查找使用阿拉丁产品的科研文献

A Wide-Range, Highly Stable Intelligent Flexible Pressure Sensor Based on Micro-Wrinkled SWCNT/rGO-PDMS with Efficient Thermal Shrinkage

Lei Fan,Zhaoxin Wang,Tao Yang,Qiang Zhao,Zhixin Wu,Yijie Wang,Xue Qi,Lei Zhang

Flexible pressure sensors have drawn growing attention in areas like human physiological signal monitoring and human–computer interaction. Nevertheless, it still remains a significant challenge to guarantee their long-term stability while attaining a wide detection range, a minute pressure testing limit, and high sensitivity. Inspired by the wrinkles on animal skins, this paper introduces a flexible pressure sensor with wrinkled microstructures. This sensor is composed of a composite of reduced graphene oxide (rGO), single-walled carbon nanotubes (SWCNTs), and polydimethylsiloxane (PDMS). After optimizing the proportion of the composite materials, the flexible pressure sensor was manufactured using highly efficient heat-shrinkable films. It has a sensitivity as high as 15.364 kPa−1. Owing to the wrinkled microstructures, the sensor can achieve an ultra-wide pressure detection range, with the maximum reaching 1150 kPa, and is capable of detecting water wave vibrations at the minimum level. Moreover, the wrinkled microstructures were locked by PDMS. The sensor acquired waterproof performance and its mechanical stability was enhanced. Even after 18,000 cycles of repeated loading and unloading, its performance remained unchanged. By combining with an artificial neural network, high-precision recognition of different sounds and postures when grasping different objects was realized, with the accuracies reaching 98.3333% and 99.1111%, respectively. Through the integration of flexible WIFI, real-time wireless transmission of sensing data was made possible. In general, the studied sensor can facilitate the application of flexible pressure sensors in fields such as drowning monitoring, remote traditional Chinese medicine, and intelligent voice.

A highly sensitive EC-SERS sensor of PANI/RGO/Ag/Cu film for doubly detecting glyphosate residues in fresh fruit

Xishun Peng,Yiheng Yuan,Anjiang Lu,Cunwei Wang,Caizhen Zu,Haili Zhang,Zhongchen Bai

Glyphosate (Gly) residues in agricultural products have a serious health risk, so it is urgent to seek a sensitive and convenient method for recognizing Gly residues in food. In this study, we proposed an electrochemical surface-enhanced Raman spectroscopy (EC-SERS) sensor of polyaniline/reduced graphene oxide/Ag/Cu (PANI/RGO/Ag/Cu) film to detect Gly residues. The EC-SERS sensor of PANI/RGO/Ag/Cu film had a large specific surface area, which could increase the binding sites of cu 2+ /Gly clathrates for boosting specifically its SERS signal. Moreover, Ag/Cu nanoparticles on the surface of film could effectively increase the differential pulse voltammetry signal and SERS signal of Gly molecules. The limit of detection of EC-SERS sensor to Gly could reach 1.9 nM. In addition, the EC-SERS sensor we prepared could also sensitively identify Gly residues on fresh fruit peels. The PANI/RGO/Ag/Cu film we proposed in this paper has great potential for selective and accuracy detecting Gly residues in agricultural products.

One-Step Preparation of an AgNP-nHA@RGO Three-Dimensional Porous Scaffold and Its Application in Infected Bone Defect Treatment

Weizong Weng,Xiaoqun Li,Wei Nie,Haoyuan Liu,Shanshan Liu,Jianming Huang,Qirong Zhou,Jia He,Jiacan Su,Zhifeng Dong,Dongliang Wang

Urchin-like hierarchical CoZnAl-LDH/RGO/g-C3N4 hybrid as a Z-scheme photocatalyst for efficient and selective CO2 reduction

Yong Yang,Jiajia Wu,Tingting Xiao,Zheng Tang,Jinyou Shen,Haijin Li,Yong Zhou,Zhigang Zou

