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Enhancement of Cd(II) Adsorption on Microalgae?Montmorillonite Composite
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Nutrient alterations following biochar application to a Cd-contaminated solution and soil
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Molecular basis of CD-NTase nucleotide selection in CBASS anti-phage defense
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Enhanced Cd(II) biomineralization induced by microalgae after cultivating modification in high-phosp
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Bandgap engineering of Cd 1 - x Zn x Te 1 - y Se y ( 0 < x < 0 . 27 , 0 < y < 0 . 026 )
CdZnTe (CZT) detectors with more than 10% zinc content did not show a remarkable improvement in the detector performance due to the additional defects introduced by the higher zinc content. However, recent research showed that the formation of defects was suppressed effectively by adding a small amount of selenium (2%) in CZT. On this basis, we attempted to enhance the detector performance through bandgap engineering by increasing the zinc content up to 25 %, while adding 2 % of selenium. Multiple CdZnTeSe (CZTS) ingots with Zn = 10, 12.5, 15, 20 and 25%, while fixing the Se composition at 2%, were grown by the Bridgman method. The bandgap of CZTS for the different Zn and Se contents was analyzed and then equations for predicting the bandgap for other alloy compositions were introduced. Furthermore, the crystallinity of CZTS was evaluated by photoluminescence measurements. The pulse height spectra for Am-241 and Co-57 sources were used to evaluate the detector performance for the CZTS samples.
Carbonate Coprecipitation for Cd and Zn Treatment and Evaluation of Heavy Metal Stability Under Acidic Conditions
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High Mobility Cd 3 As 2 (112) on GaAs(001) Substrates Grown via Molecular Beam Epitaxy
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Negative Thermal Expansion in the Noncarboxylate Based Metal–Organic Framework Cd(trz)Cl
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Bandgap Tunable Ternary Cd$_x$Sb$_{2–y}$S$_{3−δ}$ Nanocrystals for Solar Cell Applications
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Impact of dopant-induced optoelectronic tails on open-circuit voltage in arsenic-doped Cd(Se)Te solar cells
Fluctuations refer to inhomogeneity in the distribution of donors and acceptors at the nanometer scale and occur in many compound solar cell materials such as Cu(In,Ga)Se 2 , Cu 2 ZnSn(S,Se) 4 , and CdSe x Te 1-x . In this work, numerical simulations show that these fluctuations produce not only electrostatic potential variation, but also, local changes in the carrier density and effective bandgap. For a CdSe x Te 1-x absorber doped with arsenic, simulations and cathodoluminescence data within single grains demonstrate how donor and acceptor densities—consistent with capacitance-voltage and secondary-ion mass-spectrometry data—produce tails in photoluminescence, quantum efficiency, and absorption measurements. Using multiple theoretical approaches, we demonstrate that the fluctuations can hinder expected performance gains from increased carrier density, and we describe the significant open-circuit voltage deficit observed in the CdSe x Te 1-x :As solar technology. Our results demonstrate that it is critical to characterize and reduce carrier compensation to realize a higher efficiency.
Mechanisms for long carrier lifetime in Cd(Se)Te double heterostructures
II–VI semiconductors are used in numerous electro-optical applications. For example, CdTe-based solar technology is cost competitive with other electricity generation sources, yet there is still significant room to improve. Carrier lifetime has historically been well below the radiative recombination limit. Lifetimes reaching beyond 100 ns can significantly enhance performance and enable novel device structures. Here, double heterostructures (DHs) with passivated interfaces demonstrate lifetimes exceeding 1 µs, yet this appears only for CdSeTe and not for CdTe DHs. We compare the passivation mechanisms in CdTe and CdSeTe DHs. CdSeTe lifetimes on the order of 1 µs correspond to a combination of superior intragrain lifetime, extremely low grain boundary recombination and greater Te4+ interfacial presence compared to CdTe.