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In this work, Ag nanoparticles were deposited in the TiO${}_{2-X}$ nanotube films through magnetron sputtering to form Ag-TiO${}_{2-X}$ nanocomposite. Scanning electron microscopy (SEM) was used to study microstructure and surface morphology. Rhodamine B (RhB) was deposited on the surface of Ag-TiO${}_{2-X}$ substrate for Raman spectroscopy test. The size of Ag nanoparticles can be controlled by changing the magnetron sputtering time. The result indicated that sputtering for 30 s obtained the highest Raman enhancement.

In this work, Ag nanoparticles were deposited on quartz glass substrates by magnetron sputtering method, and the morphology was characterized by SEM. Ag nanoparticle surface plasmon resonance characteristics were observed by transmittance measurement. The experimental results demonstrated an increase in particle size that was correlated to an increase in sputtering time and a plasmon resonance absorption peak redshift. This phenomenon was partially explained by Mie scattering model. The differences between our theoretical analysis and experimental results show that both the shape of and the spacing between nanoparticles are key parameters affecting plasmon resonance peak location.

In this paper, Ag nanoparticles were successfully prepared by chemical reduction, and then Ag/ZnO composite particles were successfully prepared and deposited onto glass substrates to form Ag/ZnO thin films. Hereafter, the structure, the morphology and the metal enhanced fluorescence (MEF) property of Ag nanoparticles and ZnO/Ag composite particles were studied by XRD, SEM, EDS, TEM, UV-vis absorption and fluorescence (FL) spectrometer. The results showed that the average size of Ag nanoparticles increased with the increase of prepared time. Moreover, ZnO layer consisted of polycrystalline structure and amorphous interface layer, but nano-Ag particle was polycrystalline structure. Annealing process was carried out to investigate the influence of annealing process parameters on MEF property of Ag/ZnO composite structure. Due to annealing treatment, the amorphous component of Ag/ZnO thin films was reduced, which might improve the density of Ag/ZnO thin films and the diameter of composite particles. Furthermore, FL enhancement phenomenon of fluorescein isothiocyanate (FITC) molecules might be attributed to the joint influence of the roughness and the density of these films and the average diameter of composite particles.

We have synthesized highly stable silver nanoparticles in aqueous solution at room temperature by standard reduction method using bovine serum albumin (BSA) as a stabilizing agent. The nonlinear optical properties of nanoparticles were investigated using Z-scan technique at 532 nm. The obtained nonlinear absorption coefficient and negative nonlinear refractive index is found to be 88.36 cm/GW and -5.1 × 10^-7 esu respectively. The real and imaginary part of third order susceptibility of silver nanoparticles is found to be 1.553 × 10^-7 esu and 0.7 × 10^-7 esu respectively. The silver nanoparticles in BSA template show good optical limiting property.

An electrostatic-force-directed-assembly technique was used to coat multiwalled carbon nano-tubes (MWCNTs) with aerosol Ag nanoparticles produced from a mini-arc plasma source. The deposition of Ag nanoparticles onto CNTs was confirmed by transmission electron microscopy (TEM), high-resolution TEM, scanning electron microscopy, and X-ray photoelectron spectroscopy. Ripening of Ag nanoparticles on CNTs was observed via successive TEM imaging after heating the nanoparticle–nanotube hybrid structures in air to three different temperatures ranging from 100°C to 300°C. With temperatures at and above 200°C, the areal density of Ag nanoparticles decreased and the average particle size increased. In particular, migration and coalescence of Ag nanoparticles have been observed at this relatively low temperature, which suggests a van der Waals nanoparticle–nanotube interaction.

Large-area GaN-based blue light-emitting diodes (LEDs) on sapphire substrates with an omnidirectional nanostructure consisted of Ag nanoparticles and TiO₂/SiO₂ Bragg reflector were fabricated. For the LEDs without the omnidirectional nanostructure, the spectra of the P- and S-polarization light are lightly different and the peak wavelength of P- and S-polarization light was estimated to be 464 nm and 463 nm, respectively at forward current of 20 mA. In contrast, for the LEDs with the omnidirectional nanostructure, the spectra of the P- and S-polarization light are nearly the same at forward current of 20 mA and 100 mA.

