In recent years, vacancy-ordered halide double perovskites have emerged as promising non-toxic and stable alternatives for their lead-based counterparts in optoelectronic applications. In particular, vacancy ordered Cs₂PtI₆ has emerged as a star material because of its high absorption coefficient, band gap of 1.37 eV, and long minority carrier lifetime. Despite substantial experimental research on this new class of material, theoretical simulations of their device properties remain scarce. In this work, a novel n-i-p device architecture (FTO/SnO₂/Cs₂PtI₆/MoO₃/C) is theoretically investigated using a solar cell capacitance simulator (SCAPS-1D). Theoretical investigations are carried out in order to optimize the device performance structure by varying the perovskite and selective charge transport layer thickness, absorber and interface defect density, operating temperature, back contact, series and shunt resistance, respectively. The optimized device showed an impressive power conversion efficiency (PCE) of 23.52% at 300 K, which is higher than the previously reported values. Subsequent analysis of the device's spectral response indicated that it possessed 98.9% quantum efficiency (QE) and was visibly active. These findings will provide theoretical guidelines for enhancing the performance of Cs₂PtI₆-based photovoltaic solar cells (PSCs) and pave the way for the widespread implementation of environmentally benign and stable perovskites.

The use of perovskites in photovoltaic and related industries has achieved tremendous success over the last decade. However, there are still obstacles to overcome in terms of boosting their performance and resolving stability issues for future commercialization. The introduction of a new 2D material of halide perovskites is now the key advancement in boosting the solar energy conversion efficiency. The implication of a new 2D material (MXene) in perovskite solar cells has been initiated since its first report in 2018, showing excellent transparency, electrical conductivity, carrier mobility, superior mechanical strength, and tunable work function. Based on distinctive features at the hetero-interface, halide perovskite and MXene heterostructures (HPs/Mx) have recently exhibited exceptional improvements in both the performance and stability of perovskite solar cells. Furthermore, the wide families of HPs and MXene materials allow playing with the composition and functionalities of HP/Mx interfaces by applying rational designing and alterations. In this review a comprehensive study of implementing MXenes in perovskite solar cells is presented. First, the implementation of MXenes in perovskites as an additive, and then in charge extraction layers (HTL/ETL), is described in detail. It is worth noting that still only Ti₃C₂T_x, Nb₂CT_x,V₂CT_x MXene is being incorporated into perovskite photovoltaics. Finally, the present obstacles in the use of MXenes in PSCS are discussed, along with the future research potential. This review is expected to provide a complete and in-depth description of the current state of research and to open up new opportunities for the study of other MXenes in PSCs.

Two novel benzimidazole ligands ( E )-2-((4-(1 H -benzo[ d ]imidazole-2-yl)phenylimino)methyl)-6-bromo-4-chlorophenol and ( E )-1-((4-(1 H -benzo[ d ]imidazole-2-yl)phenylimino)methyl) naphthalene-2-ol and their Cu( ii ), Ni( ii ), Pd( ii ) and Zn( ii ) complexes were designed and synthesized.

The corrosion inhibitive capabilities of some ferrocene-based Schiff bases on aluminium alloy AA2219-T6 in acidic medium were investigated using Tafel polarization, electrochemical impedance spectroscopy (EIS), weight loss measurement, FT-IR spectroscopy and scanning electron microscopic (SEM) techniques. The influence of molecular configuration on the corrosion inhibition behavior has been explored by quantum chemical calculation. Ferrocenyl Schiff bases 4,4′-((((ethane-1,2-diylbis(oxy))bis(4,1-phenylene))bis(methaneylylidene))bis(azaneylylidene))bisferrocene (Fcua), 4,4′-((((ethane-1,2-diylbis(oxy))bis(2-methoxy-1,4-phenylene))bis(methaneylylidene))bis(azaneylylidene))bisferrocene (Fcub) and 4,4′-((((ethane-1,2-diylbis(oxy))bis(2-ethoxy-1,4-phenylene))bis(methaneylylidene))bis(azaneylylidene))bisferrocene (Fcuc) have been synthesized and characterized by FT-IR, ¹H and ¹³C NMR spectroscopic studies. These compounds showed a substantial corrosion inhibition against aluminium alloy in 0.1 M of HCl at 298 K. Fcub and Fcuc showed better anticorrosion efficiency as compared with Fcua due to the electron donating methoxy and ethoxy group substitutions, respectively. Polarization curves also indicated that the studied biferrocenyl Schiff bases were mixed type anticorrosive materials. The inhibition of the aluminium alloy surface by biferrocenyl Schiff bases was evidenced through scanning electron microscopy (SEM) studies. Semi-empirical quantum mechanical studies revealed a correlation between corrosion inhibition efficiency and structural functionalities.

Two new effective corrosion inhibitors, namely N-(n-octyl)-3-methylpyridinium bromide (Py8) and N-(n-dodecyl)-3-methylpyridinium bromide (Py12), have been presented. The cationic pyridinium-based surfactants were analyzed for the corrosion protection of general purpose steel (EN3B) against a strong corrosive media (3.5% NaCl, pH 1.5). The results of the electrochemical measurements, i.e., Tafel polarization, linear polarization resistance (LPR) and electrochemical impedance spectroscopy (EIS) revealed a mixed-type behavior of both inhibitors, and the maximum inhibition efficiency (IE) achieved with Py8 and Py12 was 85% and 82%, respectively. The process of adsorption of synthesized inhibitors followed the Langmuir adsorption isotherm, and a higher value of K_ads highlighted the existence of strong interaction between inhibitors and the EN3B mild steel surface. Furthermore, the values of ΔG°_ads were calculated to be −32 kJ mol⁻¹ for Py8 and −33 kJ mol⁻¹ for Py12, indicating the coexistence of both physisorbed and chemisorbed molecules. The surface morphology of EN3B mild steel samples was observed by scanning electron microscopy (SEM) and atomic force microscopy (AFM), where the reduced surface roughness in the presence of Py8 and Py12 in chloride media further supported the evidence of an efficient inhibition process. Density functional theory (DFT) calculations reveal excellent correlation with the experimental results, with Py8 showing superior corrosion inhibition potential, signifying that the alkyl chain length and intramolecular charge transfer are crucial factors in deciding the inhibition performance of the synthesized cationic surfactants. Furthermore, this study proposes the mechanism for the adsorption of the surfactant-based inhibitors over the EN3B mild steel surface, which leads to the formation of an effective and protective anticorrosive film.