Silica aerogels functionalized with strongly fluorescent carbon quantum dots were first prepared and used for simple, sensitive, and selective sensing of NO2 gas. In the presence of ethanol, homemade silica aerogels with a large specific surface area of 801.17 m(2)/g were functionalized with branched polyethylenimine-capped quantum dots (BPEI-CQDs) with fluorescence quantum yield higher than 40...

nanotechnology has slowly but steadily revolutionized the diagnosis, imaging and treatment of cancer. detecting cancer at earliest stages, locating the tumor at different areas in the body and specific delivery of the drugs to malignant cells including surgically inaccessible tumors are the core areas of medical and pharmaceutical research across the world. in this endeavour, nanodevices have e...

The fragmentation of fullerenes using ions, surface collisions or thermal effects is a complex process that typically leads to the formation of small carbon clusters of variable size. Here, we show that geometrically well-defined graphene quantum dots can be synthesized on a ruthenium surface using C(60) molecules as a precursor. Scanning tunnelling microscopy imaging, supported by density func...

In this paper, we present calculations for different parameters of quantum dot infrared photodetectors. We considered a structure which includes quantum dots with large conduction-band-offset materials (GaN/AlGaN). Single band effective mass approximation has been applied in order to calculate the electronic structure. Throughout the modeling, we tried to consider the limiting factors which dec...

the present work deals with the synthesis and characterization of cds nanoparticles with good thermal stability and optical properties by a novel and simple synthetic route. the nanoparticles were synthesized via chemical precipitation method in a single reaction vessel under ambient conditions. the prepared cds nanoparticles were compared with the bulk cds. the optical properties were determin...

Electrodes based on graphite, graphene, and carbon nanomaterials have been used in the anode chamber of microbial fuel cells (MFCs). Carbon quantum dots (C-dots) are a class of versatile nanomaterials hitherto not reported in MFCs. C-dots previously synthesized from coconut husk were reported to possess hydroxyl and carboxyl functional groups on their surface. The presence of these functional g...

quantum dots of cds with hexagonal phase were prepared at relatively low temperature (60 oc) and short time by micro-emulsion (o/w) under ultrasound. this study was focused on the particle size distribution and the growth kinetics. the particle size distribution obtained from the optical absorption edge. it was relatively symmetrical with sonication time. in addition, an agreement was observed ...

the electronic conductance at zero temperature through a quantum wire with side-connected asymmetric quantum ring (as a scatter system) is theoretically studied using the non-interacting hamiltonian anderson tunneling method. in this paper we concentrate on the configuration of the quantum dot rings. we show that the asymmetric structure of qd-scatter system strongly influences the amplitude an...