Ion Etching

The sliding-mode triboelectric nanogenerator (S-TENG) with grated structure has important applications in energy harvest and active sensors; however its concavo-convex structure leads to large frictional resistance and abrasion. Here, we developed a S-TENG with a chemical group grated structure (S-TENG-CGG), in which the triboelectric layer's triboelectric potential has a positive–negative alternating charged structure. The triboelectric layer of the S-TENG-CGG was fabricated through a reactive ion etching process with a metal shadow mask with grated structure. In the etched region, the nylon film, originally positively charged as in friction with stainless steel, gained opposite triboelectric potential and became negatively charged because of the change of surface functional groups. The output signals of the S-TENG-CGG are alternating and the frequency is determined by both the segment numbers and the moving speed. The applications of the S-TENG-CGG in the charging capacitor and driving calculator are demonstrated. In the S-TENG-CGG, since there is no concavo-convex structure, the frictional resistance and abrasion are largely reduced, which enhances its performances in better stability and longer working time.

Tribo-electrophoresis preconcentration enhanced ultra-sensitive SERS detection

Kinetically Controlled Growth and Shape Formation Mechanism of Platinum Nanoparticles

Recently, we have been able to synthesize platinum colloidal nanoparticles of different shapes (Science, 1996, 272, 1924). In this report, we present transmission electron microscopic (TEM) results on the time-dependent shape distribution of platinum nanoparticles during the growth period and its dependence on the concentration of the capping polymer as well as the pH of the solution. The results suggest a shape-controlled growth mechanism in which the difference between the rate of the catalytic reduction process of Pt2+ on the {111} and {100} faces, the competition between the Pt2+ reduction and the capping process on the different nanoparticle surfaces, and the concentration-dependent buffer action of the polymer itself all control the final distribution of the different shapes observed.

Carbon nanoparticle-assisted natural orifice specimen extraction surgery with left colic artery preservation: a retrospective study

Natural orifice specimen extraction surgery (NOSES) has been widely regarded as a new technology in minimally invasive surgery. Meanwhile, carbon nanoparticles have been increasingly used for lymph node tracing in colorectal cancer surgery.To evaluate the effectiveness and feasibility of carbon nanoparticle-assisted natural orifice specimen extraction surgery with left colic artery preservation for total laparoscopic colorectal resection.We retrospectively reviewed the medical records of 83 patients diagnosed with sigmoid colon cancer or mid- and upper-rectal cancer from October 2017 to June 2020. These patients were divided into the NOSES group who underwent left colic artery preservation NOSES, being injected with a carbon nanoparticle suspension under colonoscopy the day before surgery, and the LA group, who underwent left colic artery preservation laparoscopic surgery. Surgical outcomes were retrospectively analyzed.The mean number of harvested lymph nodes (p < 0.001) in the NOSES group was higher than in the LA group. Conversely, as regards pain score (p < 0.001) and postoperative hospital stay (p = 0.035), the LA group has higher mean values. The incidence of perioperative complications (p = 0.385) was 5.3% for the NOSES group compared to 13.3% for the LA group.Preoperative colonoscopic injection of a carbon nanoparticle suspension is a feasible and practical solution to dissect lymph nodes surrounding the inferior mesenteric artery without affecting the left colic artery in patients with colorectal cancer and about to receive NOSES. Moreover, NOSES combined with this approach leads to less postoperative pain and shorter hospital stays.

Anomalous Growth and Coalescence Dynamics of Hybrid Perovskite Nanoparticles Observed by Liquid-Cell Transmission Electron Microscopy

We report on in situ observations of nucleation, growth, and aggregation of hybrid organic–inorganic perovskites by liquid-cell transmission electron microscopy. Direct crystallization of hybrid CH3NH3PbI3 nanoparticles is achieved through an electron beam-assisted solvent evaporation approach. Time-lapse liquid-cell TEM imaging of the nanoparticles reveals a growth trend which is not entirely consistent with the classical Lifshitz–Slyozov–Wagner growth model. Significantly complex dynamical behaviors are observed during the coalescence process of CH3NH3PbI3 nanoparticles. We propose that the chemical instability inherent in the hybrid perovskite iodides should be considered to understand this phenomenon in addition to the oriented attachment mechanism. This study provides a useful reference for understanding the intriguing chemical and physical properties of hybrid organic–inorganic perovskites.

