查找使用阿拉丁产品的科研文献

Roles of oxygen vacancy and Ox− in oxidation reactions over CeO2 and Ag/CeO2 nanorod model catalysts

Houlin Wang,Shuting Luo,Meisheng Zhang,Wei Liu,Xiaodong Wu,Shuang Liu

Though the catalytic oxidation of CO, NO and soot over CeO 2 could be understood within a similar Mars-van Krevelen-type mechanism, these reactions were likely to be driven by different active phases. In this work, several CeO 2 and Ag/CeO 2 nanorods with different contents of surface oxygen vacancies (V O-s ) and active oxygen species (O x − ) were designed as model catalysts. Their catalytic performance indicated that, CO oxidation was determined by pre-existing ceria V O-s , while O x − participated in NO and soot oxidation directly. Besides, by loading silver onto the high-temperature aged CeO 2 nanorods, Ag/CeO 2 catalysts with high availability of ceria lattice oxygen were obtained, whose low-temperature oxidation activity was proven comparable to that of the platinum catalysts. In this sense, the model designing in this work not only provided methods to find out proper reactivity descriptors, but also conferred low-cost catalysts with high practical potential.

Efficient Photoinduced Thermocatalytic Chemiluminescence System Based on the Z-Scheme Heterojunction Ag3PO4/Ag/Bi4Ti3O12 for H2S Sensing

Jiaxi Hu,Hongjie Song,Cheng Chen,Lichun Zhang,Mingxia Sun,Yi Lv

Cataluminescence as a highly efficient gas transduction principle has attracted wide attention among research in environmental monitoring and clinical diagnosis with increasing awareness of human safety. Nowadays, the development of innovation sensing systems and the construction of the sensing mechanism to improve the analytical performance of compounds remain a major challenge. Herein, we construct an advanced photoinduced thermocatalytic chemiluminescence (PI-TC-CL) gas-sensing system via the introduction of a Z-scheme heterojunction Ag3PO4/Ag/Bi4Ti3O12 to achieve higher efficient detection of H2S. The unique electron transport path of the Z-scheme heterojunction and the LSPR effect of Ag nanoparticles fascinate the generation of the photoinduced electron–hole pair on the surface of catalysts when stimulated by LED lamps and slow down the recombination of electron–hole pairs under thermal conditions. Thus, based on the cooperative effect of the Z-scheme heterojunction AgPO/Ag/BTO and PI-TC-CL system, we have successfully established an efficient H2S CTL detection system, which has a response three times higher than that on the traditional CTL system and even 45 times higher than that on BTO and ranges among the best of the state-of-the-art CTL performance in H2S detection with the linear range of 0.095–8.87 μg mL–1 and a limit of detection of 0.0065 μg mL–1. Besides, to explore the gas-sensing mechanism, the synergetic effects of photoinduction and thermal catalysis are investigated thoroughly via conductivity and electrochemical experiments. This research provides a new perspective of engineering highly efficient catalysts and ingenious sensor systems through designing the nanostructure of materials and synergism catalytic mechanism.

Enhanced thermal performance of phase-change material supported by nano-Ag coated eggplant-based biological porous carbon

Chuge Zhang,Xiaowu Hu,Shikun Xiao,Wenxing Luo,Haozhong Wang,Xiongxin Jiang

In this paper, nano-Ag coated eggplant-based biological porous carbon (BPC) was used as the support material to load PEG to solve the problem of leakage and low thermal conductivity of phase change material (PCM). A series of support materials (caky BPC, caky BPC@Ag, BPC powders, BPC@Ag powders) were prepared. The results show that the shape-stabilized PCM (ss-PCM) obtained by caky BPC had better anti-leakage ability. The thermal conductivity of the support material coated with nano-Ag particles was increased by 40.9 % compared with the uncoated support material. After ten thermal cycles, the composite ss-PCM (ss-CPCM) remained to exhibited excellent thermal reliability, which indicated that the ss-CPCM supported by nano-Ag coated BPC had excellent potential in practical application. In addition, BPC@Ag improved the light-to-heat conversion rate and had more application prospects. In addition, BPC had a high photo-thermal conversion efficiency, and BPC@Ag further improved the photo-thermal conversion.

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.

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.

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

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 .

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).

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.

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.

Synthesis of Ag NPs layer and its application as SERS substrate in the determination of p-phenylenediamine

Yu Qizhi,Kong Xiangfa,Chen Chaoshu,Kang Caiyan,Meng Mianwu,Huang Siyu

An Ag nanoparticles (NPs) layer was synthesized on Ag sheet by alloying/electrochemical dealloying method: X-ray diffraction confirmed that the new Ag phase appeared after removing Ga from Ag-Ga alloy, and scanning electron microscopy examination showed that the prepared Ag layer had a NPS structure. The fine microstructure of silver resulted in significant SERS enhancement effect, while the NPs layer was used as the SERS substrate: when the prepared NPs layer was used as a SERS substrate to detect p-phenylenediamine (PPD), it exhibited a strong SERS peak at 1590 cm −1 . The result revealed that the intensity of SERS peaks was linear to the logarithm of PPD concentration in the range from 10 −16 mol L −1 to 10 −12 mol L −1 and the detection limit was 1.0 × 10 −17 mol L −1 .