A unique urchin-like CoZnAl-LDH/RGO/g-C 3 N 4 (LDH/RGO/CN) Z-scheme photocatalyst, which is fabricated by the hydrothermal synthesis of CoZnAl-LDH and the in situ loading of RGO and g-C 3 N 4 , is developed for the photocatalytic conversion of CO 2 . The special spiny external surface and hollow inner cavity endow LDH/RGO/CN with a significantly enhanced light-harvesting capacity. The well-distributed g-C 3 N 4 nanosheets on the CoZnAl-LDH nanoplates, combined with RGO as an electron mediator, constructs an excellent heterosystem with numerous interfaces, efficient charge separation and highly exposed catalytic active sites. The Z-scheme charge-transfer process promotes the oxidizability and reducibility of CoZnAl-LDH and g-C 3 N 4 . Furthermore, the synergistic effect among the components contributes to intense adsorption and chemical activation towards CO 2 , which reduces the reaction barrier for CO 2 photoreduction. As a result, the optimized LDH/RGO/CN exhibits highly efficient and selective photocatalytic CO 2 conversion to CO. The special 3D urchin-like architecture paves a new way for design of photocatalyst with ideal performance.

One-pot hydrothermal fabrication of BiVO4/Fe3O4/rGO composite photocatalyst for the simulated solar light-driven degradation of Rhodamine B

Zhao Shuangyang,Chen Chengxin,Ding Jie,Yang Shanshan,Zang Yani,Ren Nanqi

Fabrication of easily recyclable photocatalyst with excellent photocatalytic activity for degradation of organic pollutants in wastewater is highly desirable for practical application. In this study, a novel ternary magnetic photocatalyst BiVO 4 /Fe 3 O 4 /reduced graphene oxide (BiVO 4 /Fe 3 O 4 /rGO) was synthesized via a facile hydrothermal strategy. The BiVO 4 /Fe 3 O 4 with 0.5 wt% of rGO (BiVO 4 /Fe 3 O 4 /0.5% rGO) exhibited superior activity, degrading greater than 99% Rhodamine B (RhB) after 120 min solar light radiation. The surface morphology and chemical composition of BiVO 4 /Fe 3 O 4 /rGO were studied by scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, UV visible diffuse reflectance spectroscopy, Fourier transform infrared spectroscopy, and Raman spectroscopy. The free radicals scavenging experiments demonstrated that hole (h + ) and superoxide radical (O 2 •− ) were the dominant species for RhB degradation over BiVO 4 /Fe 3 O 4 /rGO under solar light. The reusability of this composite catalyst was also investigated after five successive runs under an external magnetic field. The BiVO 4 /Fe 3 O 4 /rGO composite was easily separated, and the recycled catalyst retained high photocatalytic activity. This study demonstrates that catalyst BiVO 4 /Fe 3 O 4 /rGO possessed high dye removal efficiency in water treatment with excellent recyclability from water after use. The current study provides a possibility for more practical and sustainable photocatalytic process.

Highly active rGO/Ca-MOF loaded Pd-M (M = Fe, Sb, Pb, Sn, Ag) composite catalysts towards ethylene glycol electrooxidation

Yuting Zhong,Zhirui Wu,Xiaoguang Liu,Ling Li

The combination of multi-metallic alloys and support materials is a promising approach for the design of electrocatalysts. In this study, Pd-M (M = Fe, Sb, Pb, Sn, Ag) bimetallic alloys embedded composites of 2D Ca-based metal–organic framework (Ca-MOF) nanosheets and reduced graphene oxide (rGO) were fabricated by a facile hydrothermal and impregnation reduction method, then applied as ethylene glycol oxidation reaction (EGOR) electrocatalysts. Remarkably, the forward peak current density of the best catalytic performer PdAg@rGO/Ca-MOF is as high as 258.30 mA cm −2 , which is 9.55 times greater than that of Pd/C. It also exhibits the biggest electrochemical active surface area of 3022.51 m 2 g −1 . After 3600 s chronoamperometry test, the retained current density of PdAg@rGO/Ca-MOF is about 87.94 % of the initial current density. These results imply that bimetallic Pd-M@rGO/Ca-MOF have superior electrocatalytic activity and anti-CO poisoning capacity compared to monometallic and Pd/C for EGOR, especially PdAg@rGO/Ca-MOF. The enhanced EGOR performance is due to the combined effect of Pd-M alloys and folded thin layer wrapped nanosheet rGO/Ca-MOF composites.

