Copper Indium di-Selenium, CuInSe2 (CISe) is the most promising absorber material for thin-film solar cells. CISe based solar cells have shown long-term stability and the highest conversion efficiencies of all thin-film solar cells, above 19%. Moreover, CISe based solar cells are very stable and thus their operational lifetimes are long. The deposition method generally has a large impact on the resulting film properties as well as on the production costs. CISe can be prepared by a variety of methods like physical and chemical methods. The present review discusses first the liquid phase synthesis method like chemical bath deposition (CBD), electro-deposition (ED), spray pyrolysis (SP), and successive ionic layer adsorption and reaction method (SILAR), etc. Next, the structural, optical, electrical, and photo-electrochemical properties of CISe, as well as features of solar cells made thereof are reviewed. The last part of the text deals with the application of CISe thin-film absorbers in solar cells. The photo-response properties of the CISe are discussed how they can improve the efficiency and reduce the cost in potential applications.

No abstract

No abstract

No abstract

No abstract

In the present paper, the influence of precursor concentration on the structural, optical, and humidity sensing properties of spray-deposited titanium dioxide (TiO2) films are investigated. The TiO2 thin films were successfully deposited by spraying different precursor concentrations such as 0.075 M, 0.1 M, and 0.125 M of titanium trichloride solution onto glass substrates. X-ray diffractometry (XRD) studies confirmed the polycrystalline anatase phase of TiO2 with dominant (101) plane. The crystallite size was found to increase with the increase in precursor concentration. The micro-strain and dislocation density in the film was observed to decrease as the crystallite size increased. The UV–vis spectra confirmed the optical absorbance edge of the samples shifted toward lower wavelengths with increased precursor concentration. The humidity sensing properties of the synthesized material were measured by monitoring the change in resistance of the sample with the change in relative humidity. The material synthesized with 0.1 M precursor concentration, by using the spray pyrolysis method, shows good sensitivity and has a response time of 77.5 s and fast recovery time of 3 s.

No abstract

Copper selenide (Cu3Se2) thin films have been synthesized with Se as the precursor in aqueous solution by chemical bath deposition technique at room temperature. We have investigated the influence of the growth time ranging from 30 to 90 min on structural, optical and electrical properties of Cu3Se2 thin films. The as-grown film at 60 min exhibits a tetragonal structure and is (101) oriented. The maximum value of crystal size D = 55 nm is attained for Cu3Se2 films grown at 60 min. The Raman spectrum reveals a pronounced peak at 259 cm−1, which is assigned to vibrational (stretching) modes from the covalent Se–Se bonds. The optical band gap energy is 1.91 to 2.01 eV with growth time increased from 30 to 90 min. The scanning electron microscopy (SEM) study reveals that the grains are uniform and spread over the entire surface of the substrate of the film at 60 min. The Hall effect study reveals that the film exhibits p-type conductivity. The synthesized film showed good absorbance in the visible region which signifies that synthesized Cu3Se2 films can be suitable as a sensitized material in semiconductor sensitized solar cells.