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Physical characteristics of LiXCl3 (X = Sn, Pb) have been reported by a first-principles approach in the CASTEP simulation code. In structural, LiSnCl3 and LiPbCl3 are in the cubic phase and dynamically stable according to the phonan calculation. The electronic properties revealed that LiSnCl3 and LiPbCl3 are semiconductors. The observed energy band gaps are direct band gap in the order of 1.35 eV and 2.29 eV for LiSnCl3, and LiPbCl3, respectively. Additionally, the electronic profile is briefly discussed in terms of the partial and total density of states. The lattice constant and electronic properties are well matched with the previous literature. The partial and total density of states confirms the degree of localization of electrons. Optical properties were examined in the energy range of 0–40 eV. The optical chracteristics such as reflectivity, refractive index, absorption, dielectric function, conductivity, and energy loss function are calculated. The maximum reflectivity is observed in LiPbCl3. Furthermore, the mechanical and elastic characteristics of the materials are estimated to ensure their reliability, stability, and ease of handling in optoelectronic applications. The physical properties reveal that the concerned compounds have direct and narrow energy band gap which are potentially useful in solar cell technology. [ABSTRACT FROM AUTHOR]

Hole-transporting materials (HTMs) have revolutionized the field of photovoltaics for solar cell devices. Herein, novel butterfly-shaped hole transport material (HTM) 2,7-DMPZ (R) containing twisted core unit is used to develop novel molecules (Q1–Q6) by fitting suitable donor groups at peripheral regions of 2,7-DMPZ. To investigate the power conversion efficiency (PCE) of Q1–Q6, different analyses, including optical, frontier molecular orbitals (FMOs), molecular electrostatic potential (MEP), density of states (DOS), transition density of states (TDM), and charge transfer (CT) analysis are employed using various density functional theory (DFT) and time-dependent-DFT (TD-DFT) approaches. Excitation, binding, and reorganization energy along with open-circuit voltage of Q1–Q6 molecules are estimated. The UV–Visible study elucidates that these molecules exhibited redshifts (329–343 nm) absorption higher and comparable with the R molecule (342 nm). The HOMO–LUMO gap of Q1–Q6 (5.31–5.38 eV) is also narrower than R (5.49 eV), indicating that designed molecules can show higher charge transfer than R, which can ultimately produce higher PCE values. In case of hole reorganization energy, the hole mobilities are found more valuable than R. For charge transfer analysis, the Q6 molecule is complexed with PC 6 1 BM acceptor polymer that shows promising charge transfer between the Q6/PC 6 1 BM complex. All studies illustrate that proposed molecules (Q1–Q6) have a great capacity to further improve the optical and photovoltaic parameters when they will be used in efficient organic (as donors) and perovskite (as HTM) solar cells and can show higher performances than R. Therefore, these newly designed molecules (Q1–Q6) rerecommended to the experimentalists for the synthesis to be employed as donors in organic and as HTMs in perovskite solar cells applications. Butterfly-shaped hole transport materials containing twisted core unit is used to develop new novel molecules (Q1–Q6) by fitting suitable donor groups at peripheral regions. To investigate the potential of these materials for photovoltaic devices, we performed various optical and photovoltaic characterizations theoretically. All studies show that proposed molecules (Q1–Q6) have a great capacity to further improve the optical and photovoltaic parameters when they will be used in an efficient organic (as donors) and perovskite (as HTM) solar cells applications. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM) enables the production of high value and high performance components with applications from aerospace to biomedical fields. We report here on the fabrication of poly(3-hexylthiophene): phenyl-C61-butyric acid methyl ester (P3HT:PCBM) thin films through the electrohydrodynamic atomization (EHDA) process and its integration as absorber layer for organic solar cells. Prior to the film fabrication, the optimization of the process was carried out by developing the operating envelope for the P3HT:PCBM ink to determine the optimal flow rate and the appropriate applied voltage to achieve a stable-cone deposition mode. The EHDA printed thin-film's topography, morphology and optical properties were systematically analyzed. The root-mean-square roughness was found to vary significantly with the annealing temperature and the flow rate and ranged from 1.938 to 3.345 nm. The estimated film mass and thickness were found between 3.235 and 23.471 mg and 597.5 nm to 1.60 µm, respectively. The films exhibited a broad visible absorption spectrum ranging from ~ 340 to ~ 600 nm, with a maximum peak λmax located at ~ 500 nm. As the annealing temperature and the flow rate were increased, discernible alterations in the PCBM clusters were consequently observed in the blends of the film and the size of the PCBM clusters has decreased by 3% while the distance between them was highly reduced by as much as 82%. [ABSTRACT FROM AUTHOR]