Hydro-thermal preparation of PbCO3/N-rGO nano-composites as positive additives to improve the performance of lead-acid batteries

Kai-da Zhu,Xin-ru Wang,Jing Zhong,Sen-lin Wang

Due to the expansion of the energy storage market, the demand for lead-acid batteries is also increasing. In order to improve the discharge specific capacity of lead-acid batteries, this paper uses graphene oxide (GO), Pb(Ac) 2 ·3H 2 O, urea and other raw materials in the reactor. The PbCO 3 /N-rGO nanocomposite was prepared by a hydrothermal method as a positive electrode additive for lead-acid batteries. The material was characterized by XRD, STM , SEM, Raman, etc., and was doped into a simulated battery positive plate. The positive plate exhibits excellent electrochemical performance when the addition amount of the PbCO 3 /N-rGO nanocomposite in the positive plate is 1 wt%. In the simulated battery test, the initial discharge specific capacity reaches 166 mAh g −1 , which is 52% higher than that of the blank control group, and a 2-fold improvement in HPRSoC cycle life at 1 C rate. The PbCO 3 /N-rGO enabled the battery to have a higher discharge specific capacity and the longest charge/discharge cycle life, this is due to the nanostructure and good electrical conductivity of the PbCO 3 /N-rGO nanocomposite improving the utilization of the positive active material (PAM).

Knowledge-aided automated analysis of dielectric loss mechanism on core-shell VN@N-rGO nanobelts with broadband microwave absorption performance

Yanfeng Li,Linyue Hu,Wenmiao Wang,Pan Luo,Yang Yang,Huacheng Zhu,LiPing Yan,Yanping Zhou

Understanding the microwave dissipation mechanisms in materials is essential for the design of high-performance absorbers. Previous studies in this field have largely relied on a single-order Debye model combined with nonlinear least squares (NLLS) fitting, under the assumption of frequency-independent conductivity. However, this approach presents several limitations, including limited applicability to composite materials, inaccuracies in conductivity estimation, high sensitivity to initial guesses, and challenges in determining relaxation times. To address these issues, a multi-order Debye model that integrates Jonscher's power-law dielectric response, thereby establishing a frequency-dependent relationship for conductivity, is developed as the analytical framework. Subsequently, a distribution of relaxation times (DRT) method with Tikhonov regularization is developed to extract polarization relaxation times, with its parameter optimized based on the materials' physicochemical properties. Furthermore, a genetic algorithm (GA)-assisted NLLS fitting procedure is implemented for complex permittivity modeling, which facilitates escape from local minima and improves the likelihood of finding global optima. Dielectric analysis of the synthesized VN@N-rGO core-shell nanobelts indicates a significant synergy between the components, enhancing both conductive and polarization losses. The hybridization increases the equivalent dipole relaxation times of N-rGO, thereby aligning them more closely with the period of 2–18 GHz microwaves and thus improving polarization loss. By optimizing the VN/N–rGO ratio and layer structure, an effective absorption bandwidth of 7.7 GHz is achieved at 2.1 mm.

Simultaneous detection of ascorbic acid, dopamine, and uric acid using an rGO/PE/PVP@ HPMC/GCE electrode in biological matrices

Al Kiey Sherief A.,Baseer Rasha A.,Kamel Samir

The simultaneous detection of ascorbic acid (AA), dopamine (DA), and uric acid (UA) is crucial for biomedical and clinical diagnostics. Herein, we present a highly sensitive and selective electrochemical sensor based on a modified glassy carbon electrode (GCE) functionalized with hydroxypropyl methylcellulose (HPMC), polyvinylpyrrolidone (PVP), and 3D reduced graphene oxide/pentaerythritol (3D rGO/PE). The structural and morphological properties of the composite were characterized using Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM). Electrochemical analysis demonstrated the remarkable electrocatalytic activity of 3D rGO/PE/PVP@HPMC/GCE for the oxidation of AA, DA, and UA, with peak potential separations of 214, 133, and 346 mV for DA-AA, DA-UA, and UA-AA, respectively. Under optimized conditions, the sensor exhibited wide linear detection ranges of 4.0 µM to 1.0 mM (AA), 0.2–100 µM (DA), and 1.0–100 µM (UA), with detection limits of 0.82, 0.002, and 0.025 M, respectively. The sensor demonstrated excellent sensitivity, selectivity, reproducibility, and stability, making it a promising platform for real-sample analysis.

