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Electrodeposition of Ternary Semiconductors
Published in R.K. Pandey, S.N. Sahu, S.N. Sahu, S. Chandra, Handrook Of Semiconductor Electrodeposition, 2017
R.K. Pandey, S.N. Sahu, S.N. Sahu, S. Chandra
Two ternary semiconductors based on CdTe, CdHgTe and CdZnTe, have been electrodeposited. The cadmium mercury telluride in particular has received considerable attention due to its application in infrared detectors and photovoltaics. Its band gap can be tailored by controlling the Cd/Hg stoichiometry. This property can be used for the design and fabrication of high-efficiency tandem structures with the bottom cell made from CdHgTe. Another advantage with CdHgTe is the relative ease of forming contacts over it compared to CdTe. The band gap of CdxHg1-xTe is related to the stoichiometric composition term x by the relation Eg(eV)=-0.303+1.984x-0.654x2+0.579x3+10-4T(5.5-13.92x+5.8x2)
Towards chemical imaging: Fourier transform infrared mapping on organo-mineral materials
Published in European Journal of Environmental and Civil Engineering, 2018
T. Bonnal, G. Foray, E. Prud’homme, S. Tadier
An infrared microscope NicoletTM from Thermo Scientific was used with a Cadmium Mercury Telluride (MCT) type A linear array sensor cooled with liquid nitrogen. OMNICTM software was used to acquire spectra. An area of 6025 × 2500 μm² was imaged by specular reflection with a 25 × 25 μm² resolution (Figure 2(a)). All data pre-treatment and deconvolution techniques have been realised using a homemade algorithm encoded on MATLAB R2015a.
Recent advances on fluorescent biomarkers of near-infrared quantum dots for in vitro and in vivo imaging
Published in Science and Technology of Advanced Materials, 2019
Shanmugavel Chinnathambi, Naoto Shirahata
CdTe and HgTe QDs are most widely used in the NIR region. Gao et al. developed CdTexSe1– x/ZnS alloy nanocrystals to achieve QYs up to 80% with controllable rod-shape and NIR (λem = 650–870 nm) emission (Figure 2(a)) [21]. He et al. reported a facile one-step microwave synthesis of water-soluble CdTe QDs. The water-soluble NIR CdTe QDs (λem = 700–800 nm) are used first time for in vivo tumor targeting and also used for in vitro imaging after conjugation with protein molecules (Figure 2(b,d,f)) [22]. Recently, Geiregat et al. demonstrated that mercury telluride (HgTe) QDs exhibit size-tunable emission all over the NIR window at thresholds unmatched by any QDs studied before (Figure 2(c)) [23]. Alloyed CdTe1−xSex/CdS NIR QDs are used for detecting pancreatic cancer in mouse models [24]. Alloyed CdHgTe QDs were prepared via heating a mixture of Cd2+, Hg2+, and Te2- in the presence of 3-mercaptopropionic acid (MPA) as ligands with photoluminescence (PL) QYs (20–50%) and narrow emission bands and it will be a suitable fluorescent probe in the imaging of living animals [25]. Recently, Liu et al. developed a NIR-emitting CdHgTe/CdS/CdZnS QDs and coated them with three different thiol ligands, 3-MPA, thioglycolic acid (TGA), and N-acetyl-L-cysteine (NAC). In vivo toxicity measurement shows negligible harmful effects to nude mice even at a concentration of 20 mg kg−1 [26]. Gadolinium-functionalized CdHgTe/ZnS core/shell QDs are used for in vivo fluorescence and magnetic resonance imaging [27]. Cyclic arginine-glycine-aspartic acid conjugated micelle-encapsulated NIR CdTe/ZnSe QDs as highly luminescent probes for bio-labeling and in vivo imaging of pancreatic tumor in live mice [28]. In 2011, CdTe/CdSe QDs were also successfully applied for the fluorescence imaging of living animals (Figure 2(e)) [29].