The synthesis, photophysical and electrochemical studies of symmetrical phthalocyanines linked thiophene substituents

Perovskite Solar Cells Based on Polymerized Chlorophyll Films as Environmentally Friendly Hole-Transporting Layers

Hole-transporting layers (HTLs) play a crucial role in the performance of inverted, p-i-n perovskite solar cells (PSCs). Chlorophylls (Chls) are naturally abundant organic photoconductors on earth, with good charge carrier mobility and appropriate Fermi energy levels that make them promising candidates for use in photovoltaic devices. However, Chls films prepared using the solution method exhibit lower carrier mobility compared to other organic polymer films, which limits their application in PSCs. To address this issue, Chls molecules are chemically linked to reduce the charge transfer barrier, thus the transfer of charges between molecules is transformed to intramolecular charge transfer. This study synthesizes and characterizes two polymerized Chl films, PolyCuChl and PolyNiChl, as HTLs of CH3 NH3 PbI3 -based PSCs. PSCs based on the electrochemical polymerization of PolyChl HTLs demonstrate an enhanced power conversion efficiency (PCE) of up to 19.0%, which is the highest efficiency among devices based on Chl materials. Furthermore, these devices demonstrated exceptional long-term stability. These results highlight the potential of polymerized Chl films as a viable alternative to conventional HTLs in PSCs. The approach utilizes abundant, environmentally friendly, and versatile Chl derivatives, and can be extended to develop next-generation HTL materials for improved PSC performance.

Squaraine dye/Ti3C2Tx MXene organic-inorganic hybrids for photocatalytic hydrogen evolution

MXenes, a new family of 2D nanostructured materials, have been widely studied in the field of artificial photosynthesis due to their outstanding physicochemical properties. In this work, a series of 2,4-bis[4-(N,N-dibutylamino)phenyl] squaraine (SQ) derivatives with different number of hydroxyl groups were hybridized with Ti₃C₂T_x MXene nanosheets, and the organic-inorganic hybrid photocatalysts were applied for water-splitting hydrogen evolution. The mass ratios of SQ@Ti₃C₂T_x were optimized to 4 wt% for each SQ, and the best hydrogen evolution reaction (HER) rate of 28.6 μmol h^-1 g^-1 was achieved by SQ-3 with four OH groups. The photocatalytic ability of the hybrid comes from the outstanding light harvesting of SQ dye, sufficient active sites of Ti₃C₂T_x, and efficient separation and transfer of the photogenerated charges via heterojunction between SQ aggregates and Ti₃C₂T_x. This work firstly demonstrates an example of SQ sensitizer combined with MXene for hydrogen generation, which provides a new insight to further explore the MXene-based hybrid nanomaterials for water splitting hydrogen evolution.

Ti3C2Tx MXene nanosheets hybridized with bacteriochlorin–carotenoid conjugates for photocatalytic hydrogen evolution

Development of efficient photocatalysts with a wide spectral range for the photocatalytic hydrogen evolution reaction (HER) is a promising way to address the current energy and environmental crises.

Zinc(II) phthalocyanine fused in peripheral positions octa-substituted with alkyl linked carbazole: Synthesis, electropolymerization and its electro-optic and biosensor applications

Zinc(II) phthalocyanine fused in peripheral positions octa-substituted with alkyl linked carbazole has been prepared by cyclomerization reaction of 4,5-bis(6-carbazole-9-yl-hexylsulfanil)phthalonitrile in the presence of anhydro Zn(II) acetate and a strong organic base (DBU). Synthesis steps were optimized and higher efficiency synthesis was achieved. The purpose of combining of carbazole moieties with phthalocyanine on the peripheral position is to enhance some properties such as photo and electrochemical properties because of strong electron-donating properties of carbazole group. This molecule has been electrochemically polymerized and the electrical and optical properties of the resulting conductive polymer have been investigated. Amperometric detection was carried out following oxygen consumption at -0.7V vs. the Ag reference electrode in phosphate buffer (50mM, pH 6.0). The novel biosensor showed a linear amperometric response for glucose within a concentration range of 0.05mM to 1.5mM (LOD: 0.024mM). This result shows that modification of the proposed biosensor by copolymerization have provided to give perfect response to different glucose concentrations. Because of its superior spectral and electrochemical properties and contained zinc metal which can act as a mediator during biochemical reactions, this material has been used as a glucose biosensor platform to detection for real samples.

Preparation, characterization and investigation of photo-physical properties of thiophene-substituted rare-earth bisphthalocyanines

Three bis[octakis-(2-thienyl)phthalocyaninato] rare-earth metal(III) phthalocyanine complexes (Pc[Formula: see text]Pr, Pc[Formula: see text]Sm, Pc[Formula: see text]Gd) were synthesized for the first time. The new compounds were characterized by UV-vis, NMR, FT-IR, mass spectroscopies as well as elemental analysis and electrochemistry. Production of singlet oxygen was also estimated by 9,10-dimethylanthracene method.

An efficient perovskite solar cell with symmetrical Zn(ii) phthalocyanine infiltrated buffering porous Al2O3 as the hybrid interfacial hole-transporting layer

A new Zn(ii) phthalocyanine (Pc) based low bandgap HTM is introduced for perovskite solar cells. Steady state and time-resolved photoluminescence (PL) measurements indicated an evenly matched hole extraction efficiency between sym-HTPcH and spiro-OMeTAD. On account of the low film quality and resulting high recombination, Zn(ii) Pc normally cannot work as an effective HTM. We adopted insulating Al₂O₃ for the infiltration of sym-HTPcH to form a hybrid interfacial buffer layer, affording perovskite solar cells (PSCs) with an average PCE value of up to 12.3%, which is a significant improvement with respect to the control cell without the meso-Al₂O₃ layer (4.21%) and is the highest value ever reported for Zn(ii) phthalocyanine based devices under AM1.5G standard conditions. A hysteresis test revealed that our device structure with the new HTM exhibited a balanced charge extraction behaviour.