Extensively studied Mn-doped semiconductor nanocrystals have invariably exhibited photoluminescence over a narrow energy window of width ≤150  meV in the orange-red region and a surprisingly large spectral width (≥180  meV), contrary to its presumed atomic-like origin. Carrying out emission measurements on individual single nanocrystals and supported by ab initio calculations, we show that Mn P...

Metal–oxide–semiconductor capacitor structure with metal nanocrystals embedded in the gate oxide for the application of nonvolatile memory (NVM) is fabricated. Optimal process parameters are investigated and Au nanocrystals are adopted in this paper. High-frequency capacitance versus voltage (C–V ) and conductance versus voltage (G–V ) measurements demonstrate the memory effect of the structure...

The charge retention characteristics of metal nanocrystal (MNC) and semiconductor nanocrystal (SNC) memory devices are comparatively studied in this paper. A charge retention model is proposed, taking into account the quantum confinement effect, to account for the better retention characteristics of metal nanocrystal memory observed in the experiment. Simulation results are in good agreement wi...

Doped and undoped ZnS semiconductor nanocrystals having different recombination pathways are explored to study the charge transfer reaction between the nanocrystals and the 4-nitrophenol/sodium borohydride redox couple.

Doping of semiconductors by impurity atoms enabled their widespread technological application in microelectronics and optoelectronics. However, doping has proven elusive for strongly confined colloidal semiconductor nanocrystals because of the synthetic challenge of how to introduce single impurities, as well as a lack of fundamental understanding of this heavily doped limit under strong quantu...

Au/ZnS core/shell nanocrystals with controllable shell thicknesses were synthesized using a cysteine-assisted hydrothermal method. Incorporating Au/ZnS nanocrystals into the traditional Pt-catalyzed half-cell reaction led to a 43.3% increase in methanol oxidation current under light illumination, demonstrating their promising potential for metal/semiconductor hybrid nanocrystals as the anode ph...

Conventional organic fluorophores suffer from poor photo stability, narrow absorption spectra and broad emission spectra. Semiconductor nanocrystals, however, are highly photo-stable with broad absorption spectra and narrow size-tunable emission spectra. Recent advances in the synthesis of these materials have resulted in the generation of bright, sensitive, extremely photo-stable and biocompat...

We synthesize colloidal CdSe@CdS octapod nanocrystals decorated with Pt domains, resulting in a metal-semiconductor heterostructure. We devise a protocol to control the growth of Pt on the CdS surface, realizing both a selective tipping and a non-selective coverage. Ultrafast optical spectroscopy, particularly femtosecond transient absorption, is employed to correlate the dynamics of optical ex...

Semiconductor nanocrystals are tiny light-emitting particles on the nanometer scale. Researchers have studied these particles intensely and have developed them for broad applications in solar energy conversion, optoelectronic devices, molecular and cellular imaging, and ultrasensitive detection. A major feature of semiconductor nanocrystals is the quantum confinement effect, which leads to spat...

The combination of upconversion nanocrystals with a wide-bandgap semiconductor is an efficient strategy to develop near-infrared (NIR)-responsive photocatalysts. The photocatalytic activity of the hybrid structures is greatly determined by the efficiency of the energy transfer on the interface between upconversion nanocrystals and the semiconductor. In this work, we demonstrate the interface de...