A novel, sequential method of dip-coating a ZnO covered mesoporous TiO2 electrode was performed using a non-halide lead precursor in an aqueous system to form a nanoscale perovskite film. The introduction of a ZnO interfacial layer induced significant adsorption in the non-halide lead precursor system. An efficient successive solid-state ion exchange and reaction process improved the morphology, crystallinity, and stability of perovskite solar cells. Improved surface coverage was achieved using successive ionic layer adsorption and reaction processes. When all sequential dipping conditions were controlled, a notable power conversion efficiency of 12.41% under standard conditions (AM 1.5, 100 mW·cm−2) was achieved for the perovskite solar cells fabricated from an aqueous non-halide lead precursor solution without spin-casting, which is an environmentally benign and low-cost manufacturing processes.

Nanostructured gas sensors find diverse applications in environmental and agricultural monitoring. Herein, adsorption of phosgene (COCl 2 ) on pure and copper-decorated B 12 N 12 (Cu−BN) is analyzed through density functional theory (DFT) calculations. Adsorption of copper on B 12 N 12 results in two optimized geometries, named Cu@b 66 and Cu@b 64 , with adsorption energies of −193.81 and −198.45 kJ/mol, respectively. The adsorption/interaction energies of COCl 2 on pure BN nanocages are −9.30, −6.90, and −3.70 kJ/mol in G1, G2, and G3 geometries, respectively, whereas the interaction energies of COCl 2 on copper-decorated BN are −1.66 and −16.95 kJ/mol for B1 and B2, respectively. To examine the changes in the properties of pure and Cu−BN nanocages, geometric parameters, dipole moment, Q NBO , frontier molecular orbitals, and partial density of states (PDOS) are analyzed to comprehensively illustrate the interaction mechanism. The results of these parameters reveal that COCl 2 binds more strongly onto copper-doped BN nanocages. Moreover, a higher charge separation is observed in COCl 2 −Cu−BN geometries as compared to copper-decorated BN geometries. Therefore, these nanocages may be considered as potential candidates for application in phosgene sensors.

The increasing demand of energy expedited the development of efficient photovoltaic materials.Herein, five push‐pull donor materials (D1‐D5) having N,N‐diethylaniline as donor moiety and rhodanine‐3‐acetic as acceptor group are designed to be used as donor molecules in organic solar cells (OSCs). The bridging core modification of recently synthesized MR3 molecule (reference R) has been made with different π‐spacers namely thiazole (B1), thieno[3,2‐b]thiophene (B2), thiazolo[5,4‐d] thiazole (B3), 2‐(thiophen‐2‐yl)thiophene (B4) and 5‐(thiazol‐5yl)thiazole (B5). The structure–property relationship is studied and influence of bridging core modifications on photovoltaic, photophysical and electronic properties of D1‐D5 are calculated and compared with reference R.The DFT and TDDFT calculations have been performed for the estimation of frontier molecular orbital (FMO) analysis, density of states (DOS) graphs, reorganization energies of electron and hole, open circuit voltage, photophysical characteristics, transition density matrix (TDM) surfaces and charge transfer analysis.Designed molecules exhibit better and comparable optoelectronic properties than synthesized reference molecules. Among all investigated molecules, D5 is proven as best candidate for OSCs application due to its promising photovoltaic properties including lowest band gap (2.24 eV), small electron mobility (λe=0.0056 eV), small hole mobility (λh=0.0046 eV), low binding energy (Eb=0.21 eV), highest λmax values 610.76 nm (in gas) 670.22 nm (in acetonitrile) and high open circuit voltage (Voc=1.17 V) with respect to HOMOdonor–LUMOPC61BM. This theoretical framework demonstrates that bridging core modification is a simple and effective alternative strategy to achieve the desirable optoelectronic properties. Furthermore, conceptualized molecules are superior and thus are recommended to experimentalist for out‐looking future developments of highly efficient solar cells.

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In the present investigation, quantum chemical calculations have been performed in a systematic way to explore the optoelectronic, charge transfer, and nonlinear optical (NLO) properties of different bis­(dicyanomethylene) end-functionalized quinoidal oligothiophenes. The effect of different conformations (linking modes of thiophene rings) on conformational, optoelectronic, and NLO properties are studied from the best-performed dimer to octamer. The optical and NLO properties of all the selected systems (1–7) are calculated by means of density functional theory (DFT) methods. Among all the designed compounds, the largest linear isotropic (αiso) polarizability value of 603.1 × 10–24 esu is shown by compound 7 which is ∼12, ∼16, ∼9, ∼11, ∼10, and ∼4 times larger as compared to compounds 1–6, respectively. A relative investigation is performed considering the expansion in third-order NLO polarizability as a function of size and conformational modes. Among all the investigated systems, system 7 shows the highest value of static second hyperpolarizability ⟨γ⟩ with an amplitude of 7607 × 10–36 esu at the M06/6-311G** level of theory, which is ∼521, ∼505, ∼38, ∼884, ∼185, and ∼15 times more than that of compounds 1–6, respectively. The extensively larger ⟨γ⟩ amplitude of compound 7 with higher oscillator strength and lower transition energy indicates that NLO properties are remarkably dependent upon linking modes of thiophene rings and its chain length. Furthermore, to trace the origin of higher nonlinearities, TD-DFT calculations are also performed at the same TD-M06/6-311G** level of theory. Additionally, a comprehensive understanding of the effect of structure/property relationship on the NLO polarizabilities of these investigated quinoidal oligothiophenes is obtained through the inspection of Frontier molecular orbitals, the density of states (TDOS and PDOS), and molecular electrostatic potential diagrams including the transition density matrix. Hence, the current examination will not just feature the NLO capability of entitled compounds yet additionally incite the interest of experimentalists to adequately modify the structure of these oligothiophenes for efficient optical and NLO applications.

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