CdS Materials Research Articles

De-Implementing Opioid Use and Implementing Optimal Pain Management Following Dental Extractions (DIODE): Protocol for a Cluster Randomized Trial.

BackgroundOverdose deaths from prescription opioid analgesics are a continuing crisis in the United States. Opioid analgesics are among the most frequently prescribed drugs by dentists. An estimated 5 million people undergo third-molar extractions in the United States each year, resulting in postoperative pain. Studies show that, in most cases, the combination of ibuprofen and acetaminophen is an effective alternative to commonly prescribed opioid analgesics for the management of postextraction pain. Nevertheless, many dentists routinely prescribe opioids after dental extractions.ObjectiveWe describe the rationale, design, and methods for a randomized trial of interventions designed to de-implement opioid prescribing by dentists while implementing effective nonopioid analgesics following dental extractions.MethodsUsing a prospective, 3-arm, cluster randomized trial design with dentists as the unit randomized and patient-level prescribing data as the primary outcome, we will compare different strategies to reduce the reliance on opioids and increase the use of alternative pain management approaches utilizing information support tools aimed at both providers and their patients. The study will test the efficacy of 2 interventions to decrease opioid prescribing following dental extractions: clinical decision support with (CDS-E) and without patient education (CDS). Providers will be randomized to CDS, CDS-E, or standard practice. Patient-level outcomes will be determined via review of comprehensive electronic health records. We will compare study arms on differential change in prescribing patterns from pre- to postimplementation of the intervention. The primary outcome of interest is a binary indicator of whether or not the patient received an opioid prescription on the day of the extraction encounter. We will also examine recommendations or prescriptions for nonopioid analgesics, patients’ perceptions of shared decision making, and patients’ pain experiences following the extraction.ResultsThe HealthPartners Institutional Review Board approved the study. All study materials including the CDS and patient education materials have been developed and pilot tested, and the protocol has been approved by the National Institute of Dental and Craniofacial Research. The intervention was implemented in February 2020, with 51 dentists who were randomized to 1 of the 3 arms.ConclusionsIf the intervention strategies are shown to be effective, they could be implemented more broadly in dental settings with high levels of opioid prescribing.Trial RegistrationClinicalTrials.gov NCT03584789, https://clinicaltrials.gov/ct2/show/NCT03584789International Registered Report Identifier (IRRID)DERR1-10.2196/24342

DFT study of the structural and optoelectronic properties of Cd[formula omitted]Ag[formula omitted]S half metallic alloys

In this work, we report a theoretical investigation of the structural, electronic and optical properties of Cd1−xAgxS alloys with a wurtzite structure. The calculations were performed using the density functional theory (DFT). The full potential linearized augmented plane wave (FPLAPW) scheme, implemented in Wien2k package, was employed. The modified Becke–Johnson potential with generalized gradient approximation (mBJGGA), which combines the Becke–Johnson exchange potential with the generalized gradient approximation correlation potential, was used to evaluate the alloys band structure. The study was carried out for the composition of silver x=0, 0.027, and 0.055. The obtained band structures and the density of states of these alloys revel that by increasing the silver composition in CdS matrix, the Fermi level cross the E(k) curves in the majority-spin states showing a metallic behavior. While the minority-spin state is semiconducting. A band gap channel was observed between the spin up and spin down level giving rise to a half metallic behavior. The origin of this bandgap is attributed to the silver d-band hybridization. The optical properties were also investigated and were found to be deeply affected by the silver composition. The optical absorption is gradually shifted to the lower energy and the compound becomes more absorbent in the infrared region. The structural and optoelectronic proprieties of the half metal Ag-doped CdS materials, were investigated and are presented in the current study and discussed in details. The findings of the study show that Cd1−xAgxS alloys with their spin-based properties could pave the way for many novel optoelectronic devices in addition to spintronics applications.

