查找使用阿拉丁产品的科研文献

Study on the Performance and Mechanism of Ag-Bi4Ti3O12 Composite Photocatalyst for Oxygen Production by Water Oxidation

Canwen Liu,Lin Zhou,Wenxue Wang,Yang Zhang,Su Zhan,Feng Zhou

Photocatalytic water splitting for clean energy production holds significant practical potential in addressing the global energy crisis. However, the oxygen evolution reaction (OER) remains the primary bottleneck in overall efficiency due to its kinetically sluggish and complex four-electron transfer process. Bi4Ti3O12 theoretically meets the reaction conditions of OER because of its high valence band value and unique layered structure formed by alternately stacking perovskite layers [Bi2Ti3O10]2– and bismuth oxide layers [Bi2O2]2+. However, its application in OER is limited due to its unsatisfactory charge distribution, poor separation efficiency, and low selectivity for O2. Therefore, the Ag-Bi4Ti3O12 composite photocatalyst was prepared by photodeposition. The Schottky barrier between the n-type semiconductor Bi4Ti3O12 and the noble metal Ag can be used as an effective charge transfer channel. This can alter the surface charge distribution and space charge separation efficiency of Bi4Ti3O12, prevent the selective generation of hydroxyl radicals, further enhance its product selectivity to O2, and raise Bi4Ti3O12’s OER efficiency. The results show that the OER rate of Bi4Ti3O12 after Ag loading is obviously improved, which is about twice that of unmodified Bi4Ti3O12. The research results of this work will provide research ideas for the design of efficient OER catalysts.

MOF derived Ag₂S/ZnIn₂S₄@TiO₂@carbon composite with enhanced photocatalytic performance for degradation of tetracycline

Ye Zhang,Xiaobing Yang

Recently, the overuse of tetracycline (TC) has caused persistent adverse effects on both ecological environment and human health. It needs to develop effective methods for removing TC from water. Herein, Ag 2 S/ZnIn 2 S 4 @TiO 2 @carbon was successfully synthesized and used as catalyst for degradation of TC. The influence of Ag 2 S and ZnIn 2 S 4 on the photocatalytic activity of TiO 2 @carbon were investigated. The results show that the Ag 2 S/ZnIn 2 S 4 @TiO 2 @carbon achieved a photocatalytic degradation efficiency of 98.73 %. Moreover, the photocatalytic activity of Ag 2 S/ZnIn 2 S 4 @TiO 2 @carbon remained nearly unchanged after four consecutive cycles, with only a 3.2 % decrease in degradation efficiency. Finally, the degradation mechanism of TC over Ag 2 S/ZnIn 2 S 4 @TiO 2 @carbon was elucidated.

The impacts of green synthetized 0-to 3-dimentional Ag nanostructures on polyspecies microbial biofilms and dermocompatibility

Qiongyi Huang,Wenjing Xie,Peiyao Liu,Qingwei Yu,Jingying Li,Xinyu Wei,Chunying Jiang,Peixuan Tan,Ding Cao,Ying Tang

Green synthetized Ag nanoparticles are increasingly used as antimicrobial agents topically applied to human skin for sanitization and medical purposes. Despite the widespread use, little was known on their antibiofilm efficacy and dermocompatibility. This study reports a systematic investigation into the impacts of green synthetized 0–3D Ag nanostructures, including 0D nanospheres, 1D nanowires, 2D nanoprisms and 3D nanoflowers as well as Ag nanospheres modified by different phytochemicals, on anti-biofilm efficacy and biocompatibility at the nano-skin interface. It was revealed that varying the Ag morphology induces distinct effects on two established polyspecies models consisting of skin-borne microbes ( S. aureus-S. epidermidis and S. aureus-C. albicans ). Ag nanospheres and nanowires are advantageous in inhibiting the formation of early biofilms (47–61 %) while Ag nanoprisms and nanoflowers are more effective in destroying mature biofilms (68–70 %). ROS-mediated oxidative stress, physical damage to cell membrane integrity, “contact killing” of microbial cells and suppression of adhesion-related gene expression are mechanisms involved in the anti-biofilm actions of these green synthetized Ag nanostructures. Furthermore, the dermocompatibility assessments were performed in reconstructed human epidermis. Although all exposed epidermis models remained > 50 % tissue viability, more Ag nanospheres were transdermally adsorbed than other morphologies while Ag nanoprisms were shown to be more cytotoxic. These findings provide insights into the impacts of 0–3D green synthetized Ag nanostructures on skin-borne polyspecies biofilms and dermocompatibility at the nano-skin interface, highlighting the importance of taking morphology and phytochemical modification into consideration for the rational design of sustainable Ag-based antimicrobials tailored for topical applications.