A series of monodisperse Ag nanoparticles (Ag NPs), whose size can be tuned between 2 nm and 34 nm, have been successfully synthesized in one pot by controlling the growth time. The standard deviation of the small-size Ag NPs is 12% while that of the large-size ones is 15%. During the synthesis process, sodium borohydride and sodium dodecyl sulfate were used as reducing agent and surfactant, respectively, and the effect of the synthesis parameters on the size-tuning range and the size distribution of Ag NPs was studied to get the optimum growth condition. Moreover, surface enhanced Raman scattering (SERS) spectra were analyzed to explore the synthesis mechanism of Ag NPs.

Ag nanoparticles were deposited by polyol process onto the as-synthesized anatase TiO₂ cubes with single crystals by hydrothermal method. The materials were characterized by SEM, XRD, TEM, XPS and UV-vis spectroscopy and their photoconversion efficiencies were also evaluated. The photocurrent measurements revealed that the modification of the anatase TiO₂ cubes with Ag nanoparticles improved the photoelectrochemical properties of electrodes.

Ag nanoparticles (Ag NPs) embedded carbon nanofibers (CNFs) were prepared by a new route which included chemical reaction process, electrospinning and calcination technique. The morphology and structure of the composite nanofibers were investigated by scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy and X-ray diffraction. It indicated that Ag NPs were uniformly distributed in the CNFs. This effective synthesis method can be used to prepare other composite nanofibers with functionality. The Ag NPs/CNFs that served as supported catalysts were used in the styrene epoxidation by TBHP. The Ag NPs/CNFs catalyst showed its highly catalytic activity for the epoxidation of styrene (conversion: 40.6%, SO selectivity: 35.9%). This kind of composite nanofiber membrane was proved effectively catalytic activity and recycled easily in the styrene epoxidation.

Ag pillared interlayered clays (Ag-PILCs) were synthesized through a novel method, in which Ag nanoparticles were formed in montmorillonite interlayers. In this method, silver ions were first exchanged into montmorillonite interlayers, and then reduced into Ag nanoparticles by trisodium citrate at 100°C in aqueous solutions. The synthesized Ag@montmorillonite nanocomposite was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM), and its surface area was evaluated by using Brunauer–Emmet–Teller (BET) method. Compared to traditional PILCs synthesized through ion exchange method, the formed Ag-PILCs had better thermal stability and stronger structure because their pillars are nanoparticles. Furthermore, this method introduces a possibility to control the size of the pillars and thus the pore size of the PILCs, due to that the nanoparticle pillars can be modified on their forms and diameters in the synthesizing process. Also, it was found that the intercalating Ag nanoparticle pillars were formed at restricted pH values and silver ion concentrations.

A novel composite nanostructure which is made up of TiO₂ three dimensionally ordered macroporous (3DOM) nanostructure and TiO₂ nanorods (NRs) has been successfully synthesized through a combination of colloidal crystal template technology and hydrothermal method, then we achieved its combination with Ag nanoparticles (NPs) via a silver mirror reaction. We studied the SERS (Surface-Enhanced Raman Scattering) performance of the obtained structure, the results show that our samples are very sensitive substrates when being used to detect dye R6G molecules, with a low detection concentration of 10${}^{-11}$ M. This proves that it is a promising material in the area of analyzing and molecule-level detecting as a kind of novel and low-cost SERS substrate.

An efficient and stable catalyst was prepared utilizing reduced graphene oxide, Ag nanoparticles and melamine sponge for the restoration of large volume effluent containing 4-nitrophenol at room temperature. And the as-prepared sample is suitable for continuous flow system. Almost 99% 4-nitrophenol ($1.0\times 10^{-4}$molL${}^{-1}$, 100mL) can be removed within 4min in the presence of the aforementioned sample. Moreover, it also exhibits remarkable stability in continuous flow system. This may offer a new route to the fabrication of efficient flowing catalytic system.

Ag nanoparticles decorated N-doped carbon black with different Ag content was synthesized via a straightforward method. The catalysts have been conducted in the catalytic hydrogenation of nitrophenols in the presence of sodium borohydride. The results show that Ag₄/NCB possesses the highest catalytic activity for the catalytic hydrogenation of $p$-nitrophenol ($p$-NP) to $p$-aminophenol ($p$-AP). The significant enhancement in catalytic activity can be attributed to the high dispersity and smaller size of Ag nanoparticles, and remarkable synergistic effect of the combination of Ag nanoparticles and N-doped carbon black.