Investigation on spectroscopic and electrical properties of p-Si/CdSxSe1−x (0≤ x ≤1) heterostructures for photodetector applications

CdSxSe1−x (0 ≤ x ≤ 1) films were deposited on p-Si via thermal co-evaporation method with CdS and CdSe as source materials. The heterostructures were studied for their structural, spectroscopic and electrical be�haviours by using X-ray diffraction, photoluminescence spectroscopy, low temperature Raman spectroscopy and I-V characterization. Systematic shift in the diffraction peak has confirmed the composition modulation and presence of mixed phase in the ternary CdSSe. Temperature dependent Raman study showed that longitudinal optical modes are shifted to higher wavenumber, which is ascribed to variation in strain and lattice constants with temperature. The diode parameters including ideality factor and barrier height were extracted by applying various models to the temperature dependent I-V measurements. The spectral re�sponse of p-Si/CdSxSe1−x (0 ≤ x ≤ 1) were analysed and the heterostructure with x = 0.2 showed high response confirming the device suitability of the heterostructures

Synthesis of Immobilized CdS/TiO2 Nanofiber Heterostructure Photocatalyst for Efficient Degradation of Toluene

The immobilized CdS/TiO2 nanofiber (CdS/TiO2 NF) heterostructure photocatalyst was fabricated via anodic oxidation and cyclic impregnation method. The microstructure of CdS/TiO2 NF was characterized by SEM and TEM. The components of CdS/TiO2 NF were identified by EDX, XPS, and Raman. The optical properties of CdS/TiO2 NF were characterized by UV-vis DRS and PL. Results showed that CdS was loaded on the surface of TiO2 NF in the form of particles with a diameter of about 10–80 nm. The Cd and S elements were detected on the surface of catalyst. CdS/TiO2 NF improved the absorption performance in the ultraviolet and visible light regions and reduced the recombination of photogenerated electron-hole pairs. The performance of CdS/TiO2 NF on degrading toluene was investigated. Results showed that the deposition of CdS enhanced the photocatalytic activity of TiO2 NF. The toluene concentration, catalyst dosage, and flow rate had marked impact on the photocatalytic degradation efficiency of toluene. In this reaction system, the degradation ratio was 80.71% when the toluene concentration was 13 mg·L−1, the photocatalyst area was 32 cm2, the flow rate was 3 L·min−1, and the illumination time was 100 min. The mineralization ratio after photocatalytic reaction for 100 min was about 45.02%. The immobilized CdS/TiO2 NF photocatalyst is easy to be recycled, which can reduce the energy and material cost. This work not only highlights the intrinsical role of CdS materials in the enhanced photocatalytic performance of TiO2 NF but also provides significant guidance on fabricating immobilized CdS/TiO2 NF photocatalyst applied in environment remediation.

Cd-free Cu(InGa)Se2 solar cells with eco-friendly a-Si buffer layers

CdS, In2S3 and ZnO-based materials are typically adopted as buffer layers in high efficiency CIGS solar cells. However, the drawbacks involved toxicity, complicated synthesis process and environmental damage of aforementioned materials would someday limit the development themselves. Here, for the first time, eco-friendly and low-cost a-Si thin films prepared by e-beam evaporation were used as buffer layers in CIGS solar cells. Thickness of a-Si films was changed to optimize the performance of CIGS solar cells through investigating their optical, structural and electrical properties. It revealed that the conduction band alignment of CIGS and a-Si is a favorable spike and a 60 nm a-Si film is optimal for CIGS/a-Si interface properties. Following the SCAPS simulation, bandgaps and conduction band energy level of CIGS films were facilely modulated through altering the Ga/(Ga + In) ratios. The conversion efficiency of solar cell with modified CIGS film was relatively improved by over 30% compared to the pristine one. The present work provides a new and eco-friendly strategy for fabrication of CIGS solar cells and expands the application of a-Si thin films as buffer layers for solar cells.

Compositional variation dependent colour tuning and observation of Förster resonant energy transfer in Cd(1−x)ZnxS nanomaterials

Energy level diagram of FRET process in Cd(1−x)ZnxS nanomaterials between donor (ZnS) and acceptor (CdS): the smaller ZnS materials transfer energy nonradiatively to the larger CdS materials when there is sufficient spectral overlap between them.

