In this research, an azobenzenecarboxylic acid was used as a sufficient co-adsorbent in combination with N719 dye. As it is found from the results, an optimized concentration of the co-absorbent leads to the highest efficiency. The dye-sensitized solar cells (DSSCs) parameters such as short-circuit current (Jsc), open-circuit voltage (Voc) and conversion efficiency (η) were obtained -14.87 mA/cm 2 , 0.765 V and 5.20% respectively. Based on the results, the N719/Azobenzenecarboxylic-based system shows a significant increase in Voc and Jsc, resulting in an ∼21% improvement in the efficiency. A higher conversion efficiency for the co-adsorbent-based systems was assigned to their enhanced η, which is attributed to reduced dye aggregation, higher electron injection and increased Voc. This corresponded to the improved electron density in the TiO 2 conduction band of the photoanode and reduced charge recombination revealed through electrochemical impedance spectroscopy measurements. Also, evidence was provided for a long charge life time and a high resistance of charge recombination for the co-absorbed solar cells.

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Summary In this research, to optimize the surface of the photoanode, two different types of surface coatings were used and their effects on the photovoltaic parameters were investigated. Also, to compare the two different electrolytic systems based on liquid and gel‐state electrolyte, the novel magnetic core‐shell nanocellulose/titanium chloride (Fe3O4@)NCs/TiCl) nanocomposite was introduced into a polymeric system as a nanofiller to decrease the crystallinity of the polymer and enhance the diffusion of triiodide ions in quasisolid‐state dye‐sensitized solar cells (QS‐DSSCs). For this purpose, Fe3O4@)NCs/TiCl was synthesized by coprecipitation of Fe3+ and Fe2+ ions in the presence of nanocellulose and then used as magnetic support for bonding TiCl4 to prepare QS‐DSSCs. Containing a 10.0 wt% magnetic nanocomposite, it displayed a higher apparent diffusion coefficient (Dapp) for I3− ions (4.10 × 10−6 cm2/s) than the gel polymeric electrolyte (GPE) did (1.35 × 10−6 cm2/s). GPEs were characterized using various techniques including current density‐voltage curves, AC impedance measurements, and linear sweep voltammetry (LSV). The photovoltaic values for the short‐circuit current density (Jsc), open‐circuit voltage (VOC), and fill factor (FF) and the energy conversion efficiency (η) of the novel Fe3O4@NCs/TiCl nanocomposite–based QS‐DSSCs were 14.90 mA cm−2, 0.757 V, 64%, and 7.22%, respectively.

A modified carbon paste electrode with 2,2 0 -(1,3-propanediylbisnitriloethylidine)bis-hydroquinone (PBNBH) and TiO 2 nanoparticles has been fabricated and used to study the catalytic oxidation of dopamine (DA), uric acid (UA) and tryptophan (Trp). The overpotential of DA reduced about 0.36 V. Based on its strong catalytic function toward the oxidation of DA, UA and Trp, the modified electrode resolved the overlapping voltammetric response of DA, UA and Trp into three well-defined voltammetric peaks with square wave voltammetry (SWV), which can be used for the simultaneous determination of these species in a mixture. The catalytic peak currents obtained from SWV were linearly dependent on the DA concentration in the range 2.0-10.0 mM and 10.0-1000.0 mM with correlation coefficients of 0.9993 and 0.9998, respectively. The detection limit (2s) for DA was 0.47 mM. The modified electrode showed good sensitivity and selectivity and has been applied to the determination of DA, UA and Trp simultaneously in real samples with satisfactory results.

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A novel counter electrode (CE) based on a silver and copper oxide nanocomposite is developed and characterized by XRD and FE-SEM. A polymeric system containing poly(3,4ethylenedioxythiophene) (PEDOT) is employed as the conductive polymer to prepare a transparent CE for a dye-sensitized solar cell (DSSC) device. Electrochemical analysis is used to study the catalytic activity of the reduction of triiodide ions in different DSSC-based CEs. To study the effect of photoelectrode modification on charge-transfer resistance, alternating current impedance spectroscopy is carried out. Power conversion efficiency and short-circuit current density (J SC ) increase from 8.01% to 9.06% and 16.18 to 17.79 mA/cm 2 , respectively, due to the significantly improved electrical conductivity and electrocatalytic activity of the novel PEDOT/Ag-CuO nanocomposite-based CE.

Clean-energy technologies have been welcomed due to environmental concerns and high fossil-fuel costs. Today, photovoltaic (PV) cells are among the most well-known technologies that are used today to integrate with buildings. Particularly, these cells have attracted the attention of researchers and designers, combined with the windows and facades of buildings, as solar cells that are in a typical window or facade of a building can reduce the demand for urban electricity by generating clean electricity. Among the four generations that have been industrialized in the development of solar cells, the third generation, including dye-sensitized solar cells (DSSCs) and perovskite, is used more in combination with the facades and windows of buildings. Due to the characteristics of these cells, the study of transparency, colour effect and their impact on energy consumption is considerable. Up to now, case studies have highlighted the features mentioned in the building combination. Therefore, this paper aims to provide constructive information about the practical and functional features as well as the limitations of this technology, which can be used as a reference for researchers and designers.