Metal nanocrystals offer new concepts for the design of nanodevices with a range of potential applications. Currently the formation of metal nanocrystals cannot be controlled at the level of individual atoms. Here we describe a new general method for the fabrication of multi-heteroatom-doped graphitic matrices decorated with very small, ångström-sized, three-dimensional (3D)-metal crystals of d...

Silica xerogels containing Sm ions and SnO2 nanocrystals were prepared in a sol–gel process. The image of transmission electron microscopy (TEM) shows that the SnO2 nanocrystals are dispersed in the silica matrix. The X-ray diffraction (XRD) of the sample confirms the tetragonal phase of SnO2. The xerogels containing SnO2 nanocrystals and Sm 3+ ions display the characteristic emission of Sm ion...

Here we present a facile one-pot method to prepare high-quality CdTe nanocrystals in aqueous phase. In contrast to the use of oxygen-sensitive NaHTe or H(2)Te as Te source in the current synthetic methods, we employ more stable sodium tellurite as the Te source for preparing highly luminescent CdTe nanocrystals in aqueous solution. By selecting mercaptosuccinic acid (MSA) as capping agent and p...

Enhanced Faraday effect of cube-shaped EuS nanocrystals (average crystal size = 12 nm) with a coercive field is demonstrated for the fast time. The coercive field and the remanent magnetization of cube-shaped EuS nanocrystals were found to be 0.011 T and 0.05 μB, respectively, using a SQUID (superconducting quantum interface device). Consideration of the volume percentages of cube-shaped EuS na...

We report the enhancement of both visible and near infrared (NIR) emissions from Nd(3+) ions via Ce(3+) sensitization in colloidal nanocrystals for the first time. This is achieved in citrate capped Nd(3+)-doped CeF3 nanocrystals under ultraviolet (UV) irradiation (λex = 282 nm). The lasing transition ((4)F3/2 → (4)I11/2) at 1064 nm from Nd(3+)-doped CeF3 nanocrystals has much higher emission i...

Concerns over possible toxicities of conventional metal-containing quantum dots have inspired growing research interests in colloidal silicon nanocrystals (SiNCs), or silicon quantum dots (SiQDs). This is related to their potential applications in a number of fields such as solar cells, optoelectronic devices and fluorescent bio-labelling agents. The past decade has seen significant progress in...

The composition and morphology of nanocrystals in urines of healthy persons and lithogenic patients were comparatively investigated by means of X-ray diffraction (XRD) and transmission electron microscopy (TEM). It was shown that the main composition of urinary nanocrystals in healthy persons were calcium oxalate dihydrate (COD), uric acid, and ammonium magnesium phosphate (struvite). However, ...

Highly luminescent, manganese doped, zinc sulphide (ZnS:Mn) nanocrystals biofunctionalized with chitosan and various aminoacids such as L-citrulline, L-lysine, L-arginine, L-serine, L-histidine and glycine were synthesized by chemical capping co-precipitation method at room temperature, which is a simple and cost effective technique. The synthesized nanocrystals were structurally characterized ...

Monodisperse lanthanide oxyfluorides LnOF (Ln = Gd, Y) with mid-infrared emissions were controllably synthesized via a mild co-precipitation route and a subsequent heat-treatment. The detailed composition and morphology were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and high resolution transmission electron microscopy (HRTEM). The results showed that monodispe...

The shape control of gold nanocrystals has attracted extensive research interest because of their unique shape-dependent properties and widespread applications. Surfactants have been frequently used in the shape-controlled synthesis of gold nanocrystals in solution. In this feature article, we summarize some of the emerging colloidal approaches towards shape-tailored gold nanocrystals with the ...