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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The development of organic electron acceptor materials is one of the key factors for realizing high-performance organic solar cells (OSCs). Nonfullerene electron acceptors, compared to traditional fullerene acceptor materials, have gained much impetus owing to their better optoelectronic tunabilities and lower cost, as well as higher stability. Therefore, 5 three-dimensional (3D) cross-shaped acceptor materials having a spirobifullerene core flanked with 2,1,3-benzothiadiazole are designed from a recently synthesized highly efficient acceptor molecule SF(BR) 4 and are investigated in detail with regard to their use as acceptor molecules in OSCs. The density functional theory (DFT) and time-dependent DFT (TDDFT) calculations have been performed for the estimation of frontier molecular orbital (FMO) analysis, density of states analysis, reorganization energies of electron and hole, dipole moment, opencircuit voltage, photo-physical characteristics, and transition density matrix analysis. In addition, the structure-property relationship is studied, and the influence of end-capped acceptor modifications on photovoltaic, photo-physical, and electronic properties of newly selected molecules (H1-H5) is calculated and compared with reference (R) acceptor molecule SF(BR) 4. The structural tailoring at terminals was found to effectively tune the FMO band gap, energy levels, absorption spectra, open-circuit voltage, reorganization energy, and binding energy value in selected molecules H1 to H5. The 3D cross-shaped molecules H1 to H5 suppress the intermolecular aggregation in PTB7-Th blend, which leads to high efficiency of acceptor material H1 to H5 in OSCs. Consequently, better optoelectronic properties are achieved from designed molecules H1 to H5. It is proposed that the conceptualized molecules are superior than highly efficient spirobifullerene core-based SF(BR) 4 acceptor molecules and, thus, are recommended to experiments for future developments of highly efficient solar cells.

Gas sensing materials have been widely explored recently owing to their versatile environmental and agriculture monitoring applications. The present study advocates the electronic response of Zn-decorated inorganic B 12 P 12 nanoclusters to CO 2 gas. Herein, a series of systems CO 2 −Zn−B 12 P 12 (E1−E4) are designed by adsorption of CO 2 on Zn-decorated B 12 P 12 nanoclusters, and their electronic properties are explored by density functional theory. Initially, placement of Zn on B 12 P 12 delivers four geometries named as D1−D4, with adsorption energy values of −57.12, −22.94, −21.03, and −14.07 kJ/mol, respectively, and CO 2 adsorption on a pure B 12 P 12 nanocage delivers one geometry with an adsorption energy of −4.88 kJ/mol. However, the interaction of CO 2 with D1−D4 systems confers four geometries named as E1 (E ad = −75.12 kJ/mol), E2 (E ad = −25.89 kJ/mol), E3 (E ad = −42.43 kJ/mol), and E4 (E ad = −28.73 kJ/mol). Various electronic parameters such as dipole moment, molecular electrostatic potential analysis, frontier molecular orbital analysis, Q NBO , global descriptor of reactivity, and density of states are also estimated in order to understand the unique interaction mechanism. The results of these analyses suggested that Zn decoration on B 12 P 12 significantly favors CO 2 gas adsorption, and a maximum charge separation is also noted when CO 2 is adsorbed on the Zn−B 12 P 12 nanocages. Therefore, the Zn-decorated B 12 P 12 nanocages are considered as potential candidates for application in CO 2 sensors.

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This work was inspired by a previous report [Janjua, M. R. S. A. Inorg. Chem. 2012, 51, 11306–11314] in which the optoelectronic properties were improved with an acceptor bearing heteroaromatic rings. Herein, we have designed four novel Y-series non-fullerene acceptors (NFAs) by end-capped acceptor modifications of a recently synthesized 15% efficient Y21 molecule for better optoelectronic properties and their potential use in solar cell applications. Density functional theory (DFT) along with time-dependent density functional theory (TDDFT) at the B3LYP/6-31G(d,p) level of theory is used to calculate the band gap, exciton binding energy along with transition density matrix (TDM) analysis, reorganizational energy of electrons and holes, and absorption maxima and open-circuit voltage of investigated molecules. In addition, the PM6:YA1 complex is also studied to understand the charge shifting from the donor polymer PM6 to the NFA blend. Results of all parameters suggest that the DA’D electron-deficient core and effective end-capped acceptors in YA1–YA4 molecules form a perfect combination for effective tuning of optoelectronic properties by lowering frontier molecular orbital (FMO) energy levels, reorganization energy, and binding energy and increasing the absorption maximum and open-circuit voltage values in selected molecules ( YA1–YA4) . The combination of extended conjugation and excellent electron-withdrawing capability of the end-capped acceptor moiety in YA1 makes YA1 an excellent organic solar cell (OSC) candidate owing to promising photovoltaic properties including the lowest energy gap (1.924 eV), smallest electron mobility (λ e = 0.0073 eV) and hole mobility (λ h = 0.0083 eV), highest λ max values (783.36 nm (in gas) and 715.20 nm (in chloroform) with lowest transition energy values ( E x ) of 1.58 and 1.73 eV, respectively), and fine open-circuit voltage ( V oc = 1.17 V) with respect to HOMO PM6 –LUMO acceptor . Moreover, selected molecules are observed to have better photovoltaic properties than Y21 , thus paving the way for experimentalists to look for future developments of Y-series-based highly efficient solar cells.

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