Solid-state voltammetry-based electrochemical immunosensor for Escherichia coli using graphene oxide–Ag nanoparticle composites as labels

Xiaochun Jiang,Kun Chen,Jing Wang,Kang Shao,Tao Fu,Feng Shao,Donglian Lu,Jiangong Liang,M. Frahat Foda,Heyou Han

A new electrochemical immunosensor based on solid-state voltammetry was fabricated for the detection of Escherichia coli (E. coli) by using graphene oxide–Ag nanoparticle composites (P-GO–Ag) as labels. To construct the platform, Au nanoparticles (AuNPs) were first self-assembled on an Au electrode surface through cysteamine and served as an effective matrix for antibody (Ab) attachment. Under a sandwich-type immunoassay format, the analyte and the probe (P-GO–Ag–Ab) were successively captured onto the immunosensor. Finally, the bonded AgNPs were detected through a solid-state redox process in 0.2 M of KCl solution. Combining the advantages of the high-loading capability of graphene oxide with promoted electron-transfer rate of AuNPs, this immunosensor produced a 26.92-fold signal enhancement compared with the unamplified protocol. Under the optimal conditions, the immunosensor exhibited a wide linear dependence on the logarithm of the concentration of E. coli ranging from 50 to 1.0 × 106 cfu mL−1 with a detection limit of 10 cfu mL−1. Moreover, as a practical application, the proposed immunosensor was used to monitor E. coli in lake water with satisfactory results.

Hierarchical Ag-SiO2@Fe3O4 magnetic composites for elemental mercury removal from non-ferrous metal smelting flue gas

Yongpeng Ma,Bailong Mu,Xiaojing Zhang,Hongzhong Zhang,Haomiao Xu,Zan Qu,Li Gao

Hierarchical Ag-SiO 2 @Fe 3 O 4 magnetic composites were selected for elemental mercury (Hg 0 ) removal from non-ferrous metal smelting flue gas in this study. Results showed that the hierarchical Ag-SiO 2 @Fe 3 O 4 magnetic composites had favorable Hg 0 removal ability at low temperature. Moreover, the adsorption capacity of hierarchical magnetic composite is much larger than that of pure Fe 3 O 4 and SiO 2 @Fe 3 O 4 . The Hg 0 removal efficiency reached the highest value as approximately 92% under the reaction temperature of 150°C, while the removal efficiency sharply reduced in the absence of O 2 . The characterization results indicated that Ag nanoparticles grew on the surface of SiO 2 @Fe 3 O 4 support. The large surface area of SiO 2 supplied efficient reaction room for Hg and Ag atoms. Ag–Hg amalgam is generated on the surface of the composites. In addition, this magnetic material could be easily separated from fly ashes when adopted for treating real flue gas, and the spent materials could be regenerated using a simple thermal-desorption method.

A plasmonic nano-sensor for the fast detection of Ag+ based on synergistic coordination-inspired gold nanoparticle

Jianjun Du,Hong Du,Haoying Ge,Jiangli Fan,Xiaojun Peng

Silver is one of most important heavy metals, which affects the environment and organism significantly along with its widespread applications. An interesting gold nanoparticles (AuNPs)-based system, in this work, was fabricated using the adenosine and creatinine for the colorimetric recognition of the Ag + via a red-to-blue color change. A synergistic coordination of these two biomolecules with Ag + on AuNPs’ surface supplied an excellent selectivity than examples by a single ligand-modified AuNPs in literatures. It realized a qualitative Ag + recognition by naked eyes in aqueous media, as well as a quantitative determination by the UV–vis spectrometer over a range of 0.1–0.9   μM, covering the Ag + standard in drinking waters (0.46   μM, US Environmental Protection Agency). This system is not only convenient but also very sensitive with a limit detection of 7.3   nM. This platform is applicable for the Ag + recognition in mimic pollution samples with a good repeatability and relative standard deviation.

Improving the emission of ultrasmall Mn-doped ZnInS quantum dots via Ag-induced trap state energy level

Guangguang Huang,Chunlei Wang,Shuhong Xu,Yiping Cui

For ultrasmall Mn-doped quantum dots (QDs), the energy transfer of the exciton to the Mn is the key factor for Mn emission. Herein, the Ag-induced electron trap state energy level, which is an intermediate energy level between the conduction band (CB) and 4T1 of Mn, is proposed for improving the energy transfer. After doping the Ag and forming Ag&Mn:ZnInS QDs, most excitons will first be captured by the intermediate energy level and then be transferred to Mn d-states, leading to enhanced photoluminescence (PL) quantum yields (QY) of the QDs from the original 17% (Mn:ZnInS QDs) to 30% (Ag&Mn:ZnInS QDs).

Ag Nanowires Embedded ZnO for Semitransparent Organic Solar Cells with 13.76% Efficiency and 19.09% Average Visible Transmittance

Lingling Zheng,Ming Li,Shijie Dai,Yinghao Wu,Yuhang Cai,Xinyu Zhu,Shaokun Ma,Daqin Yun,Jian-Feng Li

In recent years, semitransparent organic solar cells (ST-OSCs) receive more and more attention due to their applications in building-integrated photovoltaics. There is a complicated trade-off between the average visible transmittance (AVT) and the power conversion efficiency (PCE), which determine the overall light utilization efficiency (LUE) of ST-OSCs. In this work, the ST-OSCs are fabricated using ZnO as the buffer layer between an ultrathin metal electrode and an active layer of PM6:Y7. Moreover, Ag nanowires (Ag NWs) are embedded into ZnO film to increase the conductivity without serious loss of AVT. The LUE improves to 2.63% with a PCE of 13.76% and an AVT of 19.09% for ST-OSC with modification. Significant enhancement of the short-circuit current density and electrical property of the device is attributed to the excellent conductivity, the scattering effect, and the surface plasmon resonance of Ag NWs. This study provides an efficient strategy to fabricate high-performance ST-OSCs with high LUE.

