A short review on heterojunction photocatalysts: Carrier transfer behavior and photocatalytic mechanisms

Design and synthesis of robust Z-scheme ZnS-SnS2 n-n heterojunctions for highly efficient degradation of pharmaceutical pollutants: Performance, valence/conduction band offset photocatalytic mechanisms and toxicity evaluation.

Structural, optical, and photocatalytic properties of the spray deposited nanoporous CdS thin films; influence of copper doping, annealing, and deposition parameters

Synthesis of CdO nanopowders by a simple soft chemical method and evaluation of their antimicrobial activities

Highly crystalline cadmium doped lead sulphide (PbS:Cd) thin films with different Cd doping concentrations (0, 2, 4, 6 and 8 at-%) were fabricated on glass substrates using spray pyrolysis technique. The X-ray diffraction (XRD) studies revealed that all the films exhibit face centred cubic structure with a preferential orientation along the (2 0 0) plane irrespective of Cd doping concentration. Optical studies showed that the band gap of doped films vary between 1·96 and 2·12 eV with increasing Cd content and the film coated with 6 at-% Cd dopant has a maximum transmittance of nearly equal to 77%. Electrical studies revealed that the film coated with 6 at-%Cd dopant has a maximum conductivity of 12·67×10−1 Ω cm−1. The obtained results infer that the PbS:Cd film coated with 6 at-%Cd dopant has better structural, morphological, optical and electrical properties.

Properties of Cd doped PbS thin films: doping concentration effect

Characteristic analysis on the physical properties of nanostructured Mg-doped CdO thin films—Doping concentration effect

Abstract Thin films of manganese-doped cadmium oxide (CdO:Mn) with different Mn-doping levels (0, 1, 2, 3 and 4 at.%) were deposited on glass substrates by employing an inexpensive, simplified spray technique using a perfume atomizer at 375 °C. The influence of Mn incorporation on the structural, morphological, optical and electrical properties of CdO films has been studied. All the films exhibit cubic crystal structure with a (1 1 1) preferential orientation. Mn-doping causes a slight shift of the (1 1 1) diffraction peak towards higher angle. The crystallite size of the films is found to decrease from 34.63 nm to 17.68 nm with an increase in Mn doping concentration. The CdO:Mn film coated with 1 at.% Mn exhibit a high transparency of nearly 90 % which decreases for higher doping concentration. The optical band gap decreases with an increase in Mn doping concentration. All the films have electrical resistivity of the order of 10−4 Ω·cm.

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Effect of doping concentration on the structural, morphological, optical and electrical properties of Mn-doped CdO thin films

Thin films of lead oxide were synthesized by cost effective spray pyrolysis technique at different substrate temperatures on glass substrates. Effect of substrate temperature on the growth mechanism and physical properties of the films was investigated. All the films were polycrystalline in nature with tetragonal structure corresponding to α-PbO. The films coated at 225 °C and 275 °C were (1 0 1) oriented, while the films deposited at 325 °C and 375 °C were (0 0 2) oriented. Above 375 °C, the pure tetragonal nature deteriorated and the peaks corresponding to orthorhombic phase were observed. The band gap value was found to be in the range of 2.3 to 2.62 eV. All the films had a resistivity of the order of 103 ohm-cm. A minimum resistivity of 0.0191 × 103 ohm-cm was obtained for the film coated at 325 °C. The activation energy increased with increase in substrate temperature.

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Role of substrate temperature on the growth mechanism and physical properties of spray deposited lead oxide thin films

Undoped CdO film and CdO films which are alloyed with Zn and Mg (ZMCO) at different concentrations were prepared by spray pyrolysis technique using perfume atomizer on glass substrates kept at 400 °C. The effect of Zn, Mg incorporation on the structural, morphological, optical and electrical properties of the CdO films were investigated using X-ray diffraction (XRD), scanning electron microscopy, UV–Vis spectroscopy and dc electrical measurements respectively. XRD analysis showed that all the alloyed films exhibit polycrystalline nature having cubic crystal structure with a (1 1 1) preferential orientation similar to that of the undoped sample. All the Zn, Mg incorporated CdO films have good transparency in the visible region. Optical band gap is blue shifted with increasing Zn, Mg concentration. Electrical studies showed that the ZMCO film coated with 6 at.% Zn, Mg concentration exhibit a minimum resistivity of 0.724 × 10−4 Ω-cm. The high transparency, widened band gap energy and improved electrical properties obtained infer that ZMCO thin films find applications in optoelectronic devices, especially in solar cells.

Properties of spray deposited Zn, Mg incorporated CdO thin films

CdS thin films simultaneously doped with Mg and Cl at different doping concentrations (0, 2, 4, 6 and 8 at%) were prepared on glass substrates by spray pyrolysis technique using perfume atomizer at 400 °C. The effect of Mg and Cl doping concentration on the structural, morphological, optical and electrical properties of the deposited films were investigated using X-ray diffraction (XRD), scanning electron microscopy, UV–Vis spectroscopy and dc electrical measurements, respectively. XRD analysis showed that the undoped and doped CdS films exhibit hexagonal structure with a preferential orientation along the (0 0 2) plane. The 2θ angle position of the (0 0 2) peak of the doped films was shifted towards a higher angle with increasing Mg and Cl concentration. The UV–Vis–NIR absorption spectra of Mg and Cl doped thin films are measured and classical Tauc approach was employed to estimate their band gap energies. The increase in band gap energy from 2.46 to 2.73 eV with the reduction in crystallite size supports quantum size effect. Raman spectra implied that more defects existed in the doped samples. Electrical studies showed that all the films have resistivity in the order of 101 Ω-cm and the CdS film with 6 at% Mg and Cl concentration has a minimum resistivity of 1.332 × 101 Ω-cm.

K. Usharani

Papers

Characteristic analysis on the physical properties of nanostructured Mg-doped CdO thin films—Doping concentration effect

Effect of doping concentration on the structural, morphological, optical and electrical properties of Mn-doped CdO thin films

Role of substrate temperature on the growth mechanism and physical properties of spray deposited lead oxide thin films

Properties of spray deposited Zn, Mg incorporated CdO thin films

Structural, morphological, optical and electrical properties of CdS thin films simultaneously doped with magnesium and chlorine