Efficient One-Step Synthesis of a Pt-Free Zn0.76Co0.24S Counter Electrode for Dye-Sensitized Solar Cells and Its Versatile Application in Photoelectrochromic Devices.

In this study, we synthesized a ternary transition metal sulfide, Zn0.76Co0.24S (ZCS-CE), using a one-step solvothermal method and explored its potential as a Pt-free counter electrode for dye-sensitized solar cells (DSSCs). Comprehensive investigations were conducted to characterize the structural, morphological, compositional, and electronic properties of the ZCS-CE electrode. These analyses utilized a range of techniques, including X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. The electrocatalytic performance of ZCS-CE for the reduction of I3- species in a symmetrical cell configuration was evaluated through electrochemical impedance spectroscopy and cyclic voltammetry. Our findings reveal that ZCS-CE displayed superior electrocatalytic activity and stability when compared to platinum in I-/I3- electrolyte systems. Furthermore, ZCS-CE-based DSSCs achieved power conversion efficiencies on par with their Pt-based counterparts. Additionally, we expanded the applicability of this material by successfully powering an electrochromic cell with ZCS-CE-based DSSCs. This work underscores the versatility of ZCS-CE and establishes it as an economically viable and environmentally friendly alternative to Pt-based counter electrodes in DSSCs and other applications requiring outstanding electrocatalytic performance.

A Morphological Study of Solvothermally Grown SnO2 Nanostructures for Application in Perovskite Solar Cells.

Tin(IV) oxide (SnO2) nanostructures, which possess larger surface areas for transporting electron carriers, have been used as an electron transport layer (ETL) in perovskite solar cells (PSCs). However, the reported power conversion efficiencies (PCEs) of this type of PSCs show a large variation. One of the possible reasons for this phenomenon is the low reproducibility of SnO2 nanostructures if they are prepared by different research groups using various growth methods. This work focuses on the morphological study of SnO2 nanostructures grown by a solvothermal method. The growth parameters including growth pressure, substrate orientation, DI water-to-ethanol ratios, types of seed layer, amount of acetic acid, and growth time have been systematically varied. The SnO2 nanomorphology exhibits a different degree of sensitivity and trends towards each growth factor. A surface treatment is also required for solvothermally grown SnO2 nanomaterials for improving photovoltaic performance of PSCs. The obtained results in this work provide the research community with an insight into the general trend of morphological changes in SnO2 nanostructures influenced by different solvothermal growth parameters. This information can guide the researchers to prepare more reproducible solvothermally grown SnO2 nanomaterials for future application in devices.

Nanostructured flower-shaped CuCo2S4 as a Pt-free counter-electrode for dye-sensitized solar cells.

We demonstrated a solvothermally prepared cost-effective, mesoporous, and high surface area nanostructured flower-shaped CuCo2S4 counter-electrode for dye-sensitized solar cells. The new counter electrode exhibited comparable results with a traditional Pt-based counter electrode, 7.56% vs. 7.42%, respectively. The electrochemical analysis demonstrated superior electrocatalytic activity of the product, which was stable even after 6 months of aging.

Crystal structure of 5,15-bis-(4-methyl-phen-yl)-10,20-bis-(4-nitro-phen-yl)porphyrin nitro-benzene disolvate.

The whole mol-ecule of the title porphyrin, C46H32N6O4·2C6H5NO2, which crystallized as a nitro-benzene disolvate, is generated by inversion symmetry. The porphyrin macrocycle is almost planar, the maximum deviation from the mean plane of the non-hydrogen atoms is 0.097 (2) Å. The aryl rings at the meso positions are inclined to this mean plane by 74.84 (6)° for the nitro-phenyl rings and 73.37 (7)° for the tolyl rings. In the crystal, the porphyrin mol-ecules are linked by C-H⋯O hydrogen bonds, forming chains along [100]. The solvent mol-ecules are also linked by C-H⋯O hydrogen bonds, forming chains along [100]. Inter-digitation of the p-tolyl groups along the c axis creates rectangular channels in which the solvent mol-ecules are located.