The end‐capped modification proves that it is an excellent attempt to improve the solar cells performances. Therefore, nowadays, many researchers are working to design new molecules for potential use in organic photovoltaics. Herein, we have modified new molecules (SA1–SA5) from the reference (R) for fullerene‐free solar cells. These novel molecules have lower excitation energy levels that make the easier excitation in the excited state. Additionally, SA1 to SA5 molecules exhibit excellent charge mobility due to the modification of an efficient core units. Geometric and physiochemical investigations indicate that the modeled molecules are beneficial for efficient organic solar cells. The estimation of frontier molecular orbitals analysis, reorganizational energy, photovoltaic characteristics, and charge transmission calculations was done using density functional theory calculations with B3LYP/6‐31G (d, p) basis set. Among all designed molecules, SA3 has emerged as the preferred choice because of its outstanding photovoltaic characteristics, which include a minimal bandgap of 2.03 eV and reorganization energy of electron and holes of 0.0095 and 0.0077 eV, correspondingly. The designed materials (SA1–SA5) displayed a high λ max values, that is, 693.54 nm (in gas) and 679.63 nm (in chloroform). This theoretical framework suggests that the required photovoltaic properties may be efficiently obtained by remodeling the new molecules. [ABSTRACT FROM AUTHOR]

Organic solar cells (OSCs) made of electron-acceptor and electron-donor materials have significantly developed in the last decade, demonstrating their enormous potential in cutting-edge optoelectronic applications. Consequently, we designed seven novel non-fused ring electron acceptors (NFREAs) (BTIC-U1 to BTIC-U7) using synthesized electron-deficient diketone units and reported end-capped acceptors, a viable route for augmented optoelectronic properties. The DFT and TDDFT approaches were used to measure the power conversion efficiency (PCE), open circuit voltage (Voc), reorganization energies (λh, λe), fill factor (FF), light harvesting efficiency (LHE) and to evaluate the potential usage of proposed compounds in solar cell applications. The findings confirmed that the photovoltaic, photophysical, and electronic properties of the designed molecules BTIC-U1 to BTIC-U7 are superior to those of reference BTIC-R. The TDM analysis demonstrates a smooth flow of charge from the core to the acceptor groups. Charge transfer analysis of the BTIC-U1:PTB7-Th blend revealed orbital superposition and successful charge transfer from HOMO (PTB7-Th) to LUMO (BTIC-U1). The BTIC-U5 and BTIC-U7 outperformed the reference BTIC-R and other developed molecules in terms of PCE (23.29% and 21.18%), FF (0.901 and 0.894), normalized Voc (48.674 and 44.597), and Voc (1.261 eV and 1.155 eV). The proposed compounds enclose high electron and hole transfer mobilities, making them the ideal candidate for use with PTB7-Th film. As a result, future SM-OSC design should prioritize using these constructed molecules, which exhibit excellent optoelectronic properties, as superior scaffolds. [ABSTRACT FROM AUTHOR]

One key strategy to further improve the power conversion efficiency (PCE) of organic solar cells (OSCs) is to incorporate various complementary functional groups in a molecule. Such strategies proved attractive for tuning the photovoltaic performances of the materials and can show a much higher absorption phenomenon with narrower band gaps. Despite the outstanding benefits, materials selection and their efficient modeling is also an extremely challenging job for the development of OSCs materials. In this manuscript, we proficiently developed an efficient series of small molecule-based non-fullerene acceptors (SM-NFAs) SN1-SN9 for OSCs and characterized by density functional theory (DFT) and time-dependent DFT (TD-DFT). The characteristics required to estimate electron and hole mobility, and open-circuit voltage (Voc) were investigated by optimizing the geometrical parameters, absorption spectra, exciton binding energy, frontier molecular orbitals (FMOs), electronic structures, and charge transfer rates. The outcomes of these materials showed that all newly constructed small-molecule-based non-fullerene acceptors exhibit broader and better absorption efficiency (λmax = 761 to 778 nm) and exciton dissociation, while much lower LUMO energy levels which may help to enhance the reorganizational energies. Further, a narrow bandgap also offers better photovoltaic properties. Hence, the designed molecules exhibited narrow bandgap values (Eg = 2.82 to 2.98 eV) which are lower than that of the reference molecule (3.05 eV). High Voc and photocurrent density values with lower excitation and binding energies eventually increase the PCEs of the OSC devices. The obtained results have shown that designed molecules could be effective aspirants for high-performance OSCs. Highlights: Half-moon-shaped fullerene-free acceptor molecules (SN1-SN9) are studied for organic solar cells applications. Significant lowering of energy gap with concomitant red-shifting of the absorption spectra is achieved with end-group engineering. The acceptors molecules show lower binding energy and excellent electron and hole reorganizational energies. All acceptor molecules have remarkable optoelectronic properties compared to reference R. [ABSTRACT FROM AUTHOR]

