Role of π-spacer in Regulating the Photovoltaic Performance of Copper Electrolyte Dye-sensitized Solar Cells Using Triphenylimidazole Dyes

In dye-sensitized solar cells (DSSC), π-spacers play a critical role in regulating photovoltaic accomplishment. This is more pronounced when we use alternate redox mediators like cobalt and copper which are...

Correction: Resurgence of DSCs with copper electrolyte: a detailed investigation of interfacial charge dynamics with cobalt and iodine based electrolytes

Correction for ‘Resurgence of DSCs with copper electrolyte: a detailed investigation of interfacial charge dynamics with cobalt and iodine based electrolytes’ by Sourava C. Pradhan et al., J. Mater. Chem. A, 2018, 6, 22204–22214, DOI: 10.1039/C8TA06948D.

Purification of Industrial Copper Electrolyte from Bismuth Impurity

This work focused on purifying copper electrolytes from a bismuth impurity on a laboratory scale. The electrolyte came from Polish copper electrorefineries with the content of main components, g/dm3: 49.6 Cu, 160 H2SO4. The electrolyte was enriched in bismuth by Bi2O3 addition. Purification of bismuth contamination was carried out using selected agents with adsorbing effects, such as barium hydroxide octahydrate, strontium carbonate, barium carbonate, barium and lead sulfates. The trials were performed until achieving the Bi level—below 0.1 g/dm3. During the experiments, it was noticed that electrolyte purification degree depends on initial Bi concentration in electrolyte, time and temperature, as well as on the type and amount of the bismuth-lowering agent. The most satisfactory results of Bi impurity removal were with additions of barium hydroxide octahydrate, strontium carbonate and barium carbonate to electrolyte at 60 °C for 1 h. These parameters revealed the highest electrolyte purification degree. Bismuth is not removed effectively from electrolytes by barium sulfate or lead sulfate addition. The efficiency of the purification process is much higher when the agents are added to the solution in the form of carbonates or hydroxides. Extending the electrolyte purification process time may cause dissolution of bismuth from the resulting precipitate and increase of bismuth concentration in electrolytes.

Disposal of copper electrofining solutions

The paper presents studies of the processing of spent copper electrolyte from the processing of non-ferrous metal scrap at a copper smelter in Kazakhstan. For the processing of the spent electrolyte, a stage-by-stage neutralization was carried out using zinc sublimates and potash. As a result of the first stage of neutralization with zinc sublimations to pH 4.7, a precipitate with a content of PbO 44.69 %; PO2 16.36 % was obtained. After processing the sediment with an alkaline solution, carbonization and melting at a temperature of 900 oC, metallic lead and tin-containing slag with a content of SnO2 of 16.36 % were obtained. As a result of the second stage of neutralization with potash to pH 7.1, a precipitate was obtained-with a CuO content of 76.45 %. After the third stage of neutralization with potash to pH 9.5, a precipitate with a content of NiO 27.63 % and ZnO 55.75 % was obtained. After treatment of the precipitate with a solution containing 100 g / dm3 KOH, a zinc-containing solution with a ZnO content of 225.0 g/dm3 and a precipitate were obtained, after calcination of which nickel oxide with a NiO content of 89.14 % was obtained.

Removal of Sb Impurities in Copper Electrolyte and Evaluation of as and Fe Species in an Electrorefining Plant

Antimony and arsenic concentrations and their oxidation states (Sb(III), Sb(V), As(III) and As(V)) in copper electrorefining electrolyte can affect copper cathode quality through the formation of floating slimes. A laboratory-scale pilot plant was operated to remove Sb from commercial electrolyte. The pilot plant consisted of a pre-treatment process with copper shavings followed by ion exchange. The results indicated that Sb(III) was removed from copper electrolyte completely, while Sb(V) was partially eliminated. The concentrations of As(III) and As(V) were not affected, and the poisoning of the ion exchange resin by Fe(III) was avoided by pre-reduction to Fe(II) by copper shavings. The operation configuration of the pilot plant was applied to the design of an industrial plant for Sb/Bi removal at the Atlantic Copper Refinery in Huelva, Spain. The evolution of Sb, Fe and As species in the commercial electrolyte was monitored prior to and after the installation of the Sb/Bi removal plant. The results show a ca. 45% decrease in total Sb content (from 0.29 g L−1 to 0.16 g L−1) in the electrolyte. This reduction is more noticeable for Sb(III), whose concentration decreased from 0.18 g L−1 to 0.09 g L−1, whereas Sb(V) concentration diminished from 0.11 g L−1 to 0.07 g L−1. The resin also retained ca. 75% of the Bi content (0.15–0.22 g L−1). The total As increased during the study period (from 7.7 to 9.0 g L−1) due to changes in plant inputs. Arsenic was predominantly As(V) (ca. 93–95%). The total Fe concentration experienced little variation (0.9–1.1 g L−1) with Fe(II) being the main species (ca. 94–96%).

Effect of Cd2+ on Electrodeposition of Copper in Cyclone Electrodeposition

A strategy to determine the effect of Cd2+ on the electrodeposition of copper from a copper electrolyte by cyclone electrowinning is presented. The concentration of Cu2+ in the copper electrolyte with different Cd2+ concentrations was determined by atomic absorption spectrometry (AAS). It indicated that the current efficiency, the rate of electrodeposition, and the rate copper electrodeposition decreased with the addition of Cd2+ in the three stages of electrodeposition. The current efficiency declined from 99.6 to 79.2% and the copper electrodeposition rate declined from 52 to 40% in the first electrodeposition. The current efficiency had no significant change, and the copper electrodeposition rate declined from 88 to 77% in the second electrodeposition. The current efficiency declined from 72.6 to 40.3%, and the copper electrodeposition rate was all at 99% in the third electrodeposition. The influences of the Cd2+ concentration on the purity and morphology of cathode copper were investigated. The effect of Cd2+ concentration on the purity and morphology of cathode copper was also studied. In the three-stage electrodeposition, the addition of the Cd2+ concentration mainly affected the microstructure of the cathode copper, but it had little effect on the purity of the cathode copper. The higher the amount of Cd2+, the rougher the morphology of the cathode copper and the larger the gap between the grains; the higher the amount of Cd2+, the lower the electrodeposition rate and current efficiency, though the reduction was small.

Investigation on the Origin of Variation in Photovoltaic Performance Using D-D-π-A and D-A-π-A Triphenylimidazole Dyes with Copper Electrolyte

The potential of using non-planar triphenylimidazole donor-based dyes in dye-sensitized solar cells was explored by synthesizing two novel dyes LG-P1 and LG-P3, in D-D-π-A and D-A-π-A architectures. Anthracene and benzothiadiazole...