Irreversible optical sensing of humidity by a doped cholesteric liquid crystal is achieved by using a thin film of nematic host E7 with a binaphthylorthosilicate ester as dopant (guest). The film changes its color from blue (to green to orange to red) to colorless when exposed to humidity as the dopant is hydrolyzed.

Both Fe3 + and Fe2 + ions occur in FeCl3-doped polyacetylene. At low dopant levels ( < 0.01 mole frac­ tion) both Fe2 + and Fe3 + io'ns are paramagnetic down to 4.2 K. At dopant levels > 0.01 mole fraction, there is evidence from Mossbauer spectroscopy that Fe2+ ions associate into aggregates which are magneti­ cally ordered below 25 K. Aggregate formation appears to correlate with high electri...

It is now possible to create atomically thin regions of dopant atoms in silicon patterned with lateral dimensions ranging from the atomic scale (angstroms) to micrometers. These structures are building blocks of quantum devices for physics research and they are likely also to serve as key components of devices for next-generation classical and quantum information processing. Until now, the char...

We report on an extensive spectroscopic investigation of the impact of substitutional doping on the optoelectronic properties of PbS colloidal quantum dot (CQD) solids. N-doping is provided by Bi incorporation during CQD synthesis as well as post-synthetically via cation exchange reactions. The spectroscopic data indicate a systematic quenching of the excitonic absorption and luminescence and t...

The controlled introduction of dopant atoms to semiconducting host materials is the corner stone of electronic device fabrication. Dopant atoms provide a means to modulate the electronic, optical, and magnetic properties of semiconductors [1], and it is now possible to control dopant profiles with true atomic-scale precision in the laboratory [2]. Moreover, industrial fabrication methods are no...

Bimetallic metal-organic frameworks are rationally synthesized as templates and employed for porous carbons with retained morphology, high graphitization degree, hierarchical porosity, high surface area, CoNx moiety and uniform N/Co dopant by pyrolysis. The optimized carbon with additional phosphorus dopant exhibits excellent electrocatalytic performance for the oxygen reduction reaction, which...

To overcome the thermal instability of a p-doped organic hole transporting layer using the state-of-the-art p-type dopant, 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane, a potent electron accepter, 3,6-difluoro-2,5,7,7,8,8-hexacyanoquinodimethane, has been found to possess superior thermal stability and proved to be an excellent p-type dopant.

In this work, we report on the effects of doping SnO2 nanoparticles with Zn 2+ ions. A series of ~23nm sized Sn1xZnxO2 crystallite samples with 0 ≤ x ≤ 0.18 were synthesized using a forced hydrolysis method. Increasing dopant concentration caused systematic changes in the crystallite size, oxidation state of Sn, visible emission and band gap of SnO2 nanoparticles. X-ray Diffraction (XRD) studie...

The rapid population growth and economic development have largely contributed to environmental pollution. Various advanced oxidation processes been used as the most viable solution for reduction of recalcitrant pollutants wastewater treatment. Heterogeneous photocatalysis is one broadly technologies treatment among all processes. Graphitic carbon nitride alone or in combination with various oth...

in the present study, co-zno and co-ni-zno nanoparticles were synthesized by sonochemical methods and the structural and optical properties were investigated through fourier transform infrared spectroscopy (ftir), uv-vis spectroscopy, field emission scanning electron microscopy (fe-sem), x-ray diffraction (xrd), and photoluminescence spectroscopy (pl) methods. morphology of nanoparticles obtain...