The electronic and optical properties of an exciton, biexciton and charged excitons in CdSe/CdTe-based multi-shell type-II quantum dot nanocrystals

It has been recently reported that multi-shell type-II quantum dot nanocrystals (QDNCs) have higher quantum yields. Besides these higher quantum yields of multi-shell type-II QDNCs, additional second layer has been a critical influence on the formation mechanisms of the excitonic structures. Understanding of bound and unbound cases of the excitonic structures in multi-shell type-II QDNCs gives some important information for applications. In this study, we have investigated the electronic and optical properties of a single exciton (X), biexciton (XX), and positively and negatively charged excitons ( $${\mathsf {X^+}}$$ and $${\mathsf {X^-}}$$ ) in CdSe/CdTe-based multi-shell type-II QDNCs. In the study, three different structure compositions, i.e., CdSe/CdTe, CdSe/CdTe/CdS, and CdSe/CdTe/ZnTe, have been considered. We have observed that CdS and ZnTe materials have drastically changed the electronic and optical properties of the bare CdSe/CdTe type-II QDNCs.

CdZnS solid solution supported Ce2Sn2O7 pyrochlore photocatalyst that proves to be an efficient candidate towards the removal of organic pollutants

Novel Ce2Sn2O7/CdZnS nanostructure has been constructed successfully by the hydrothermal methods. The CdZnS solid solution act as an excellent supporting material to the pyrochlore Ce2Sn2O7 nanorods. Several characterization techniques have been applied to explore the phase structure, elemental composition, optical properties and photoinduced catalytic activity. The photocatalytic activity of the Ce2Sn2O7 rod/ CdZnS solid solution and pure Ce2Sn2O7, CdZnS and CdS materials were investigated under visible light and direct solar irradiation with ambient environment. The obtained Ce2Sn2O7/CdZnS nano composite possess increased photocatalytic activity for the degradation of Rh B as well as various organic pollutants. Moreover, the Ce2Sn2O7/CdZnS shows the good photocatalytic efficiency for the colorless organic pollutants. The increased photocatalytic activity of the Ce2Sn2O7/CdZnS is due to the close contact between the Ce2Sn2O7 and CdZnS nanomaterials. To confirm the role of the reactive species in the photocatalytic reaction, the trapping experiments have been conducted and the results are discussed with the detailed information.

A heterojunction bipolar transistor architecture-based solar cell using CBTSSe/CdS/ACZTSe materials

We propose a heterojunction bipolar transistor (HBT) architecture for solar cell using earth-abundant CBTSSe, CdS and ACZTSe materials. The proposed CBTSSe/CdS/ACZTSe structure has a pnp transistor architecture where high band gaps CBTSSe/CdS form the emitter/base junction and ACZTSe acts as low bandgap collector. Using optoelectronic simulations, we investigate the performance of the proposed solar cell and optimize different layer thicknesses to maximize its efficiency. The optimized efficiency of the designed solar cell is found to be 21.63% with 735 mV open circuit voltage, 38.39 mAcm−2 short circuit current and 76.7% fill factor including Shockley–Read–Hall (SRH), surface and radiative recombination mechanisms. The optimized thicknesses of CBTSSe, CdS and ACZTSe layers are calculated to be 300 nm, 50 nm and 800 nm, respectively. The significance of this HBT solar cell lies in its simplicity of the structure that doesn't require tunneling junction and reduces the number of layers to achieve efficiency comparable to dual junction kesterite solar cells. The design and analysis presented in this article would help in achieving highly efficient inorganic solar cells at low cost and less fabrication complexities.