Single‐Crystal Hexagonal Disks and Rings of ZnO: Low‐Temperature, Large‐Scale Synthesis and Growth Mechanism

Solution-phase synthesis of single-crystal ZnO disks and rings was achieved in high yield at low temperature (70–90 °C) by using an anionic surfactant as a template. The reaction can be controlled by means of the growth temperature and the molar ratio of reagents to favor formation of disks or rings. A growth mechanism is proposed on the basis of structural information provided by SEM and TEM.

Compressible hexagonal-structured triboelectric nanogenerators for harvesting tire rotation energy

The shape evolution of gold seeds and gold@silver core–shell nanostructures

We report the seed-dependent shape evolution of gold@silver (Au@Ag) core–shell nanostructures with various morphologies through using pre-existing Au nanocrystals as nuclei in a polyvinylpyrrolidone (PVP)-assisted polyol reduction process. Au nanocrystalline seeds with different shapes such as cube, truncated-octahedron, octahedron, twinned hexagon and triangle, five-twinned decahedron and nanorod are firstly synthesized by refluxing a 1,5-pentanediol solution containing Au precursors in the presence of PVP. The Au seeds obtained in this way then serve as the nuclei for further epitaxial growth of Ag shells by using Ag precursors via the same route. Scanning transmission electron microscope (STEM) characterization of the products obtained demonstrates that the morphological evolution of the Ag shells depends completely on the shapes of the Au seeds that are used. We have observed that the Au@Ag core–shell nanostructures formed with various regular shapes such as cube, bi-triangle, and nanorod with five-twinned cross section, are mostly surrounded by {100}-type Ag crystalline facets. Our findings provide new evidence and clear evolution routines from the Au cores with well-defined shapes to the corresponding Ag shells for the Au@Ag core–shell nanostructures by the family of the PVP-assisted polyol reduction methods.

Berberine-Loaded Nanostructured Lipid Carriers Enhance the Treatment of Ulcerative Colitis

Triboelectric Nanogenerator Built on Suspended 3D Spiral Structure as Vibration and Positioning Sensor and Wave Energy Harvester

An unstable mechanical structure that can self-balance when perturbed is a superior choice for vibration energy harvesting and vibration detection. In this work, a suspended 3D spiral structure is integrated with a triboelectric nanogenerator (TENG) for energy harvesting and sensor applications. The newly designed vertical contact-separation mode TENG has a wide working bandwidth of 30 Hz in low-frequency range with a maximum output power density of 2.76 W/m(2) on a load of 6 MΩ. The position of an in-plane vibration source was identified by placing TENGs at multiple positions as multichannel, self-powered active sensors, and the location of the vibration source was determined with an error less than 6%. The magnitude of the vibration is also measured by the output voltage and current signal of the TENG. By integrating the TENG inside a buoy ball, wave energy harvesting at water surface has been demonstrated and used for lighting illumination light, which shows great potential applications in marine science and environmental/infrastructure monitoring.

Silk fibroin-based biodegradable piezoelectric composite nanogenerators using lead-free ferroelectric nanoparticles

Laser-Tunable Noncontact Triboelectric Nanogenerators: A Novel Approach for Surface Charge Regulation and Enhanced Lifetime