Stretchable conductive elastomer composites based on a processing of Ag+ swelling, in situ reduction, and drying shrinkage

Tianze Wang,Yuping Liu,Meijiao Guo,Guang-xin Chen,Qifang Li

We present a simple preparation method for the stretchable conductive nanocomposites which can still maintain the activity and electrical stability under the condition of large-scale mechanical processing. The preparation scheme takes advantage of the swelling mechanism of the polymer and introduces the precursor silver ions into it. A reducing agent is then incorporated into the polymer matrix , and the silver ions in the polymer matrix are reduced in situ to form silver nanoparticles . Drying the solvent inside of the polymer causes the polymer to spontaneously shrink, resulting in the tight accumulation of silver nanoparticles . Subsequent experimental tests show that the prepared composite material stretched to its original swelling state still retains its high conductivity. When the content of silver reaches the saturation value , its maximum conductivity is 2500 S/cm, and its high conductivity at 80% deformation is retained. The composite material also shows certain fatigue resistance .

Nano Ag-enhanced photoelectric conversion efficiency in all-inorganic, hole-transporting-layer-free CsPbIBr2 perovskite solar cells

Youming Huang,Yizhi Wu,Xiaoliang Xu,Feifei Qin,Shihan Zhang,Jiakai An,Huijie Wang,Ling Liu

All-inorganic, hole-transporting-layer-free CsPbIBr2 perovskite solar cells have great potential for development, but their device performance needs to be further improved. Recently, metal nanostructures have been successfully applied in the field of solar cells to improve their performance. Nano Ag-enhanced power conversion efficiency (PCE) in one CsPbIBr2 perovskite solar cell utilizing localized surface plasmons of Ag nanoparticles (NPs) on the surface has been researched experimentally and by simulation in this paper. The localized surface plasmon resonance of Ag NPs has a near-field enhancement effect, which is expected to improve the light absorption of CsPbIBr2 perovskite photovoltaic devices. In addition, Ag NPs have a forward-scattering effect on the incident light, which can also improve the performance of CsPbIBr2-based perovskite photovoltaic devices. By directly assembling Ag NPs (with a size of about 150 nm) on the surface of fluorine-doped tin oxide it is found when the particle surface coverage is 10%, the CsPbIBr2 perovskite photovoltaic device achieves a best PCE of 2.7%, which is 9.76% higher than that of the control group. Without changing any existing structure in the ready-made solar cell, this facile and efficient method has huge applications. To the best of our knowledge, this paper is the first report on nano Ag-enhanced photoelectric conversion efficiency in this kind of CsPbIBr2 perovskite solar cell.

1O2-Mediated Selective Oxidation of 5-hydroxymethylfurfural to 2,5-diformylfuran by Ag/Ag3PO4 under Visible Light Irradiation

Rui Zhu,Xinglong Li

Graphical A photocatalytic selective oxidation strategy for preparing DFF from HMF is developed, using Ag/Ag 3 PO 4 as the photocatalyst and O 2 as the oxidizing agent. In contrast to previous photocatalytic oxidation strategies for HMF transformation, this catalytic system could efficiently generate 1 O 2 without other ROS under visible light irradiation. DFF would be obtained with 88 % selectivity with the optimal reaction conditions. The synthesis of 2,5-diformylfuran (DFF) through photocatalytic oxidation of 5-hydroxymethylfurfural (HMF) is an attractive approach. In this manuscript, a photocatalytic selective oxidation strategy for HMF was developed, using Ag/Ag 3 PO 4 as the photocatalyst and O 2 as the oxidizing agent. The prepared catalyst was characterized systematically by SEM, XRD, XPS, UV-Vis, PL spectra, and so on. In contrast to previous photocatalytic oxidation strategies for HMF conversion, this catalytic system could efficiently generate 1 O 2 without other reactive oxygen species (ROS) under visible light irradiation. DFF would be obtained with about 90 % selectivity. Moreover, the exclusive formation of 1 O 2 was linked to the more positive conduction band potential (+0.90 eV) of Ag/Ag 3 PO 4 , confirmed by an array of characterization techniques. Additionally, the stability of the catalyst was assessed through cyclic testing and analyses including XRD, and XPS. Nonetheless, this catalytic system could potentially serve as a robust platform for various selective oxidation reactions in the future, due to its exclusive presence of 1 O 2 without the involvement of other ROS.

Critical Addition Point-Based Trace Sensing of Hg²+ Through Surface Plasma Polaritons Properties Analysis of Ag Nanoparticles

Xia Zhang,Yu-Ying Wang,Ya-Nan Xu,Meng-Xiao Xu,Hua-Ling Zhang,Guan-Xi Li