Effect of cadmium precursor on the physico-chemical properties of electrochemically-grown CdS thin films for optoelectronic devices application: a comparative study

Thin film CdS materials for possible optoelectronic devices application have been synthesized by the electrochemical deposition method, using two different cadmium salts and sodium thiosulphate as precursors. In order to keep the synthesis process as simple as possible, no additional chemicals were added as complexing agents or buffers, and a two-electrode set-up was used. The qualities of the resulting films from the different cadmium precursors were compared by characterizing them for their physico-chemical properties using state-of-the-art glancing incidence X-ray diffraction, UV–Vis spectrophotometry, scanning electron microscopy and energy dispersive X-ray spectroscopy (EDX). The results obtained show significant influence of cadmium precursor on the structural, optical and chemical properties of the films. Whereas CdCl2 precursor produced CdS with purely hexagonal structure in both as-grown and heat-treated conditions, Cd(CH3COO)2 produced CdS with purely cubic crystal structure, with films from both precursors showing clear difference in physical appearance. Energy bandgap values estimated for the films are in the range (2.49–2.57) eV and (2.22–2.23) eV in as-deposited form, with CdCl2 and Cd(CH3COO)2 precursors respectively. After annealing, these values become 2.42 eV with CdCl2 and (2.30–2.31) eV with Cd(CH3COO)2. Although CdS from both precursors show similar surface morphology, EDX results reveal that CdS films from CdCl2 precursor are more stoichiometric with Cd/S atomic ratios of (0.90–0.93) compared to films from Cd(CH3COO)2 precursor with Cd/S values of (0.87–0.88).

Matrix Calculation of the Spectral Characteristics of AII–BVI Semiconductors Doped with Iron-Group Ions

A method for the matrix calculation of the spectral characteristics of AII–BVI semiconductors doped with iron-group ions is proposed, which takes into account all possible interactions in the ion and the effect of intramolecular surrounding fields of different symmetries. A technique for calculating the oscillator strength on the basis of eigenfunctions of the resulting states of 3d7, 3d8, and 3d6 electron configurations is developed. The spectral regularities of the Co2+, Ni2+, and Fe2+ energy structures for the ZnO, ZnS, ZnSe, ZnTe, CdO, CdS, CdSe, and CdTe materials are studied. All possible spectral bands in iron-group ions implanted in AII–BVI semiconductors in the range of 1.3–3 μm are established. The possibility of implementing the laser effect on these materials is estimated.

Influence of the type of conducting glass substrate on the properties of electrodeposited CdS and CdTe thin films

Owing to the greater efficiency in energy conversion by absorbing energy in a wider range of the solar spectrum, thin film CdS/CdTe solar cells have been popularized as a prominent application of photovoltaics and the technique of electrodeposition (ED) is an ideal method available for producing both CdS and CdTe materials upon its outrivaled simplicity, low cost, scalability and manufacturability. Typically the quality of these deposited thin films depends on several growth parameters and amid them, the type of conducting glass substrate plays a crucial role. This study is focused on the influence of conducting glass substrate on the properties of electrodeposited CdS and CdTe thin films. Two types of glass substrates coated with different transparent conducting oxide (TCO) layers namely; fluorine-doped tin oxide (FTO) and indium tin oxide (ITO) having different sheet resistances (FTO: 7 and 13 Ω/sq and ITO: 7 and 15 Ω/sq) were considered. CdS and CdTe materials were electrodeposited respectively on each of these types of TCO layers using a three electrode electrolytic system under a consistent set of growth parameters which has been pre-optimized with respect to FTO having sheet resistance of 7 Ω/sq. The deposited CdS and CdTe thin layers were subsequently heat treated and characterized to understand their optical, electrical, morphological and structural properties. Accordingly, CdS and CdTe semiconductor materials deposited on glass/FTO (7 Ω/sq) substrates have exhibited better optoelectronic qualities and hence, endorse the requirement of individual growth parameter optimization for each type of TCO glass substrate for the production of good quality CdS and CdTe thin films in photovoltaic device fabrications.

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AbstractA method for the matrix calculation of the spectral characteristics of AII–BVI semiconductors doped with iron-group ions is proposed, which takes into account all possible interactions in the ion and the effect of intramolecular surrounding fields of different symmetries. A technique for calculating the oscillator strength on the basis of eigenfunctions of the resulting states of 3 d ^7, 3 d ^8, and 3 d ^6 electron configurations is developed. The spectral regularities of the Co^2+, Ni^2+, and Fe^2+ energy structures for the ZnO, ZnS, ZnSe, ZnTe, CdO, CdS, CdSe, and CdTe materials are studied. All possible spectral bands in iron-group ions implanted in AII–BVI semiconductors in the range of 1.3–3 μm are established. The possibility of implementing the laser effect on these materials is estimated.