The output performance of triboelectric nanogenerators (TENGs) largely depends on the density of electrons on the surface of the triboelectric materials, which is usually generated by the direct contact of two solid materials. Here, a novel method is proposed to regulate the surface charges of materials without physical contact. A laser-tunable noncontact triboelectric nanogenerator (LTNC-TENG) is fabricated, enabling the dynamic regulation of the surface states of materials through laser irradiation to optimize the performance of TENGs. In the experiment, TiO₂, SiO₂, and VO₂ LTNC-TENGs are designed and prepared. The results show that under low-energy laser irradiation, the open-circuit voltage (<i>V</i>_OC) and short-circuit transferred charge (<i>Q</i>_SC) increase, primarily due to the enhancement of the surface state energy levels induced by laser irradiation. As the laser energy increases beyond the laser-induced damage threshold (LIDT) of the films, induced damage occurs, generating abundant high-temperature plasma and resulting in decreased <i>V</i>_OC and <i>Q</i>_SC. Building upon these findings, a single-electrode mode LTNC-TENG is developed where voltage jumps occur when laser energy exceeds the film's LIDT. Furthermore, an electron cloud-potential well model is proposed, describing the approach of atoms from two different materials under laser irradiation without direct contact. This model elucidates the detailed mechanism of laser-induced charge transfer and reveals the "precursor" process of contact electrification. This study contributes to a deeper understanding of the underlying mechanisms of contact electrification and provides a theoretical foundation for the development of more advanced and noncontact TENGs, with largely enhanced lifetime.

Flexible and Transparent Nanogenerators Based on a Composite of Lead‐Free ZnSnO₃ Triangular‐Belts

A flexible and transparent lead-free triangular-belt ZnSnO3 nanogenerator is demonstrated. When a mechanical deformation of ≈0.1% is applied to the triangular-belt ZnSnO3 nanogenerator, the output voltage and current reached 5.3 V and 0.13 μA, respectively, which indicated a maximum output power density of ≈11 μW·cm−3. This is the highest output power that has been demonstrated by lead-free ZnSnO3 triangular-belts. Detailed facts of importance to specialist readers are published as "Supporting Information". Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Sustainable high-voltage source based on triboelectric nanogenerator with a charge accumulation strategy

Sustainable high-voltage TENG (SH-TENG) based on charge accumulation strategy can provide an unprecedented high voltage output.

Direct Growth of TiO₂ Nanosheet Arrays on Carbon Fibers for Highly Efficient Photocatalytic Degradation of Methyl Orange

Anatase TiO2 sheets with exposed high-energy (001) facets are grown on carbon fibers (CFs) by a facile hydrothermal synthetic route. The percentage of reactive facets in the TiO2 nanosheets (NSs) is calculated to vary between about 40% and 92%, depending on the synthesis conditions. In comparison with TiO2 NSs grown on a planar substrate, the TiO2 NS/CF hybrid structure exhibits a 3.38-fold improvement in photocatalytic degradation of methyl orange under UV-light irradiation.

Host plant defenses of black (<i>Solanum nigrum</i> L.) and red nightshade (<i>Solanum villosum</i> Mill.) against specialist <i>Solanaceae</i> herbivore <i>Leptinotarsa decemlineata</i> (Say)

Abstract Black nightshade ( Solanum nigrum, S. nigrum L.) and red nightshade ( Solanum villosum, S. villosum Mill.) are medicinal plants from the Solanaceae family that synthesize glycoalkaloids and other secondary metabolites. To recognize the potential insecticide activity of these compounds, leaf extracts (containing glycoalkaloid and methanol fractions) were tested for enzyme inhibition, antifeedant activity and toxicity. For in‐vitro glutathione S‐transferase (GST) inhibition activity, we used insecticide‐resistant Colorado potato beetle, Leptinotarsa decemlineata ( L. decemlineata ; Say) midgut and fat‐body homogenate. In‐vivo toxicity and the antifeedant activity were performed using larval bioassays. The methanol extracts had greater GST inhibitory activity compared to the glycoalkaloids, as well as greater 2nd instar larvae mortality and antifeedant activity. Furthermore, the green leaf volatile compound, cis‐hex‐3‐enyl acetate, at the concentration of 5 ppm, caused 50% mortality of 2nd instar larvae. Our findings suggest the potential usefulness of S. nigrum and S. villosum extracts to control L. decemlineata .

SiO₂/Ta₂O₅ Core—Shell Nanowires and Nanotubes.

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

Evolutionary trend analysis of nanogenerator research based on a novel perspective of phased bibliographic coupling