4-nitrophenol (4-NP) is a highly toxic pollutant for aquatic ecosystem and human life. Therefore, the catalytic reduction of 4-NP into useful 4-aminophenol (4-AP) is of interest. In this regard, two heterogeneous nanocatalysts, including Ag@HNTs-ILs and Co@HNTs-ILs were prepared by grafting imidazolium-based ionic liquids (ILs) onto the halloysite nanotubes (HNTs), followed by immobilization of Ag and Co nanoparticles (NPs), and characterized by means of FT-IR, SEM, EDX, TEM and XRD. The catalytic activity of the prepared nanocatalysts was evaluated for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) under environmentally friendly condition. A set of time, temperature, nanocatalyst amount and NaBH₄/4-NP molar ratios was screened. The reusability experiments demonstrated that Ag@HNTs-ILs and Co@HNTs-ILs were highly reusable, up to five reduction cycles without considerable changes in the reaction time. As the synthesized hybrid nanocatalysts could be re-collected and reused for various catalytic runs without any significant loss in their catalytic activity, they could be considered very promising nanomaterials from sustainability point of view.

In this study, we synthesized graphic carbon nitride nanosheets (labeled as CNs) by solid-phase grinding strategy coupled calcination method and then prepared Ag nanoparticles (NPs) loaded CNs composites by photodeposition. The as-prepared Ag/CNs composites presented remarkably enhanced photocatalytic performance and the degradation rate of tetracycline (TC) by Ag/CNs (3wt.%) composite is above two times higher than that by pristine CNs under visible light irradiation. The enhanced photocatalytic activity originated from the close contact between Ag and CNs, and the localized surface plasmon resonance (LSPR) effect of Ag. Moreover, the results of radical trapping experiments illustrated that $\cdot {\mathrm{\text{O}}}_2^{-}$ plays a dominant role in photocatalytic degradation of TC. This work provides a new way for design novel noble metal modified graphic CN photocatalysts.

Ag nanoparticles were synthesized and stabilized on a polymeric support, poly($N$-isopropyl acrylamide-co-itaconic acid)/POSS, by simply reducing Ag${}^{+}$ ions adsorbed in the interior of the polymeric network. The prepared Ag@p(NIPAM-IA)/POSS was used as an efficient and recyclable catalyst for removal of the 4-nitrophenol (4-NP) contaminant by NaBH₄-induced reduction to 4-aminophenol (4-AP) in aqueous solution. Different conditions including Ag content and amount of the nanocomposite, and also temperature of the 4-NP reduction were investigated. Also, two kinetic models, zero-order and first-order kinetics, were studied for the reduction of 4-NP to 4-AP.

Due to their distinctive optical potential, controlled plasmonic features, control over size and shape, and ability to manipulate their localized surface plasmon resonance (LSPR) and their response to their surroundings, silver nanoparticle attracts special attention in the fields of the biosensor. Silver (Ag) is an appealing tool in many domains, including diagnosis, medicine delivery, environment, electronics, and as an antibacterial agent. Ag nanoparticle applications are ubiquitous today in the fields of biosensors. Numerous studies have demonstrated the effectiveness of using Ag nanoparticles to improve the specific detection of clinical indicators. The development of nanotechnology has greatly benefited the field of biosensors since nanomaterials have a high surface-to-volume ratio that enables them to operate with greater sensitivity and effectiveness. Utilizing interdisciplinary study in biology, chemistry, and material science, recent advancements in nanotechnology encouraged the manufacture of nanomaterials in a variety of shapes and sizes. In the context of disease diagnosis, this review highlighted the use of Ag nanoparticles in biosensors to detect small molecules to bigger entire cells. This paper also discusses how to make a glucose biosensor more sensitive. It describes how the detection performance of biomolecules including DNA, protein, tiny molecules, and complete cells can be improved. For future applications in the field of diagnosis, this review helps in developing an overall understanding of the clinical importance of Ag nanoparticles. These biosensors can be implemented in the field of diagnosis to speed up the response time.