RETRACTED: Morphological, optical and structural analysis in CdS, CdS-CdCO3 and CdCO3 thin solid films grown by chemical bath

Abstract CdS, CdS-CdCO3 and CdCO3 thin films grown by chemical bath at ∼80, ∼60 and ∼40 °C temperature range were prepared. Morphology and size showed changes as a variety of truncated cube-shaped structures, wires and circles. Energy band gap was ∼2.4 eV (CdS) and ∼4.0 eV (CdCO3), respectively. XRD showed wurtzite crystalline phase for CdS films and a rhombohedral phase for CdCO3. Raman spectra in CdS exhibited a peak for A1(TO) phonon corresponding to wurzite and CdCO3 film showed internal vibrations of C O 3 2 − group: v1-symmetric stretching (∼1090 cm−1) v3-asymmetric C O stretching (∼1401 cm−1); v4-in-plane band of the C O 3 2 − ions and two bands assigned to translations and release of the C O 3 2 − group relative to the Cd atoms: v13 (∼274 cm−1), v14 (∼169 cm−1). Lattice modes v13 (∼274 cm−1), v3- asymmetric C O stretching (∼1401 cm−1), v1-symmetric C O stretching ∼1090 cm−1 were also noted. Finally, a simple thermodynamic analysis is presented to understand the formation of the compounds by calculations of Gibbs free energy and data associated with the corresponding ions of the CdS and CdCO3 materials in our working conditions.

Visible-light-driven photocatalytic system based on a nickel complex over CdS materials for hydrogen production from water

Based on that the evolution of renewable H2 by using a photochemical method requires photoinduced electron transfer (ET) from a light harvester to an electrocatalyst in water, we present a nickel complex, [BzPyN(CH3)2]2[Ni(i-mnt)2] 1 (i-mnt2−=2,2-dicyanoethylene-1,1-dithiolate) that acts as both an electrocatalyst and a photocatalyst for H2 generation from water via an unstable nickel hydride intermediate. As an electrocatalyst, this nickel complex can catalyze hydrogen generation from a neutral buffer with a turnover frequency (TOF) of 577.4mol of hydrogen per mole of catalyst per hour (mol H2/mol catalyst/h) at an overpotential (OP) of 837.6mV. As a photocatalyst, combining with CdS nanorods (CdS NRs) as a photosensitizer, and ascorbic acid (H2A) as a sacrificial electron donor, it can photocatalyze hydrogen evolution in heterogeneous environments and can work for 100h. Under an optimal condition, the highest hydrogen evolution turnover number (TON) reaches 85820mol of H2 per mol of catalyst during 70h irradiation, and the highest apparent quantum yield (AQY) is ∼23% at 420nm. And possible cycles for H2 production by the electrocatalytic and photocatalytic systems are afforded.

Single CdS Nanorod for High Responsivity UV–Visible Photodetector

1D nanoscale photodetectors have been extensively investigated for the unique geometry structure and novel physical and chemical properties. The 1D CdS materials have received much attention in the field due to its high photosensitivity and fast response, while how to achieve high responsivity is still in development, despite it is the crucial target to the excellent photodetector. Single crystal CdS nanorods (NRs) are synthesized on SiO2/Si substrate over large scale via the chemical vapor deposition method. The individual single CdS nanorod photodetector have been fabricated by using photolithography process and the responsivity of the photodetector is investigated systematically. At a very low percentage of illumination intensity (2%, 0.5 mW cm−2) under 450 nm, the photodetector exhibited a high responsivity and reached at 1.23 × 104 A W−1 with the bias voltages of 2 V. The good crystallinity and large surface of CdS nanorod are the reasons of this excellent performance of CdS based photodetector. The strategy proposed herein appears to hold great potential for a high responsivity with low illumination intensity.

