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In this report, ternary semiconducting NixBi2−xS3(x = 0.2 M and 0.5 M) thin films were synthesized in situ for the first time by a chemical bath deposition technique at different bath temperatures (60 °C, 70 °C and 80 °C). The effects of concentration and deposition temperature on the deposited films were studied by combining the results of structural, morphological, optical and electrical analyses. The growth of NixBi2−xS3 films with good crystalline nature and interconnected grain arrangement takes place due to increasing the concentration of Ni2+ ions in bismuth sulfide matrix. EDS result confirmed the stoichiometry of NixBi2−xS3 formation. Wettability test demonstrated that the surface of the film was hydrophilic in nature. The optical absorption spectra revealed that the bandgap Eg of the x = 0.5 M film deposited at 70 °C was about 1.36 eV. Current-voltage (I-V) characteristics of the x = 0.5 M film deposited at 70 °C were studied under X-ray radiation and dark condition. An X-ray detection sensitivity analysis showed that the detection sensitivity is optimum when the bias voltage applied across the film is low (~0.9 V). These findings reveal that the film with x = 0.5 M deposited at 70 °C can be used as an efficient low cost X-ray sensor.

Cu3BiS3 is an absorber material for thin film solar cells with an optimal band gap of 1.10-1.72 eV, high absorption coefficient (>105 cm-1) and abundant constituents. In this paper, the effect of annealing on the properties of chemical bath deposited (CBD) Cu3BiS3 thin films is reported. The annealed Cu3BiS3 thin films were characterized by using the X-ray diffraction (XRD) and Raman spectroscopy. The XRD analysis revealed the formation of polycrystalline Cu3BiS3 thin films with orthorhombic crystal structure at 673K. The average crystallite size as calculated from the Debye-Scherrer’s formula was found to be 22.09 nm for (131) peak. Raman spectra showed a leading peak at 282 cm-1 that is a characteristic of Cu3BiS3.

For widespread application of thin-film photovoltaic solar cells, synthesis of inexpensive absorber material is essential. In this work, deposition of ternary Cu3BiS3 absorber material, which contains abundant and environmentally benign elements, was carried out on glass substrate. Flowerlike Cu3BiS3 thin films with nanoflakes as building block were formed on glass substrate by chemical bath deposition. These films were annealed at 573 K and 673 K in sulfur ambient for structural improvement. Their structure was characterized using Raman spectroscopy, as well as their surface morphological and optical properties. The x-ray diffraction profile of as-deposited Cu3BiS3 thin film revealed amorphous structure, which transformed to orthorhombic phase after annealing. The Raman spectrum exhibited a characteristic peak at 290 cm−1. Scanning electron microscopy of as-deposited Cu3BiS3 film confirmed formation of nanoflowers with diameter of around 1052 nm. Wettability testing of as-deposited Cu3BiS3 thin film demonstrated hydrophobic nature, which became hydrophilic after annealing. The measured ultraviolet–visible (UV–Vis) absorption spectra of the Cu3BiS3 thin films gave an absorption coefficient of 105 cm−1 and direct optical bandgap of about 1.42 eV after annealing treatment. Based on all these results, such Cu3BiS3 material may have potential applications in the photovoltaic field as an absorber layer.

Novel nanofibers of wittichenite Cu3BiS3 thin films were successfully developed by use of a simple and low cost chemical bath deposition method. The Cu3BiS3 thin films were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Raman spectroscopy, surface wettability and optical absorption spectra. The XRD shows a formation of wittichenite Cu3BiS3 pure phase of orthorhombic structure. SEM reveals the formation of a network of nanofibers having a large surface area. Raman study shows a major peak at 284 cm−1 and confirms the formation of pure phase of Cu3BiS3. All thin films of Cu3BiS3 were hydrophilic in nature as contact angle of each film is

Since the last few decades, light-absorbing materials based on CuInGaSe2 (CIGS), CuInS2 (CIS), and CdTe have dominated the research in thin-film solar cells. To fabricate large-scale solar cells from these materials, problems may arise due to limited availability of the constituents, viz. Se, In, Cd, and Te, and the toxicity of some of these elements. Hence, recent research efforts are attentive toward abundantly available non-toxic, larger value of absorption coefficient and non-conventional elements. The Cu3BiS3 having wittichenite orthorhombic structure is one the most promising absorber layer candidates for low-cost thin-film solar cells. It has suitable direct band gap (1.10–1.86 eV), large absorption coefficient (105 cm−1) with composition of earth abundant, and relatively non-toxic and cost-effective constituents. Till now, a majority work was done on the preparation of Cu3BiS3 thin films by various techniques. Therefore, a comprehensive review of recent literature of Cu3BiS3 is urgently required. This paper will review the various techniques that have been used to deposit Cu3BiS3 semiconductor with the hope of new paths for the beginner.

ZnS thin films were grown on glass substrate using successive ionic layer adsorption and reaction (SILAR) technique at room temperature. Aqueous solutions of ZnCl2 and Na2S were used as precursors. The X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Raman spectroscopy and optical absorption measurements were applied to study the structural, surface morphology and optical properties of as-deposited ZnS thin films. The X-ray diffraction profiles revealed that ZnS thin films consist of crystalline grains with cubic phase. Spherical nano grains of random size and well covered on the glass substrate were observed from FESEM. The average grain size were found to be 77 nm, 100 nm and 124 nm for 20 cycles, 40 cycles and 60 cycles samples respectively. For 60 cycle sample, Raman spectra show two prominent peaks at 554 cm−1 and 1094 cm−1. The optical band gap values were found to be 3.76 eV, 3.72 eV and 3.67 eV for 20 cycle, 40 cycle and 60 cycle samples respectively.

First time, copper bismuth sulfide (Cu3BiS3) thin films were synthesized on the glass substrate using simple, low-cost chemical bath deposition (CBD) technique. The synthesized parameters such as temperature of bath, pH and concentration of precursors were optimized for the deposition of uniform, well adherent Cu3BiS3 thin films. The optical, surface morphology and structural properties of the Cu3BiS3 thin films were studied using UV-VIS-NIR spectra, scanning electron microscopy (SEM) and X-ray diffraction (XRD). The as- synthesized Cu3BiS3 film exhibits a direct band gap 1.56 to 1.58 eV having absorption coefficient of the order of 105 cm−1. The XRD declares the amorphous nature of the films. SEM images shows films were composed of close-packed fine spherical nanoparticles of 70-80 nm in diameter. The chemical composition of the film was almost stoichiometric. The optical study indicates that the Cu3BiS3 films can be applied as an absorber layer for thin film solar cells.