Vivek Kumar Shukla

Conventional three-dimensional (3D) perovskite materials are renowned for their exceptional optoelectronic properties, making them highly suitable for photodetector (PD) applications. However, these materials often suffer from stability issues, as their structural and functional integrity deteriorates under environmental stressors such as moisture, thermal fluctuations, and ultraviolet (UV) exposure. Low-dimensional perovskites generally exhibit somewhat lower optoelectronic performance than 3D perovskites but offer significantly enhanced environmental stability. Notably, the fabrication of pure 2D perovskite materials can be synthesized under ambient conditions whereas 3D perovskites typically require controlled environments, such as a nitrogen-filled glovebox, to prevent degradation during formation. In this study, we have fabricated a pure 2D halide perovskite, 2-thiopheneethylammonium lead iodide (TEA)2PbI4 on glass substrates using a solution-processed method under ambient conditions (RH ≈ 55% ± 10%). To gain deeper insights into the influence of the thiophene group relative to other 2D perovskite materials, we carried out structural, morphological, and optical characterizations.

The effect of two activating agents namely phosphoric acid (H₃PO₄) and iron (III) chloride (FeCl₃) is investigated, in activation of carbon obtained from Tinospora cordifolia. The structural and morphological properties of the synthesized activated carbons were investigated using X-ray diffraction, scanning electron microscopy, Raman spectroscopy, and Brunauer–Emmett–Teller analysis. A notable yield of ∼60 % of the activated carbons was obtained using a simple and cost-effective approach of chemical activation followed by the thermal activation method. The electrochemical properties of the activated carbons were studied for electric double-layer capacitor application. The electrochemical impedance spectroscopy, galvanostatic charge–discharge and cyclic voltammetry studies revealed superior charge transfer properties of the carbon activated with H₃PO₄. The capacitor comprising carbon activated with H₃PO₄ electrodes shows higher specific capacity of 58 F g⁻¹ at 1 A g⁻¹ than that of carbon activated with FeCl₃ (37.5 F g⁻¹). The optimized capacitor delivers superior power density and energy density of 2 kW kg⁻¹ and 28.33 W h kg⁻¹, respectively.

The present study has explored the electronic properties of Organic-inorganic mixed halide-based perovskites using density functional theory. The Quantum Espresso simulation package with PBE parameterization within the generalized gradient approximation (GGA) has been used in this work. The findings reveal that the addition of halogens (bromide and chlorine) to compound CH₃NH₃PbI₃ for all the possible substituted halides may cause the shifting of energy bands in the band structure and thus change the bandgap. Hence, this calculation may be used to design perovskite solar cell material with varied electronic structure.

Correction for ‘Structure–property relationships of diketopyrrolopyrrole- and thienoacene-based A–D–A type hole transport materials for efficient perovskite solar cells’ by Gururaj P. Kini et al., New J. Chem., 2022, DOI: https://doi.org/10.1039/d2nj00294a.