Structural, morphological, optical and hologram recording of the CdS and ZnS thin films by double exposure digital holographic interferometry technique

In this paper, we have used double exposure digital holographic interferometry (DEDHI) technique for hologram recording of electrochemical synthesis of the CdS and ZnS thin films materials. As synthesis CdS and ZnS thin films are characterized by different characterization techniques such as X-ray diffraction (XRD), Field emission scanning electron microscopy (FE-SEM), optical band gap, and contact angle measurement. Further recording of the holograms has been carried out with different deposition time of CdS and ZnS thin films, and we have used mathematical relation between stress, mass deposited thickness of thin film and fringe width. It is seen that the fringe width, mas of deposited samples, stress to substrate changes with the time of deposition.

Effects of Aliovalent Anion Substitution on the Electronic Structures and Properties of ZnO and CdS

AbstractAliovalent anion substitution in ZnO, CdS, and related materials brings about drastic changes in their electronic structure and properties, making them colored, with a narrow band gap. Progressive substitution of N and F in ZnO leads to the formation of Zn2NF, with complete replacement of O with N and F. The band gaps of Zn2NF and O‐doped Zn2NF are smaller than the band gap in ZnO, because N 2p states create a new sub‐band above the valence band. Band‐edge energies of these compounds are thermodynamically favorable for water splitting. First‐principles calculations of P‐ and Cl‐substituted CdS and ZnS show the presence of a band just above the valence band, due to the p orbitals of the trivalent dopant, resulting in a noticeable reduction in the band gap of these materials. Such substitution of anions can be quite effective in engineering the valence band, and hence, in tuning the related properties of materials. Complete substitution of S with P and Cl in CdS should result Cd2PCl, but the resulting material is Cd2PCl1.5 or Cd4P2Cl3. Cd4P2Cl3 shows a band gap of 2.36 eV and a photoluminescence band at 580 nm. First‐principles calculations show it to be an effective photocatalyst for water splitting; it is shown experimentally to exhibit photocatalytic hydrogen evolution in the presence and absence of a sacrificial agent. Moreover, resilience to photocorrosion is a unique property of Cd4P2Cl3.

CdS bulk crystal growth by optical floating zone method: strong photoluminescence upconversion and minimum trapped state emission

CdS materials have shown promise in optical refrigeration. However, the current success of laser cooling is still limited to nanobelt morphology. It is, therefore, important to explore whether bulk crystal growth technology could provide high-quality materials for laser cooling studies. Herein, we have demonstrated CdS bulk crystal growth by a modified optical floating zone method. The low temperature and continuous displacement of the CdS crystalline zone have resulted in high-quality CdS bulk crystals, which show strong photoluminescence upconversion with the absence of the long-wavelength and broad emission centered ∼700 nm that commercial CdS wafers usually exhibit. All these characterizations have confirmed the excellent stoichiometric nature and crystal quality of CdS bulk crystals, which is much better than the commercial counterparts for laser cooling studies.

Development of a novel electrochemical DNA biosensor based on elongated hexagonal-pyramid CdS and poly-isonicotinic acid composite film

Three CdS materials with different shapes (i.e., irregular, rod-like, and elongated hexagonal-pyramid) were hydrothermally synthesized through controlling the molar ratio of Cd2+ to thiourea. Electrochemical experiments showed that the elongated hexagonal-pyramid CdS (eh-CdS) modified on glassy carbon electrode (GCE) had the higher electrical conductivity than the other two forms. Then the eh-CdS modified GCE was further modified with a layer of poly-isonicotinic acid (PIA) through electro-polymerization in IA solution to enhance the stability and functionality of the interface. The layer-by-layer modification process was characterized by atomic force microscopy and electrochemistry. Then 5′-amino functionalized DNA was immobilized on the electrode surface through coupling with the carboxylic groups derived from PIA-eh-CdS composite film. The hybridization performance of the developed biosensor was evaluated using methylene blue as redox indicator, and the results showed that the peak currents of methylene blue varied with target concentrations in a wide linear range from 1.0×10−14M to 1.0×10−9M with a low detection limit of 3.9×10−15M. The biosensor also showed high stability and good discrimination ability to the one-base, three-base mismatched and non-complementary sequence.