Two-step reduction of self-assembed three-dimensional (3D) reduced graphene oxide (RGO)/zinc oxide (ZnO) nanocomposites for electromagnetic absorption

Fan Wu,Yilu Xia,Yuan Wang,Mingyang Wang

Graphene oxide (GO) and zinc oxide (ZnO) nanoparticles have formed a three-dimensional (3D) nanocomposite through a hydrothermal process, and further UV-irradiation removed the remaining oxygen functional groups from the skeleton of the reduced graphene oxide (RGO). This new type of 3D-RGO/ZnO nanocomposite exhibits a wide and effective absorption bandwidth (deeper than −10 dB), which was characterized as 6.4 GHz when the filler loading is 10 wt% in the composite and the thickness of the absorber is 2.5 mm. Therefore, combining the GO and ZnO nanoparticles into a 3D nanocomposite can be considered as an effective route to design a light weight and high performance electromagnetic absorption material.

Enhanced sulfur redox kinetics and polysulfide regulations with petal-like nickel hydroxide nanosheets/rGO modified separators in Li-S batteries

Changfeng Zhao,Xiaoxia Yang,Guang Xia,Jinglei Liu,Wenqian Zhang,Jie Xue,Shifeng Hou,Cheng Hu

Li-S batteries have been regarded as one of the most prospective energy-storage systems because of its high-energy-density. To suppress the shuttling effect of dissolved lithium polysulfides, different mass ratios petal-like nickel hydroxide nanosheets (NHN) decorated reduced graphene oxide (rGO) materials are synthesized in this study using a one-step hydrothermal method and applied modified separators in Li-S batteries. With up to 73.5 wt% of sulfur content in the cathode, the optimized sample (the mass ratio of graphene oxide to nickel nitrate is 1:9) enables discharge capacities up to 1579 mAh g −1 at 0.2 C (the areal sulfur loading is 5 mg cm −2 ). The cell also exhibits a retention of 840 mAh g −1 in specific capacity after 200 cycles, exhibiting higher utilizations and better cycling stabilities for Li-S batteries. Electrochemical measurements and density functional theory (DFT) calculations prove that NHN plays a critical role in promoting the redox reaction kinetics of Li-S batteries, and the high conductivity of rGO enhances the electrochemical function of NHN. This study provides a low cost approach for the developments of modified separators in future practical Li-S batteries.

Interfacial Engineering on Cathode and Anode with Iminated Polyaniline@rGO-CNTs for Robust and High-Rate Full Lithium–Sulfur Batteries

Meng Li,Hao Chen,Can Guo,Shangshu Qian,Hongpeng Li,Zhenzhen Wu,Chao Xing,Pan Xue,Shanqing Zhang

Lithium–sulfur batteries (LSBs) currently suffer from severe polysulfide shuttling, slow redox kinetics at the sulfur cathode, and irreversible dendrite growth at the lithium anode. To address these issues, a dual interfacial engineering strategy on both the cathode and anode is proposed. For the cathode, iminated polyaniline (iPANI) is used to achieve energetic engineering to induce mid-energy level to the adsorption of polysulfides, and catalyze the redox conversion of sulfur species, and realize morphological engineering via self-assembly of iPANI onto a scaffold integrated by reduced graphene oxide (rGO) and carbon nanotubes (CNTs), namely iPANI@rGO-CNTs. For the anode, the highly conductive and lithiophilic nature and porous nanostructure of the iPANI@rGO-CNTs composite facilitates the uniform deposition of lithium-ions, significantly preventing the growth of lithium dendrites. Density functional theory calculations suggest that the iminated functional group at the excited state in iPANI can significantly suppress the shuttling effect, catalyze the conversion of sulfur species, and enhance the conversion of the sulfur species on the sulfur cathode. With the synergic effects of the iPANI@rGO-CNTs nanoreactors, the as-prepared LSBs deliver an excellent rate capability and outstanding cycling life. This large-scale production and application of the iPANI@rGO-CNTs nanocomposite may lead to the eventual commercialization of LSBs.