Development of novel materials for organic solar cells is a booming area of current research. Fused-ring electron accepters are the potential agents of revolution in organic photovoltaic devices and revealing high efficiency in organic solar cells. This study highlights the novel quad-rotor-shaped molecules as first example of efficient fused-ring non-fullerene acceptor materials with proficient photovoltaic parameters for their utilization in high-performance organic solar cells. First time, eight quad-rotor-shaped fused-ring electron accepters (QRFR-1–QRFR-8) are developed via modulating end-caps of experimentally synthesized (BFTT-TN) molecule (QRFR). Optoelectronic properties of proposed molecules are determined using frontier molecular orbitals (FMO), UV–Visible, density of state (DOS), overlap DOS (ODOS), transition density matrix (TDM) heat maps, open circuit voltage (Voc), binding energies (Eb), reorganization energy of electron (λe), hole (λh), charge transfer analysis, and compared with reference QRFR. All proposed fused-ring electron accepters disclose less energy gap and λmax in near IR region than QRFR after end-capped engineering. Highest Voc with respect to HOMOPM6–LUMOacceptor is found 1.66 V in QRFR-6 than QRFR (1.63 V). Eb values of QRFR-1–QRFR-8 are found better and comparable with QRFR. The λe is found smaller than QRFR in all molecules except QRFR-5. The proposed quad-rotor-shaped molecules exhibit proficient photovoltaic features and can serve as best candidate for organic solar cells when blended with PM6 film. This study not only enlightens the researchers to use end-capped reforms as effective tactic for designing materials, but also provides novel quad-rotor-shaped materials to experimentalist for synthesis and their usage in future application of organic solar cells. [ABSTRACT FROM AUTHOR]

The development of an effective building blocks considered the boon in constructing highly efficient nonfullerene electron acceptors (NFEAs). The first theoretical design and investigation of environmental-friendly groups for changing potential end-capped electron acceptor molecules for high-performance environmental-friendly OSCs is proposed in this study. We developed BTT-based A – π – D – π – A (acceptor–bridge–core–bridge–acceptor) type, neoteric Bat-shaped environmental-friendly acceptor molecules (K1–K6) for the first time by replacing the electronegative –F group of BTT with four electron-withdrawing (–CN, –COOCH3, –NO2, –Cl) groups. K1–K6 has its exciton-binding energy ( E b ), open-circuit voltage ( V oc ), frontier molecular orbital analysis (FMO), transition density matrix (TDM) analysis, electron and hole reorganization energy (λ e, λ h), density of state (DOS) graphs, and transition energy Ex values computed and compared to the recently proposed high-performance BTT molecule. According to the research, the photovoltaic, photo-physical and electrical applications of proposed molecules K1–K6 are comparable to those of R. When compared to reference R and proposed molecules, K6 tested to be the proverbial optoelectronic compound for OSCs due to its low E g (2.05 eV), lowest E x (1.57 eV), highest λ max values of 790.61 nm in CHCl3, 0.95 V value for V oc and comparable E b (0.482 eV). The superposition of orbitals and lucrative charge shift from the highest occupied molecular orbital (HOMO) (PTB7-Th) to the lowest unoccupied molecular orbital (LUMO) were verified by charge transfer study among the K6: PTB7-Th combine. As a result, the proposed molecules (K1–K6) with exceptional optoelectronic capabilities are suggested as the best harmless alternative materials for creating proficient and environmental-friendly OSCs. Benzotrithiophene-based bat-shaped non-fullerene acceptor materials (K1-K6) have been designed to enhance the photophysical and optoelectronics properties. These materials (K1-K6) along with reference (R) have been visualized theoretically. The photovoltaic and optoelectronic properties have been estimated with density functional theory (DFT) and time-dependent (TD-DFT) calculations, and this strategy is a criterion to design required photovoltaic materials for efficient OSCs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nine anthradithiophene-based photovoltaic compounds are designed for bulk heterojunction solar cells. • The optoelectronic properties were studied in detail using DFT and TDDFT calculations. • The FMO, MEP, UV–Visible, DOS, TDM, and Voc, and are performed. • All investigated molecules exhibit remarkable optoelectronic properties. • Investigated molecules are recommended for future solar cell applications. The optoelectronic characteristics of fullerene-free photovoltaic compounds hold significant value in photonics and optoelectronics applications. To obtain the optimal candidate for modernized hi-tech purposes and to meet the rising requirement of photovoltaic blends for future solar cell applications, the current study centered on simulating and conducting DFT-analysis-of-synthesized anthradithiophene-based reference (RS) and nine tailored molecules (ZHS1–ZHS9). DFT and time-dependent-DFT methods were utilized to determine the photochemical, optoelectronic, and photovoltaic parameters such as absorption behavior, energy gaps, charge transfer capabilities, TDM analysis, reorganizational energy, charge transfer complex ZHS5:PC 61 BM study for ZHS1–ZHS9 and RS. The absorption maxima of ZHS1–ZHS9 molecules resulted in red shifting (680–816 nm) compared to the synthesized RS reference molecule (454 nm). The distribution of electron density on various molecular components is confirmed by the DOS and FMOs analysis. All tailored molecule possesses less energy gap, while ZHS5 gave the narrowest bandgap (1.21 eV) with less binding energy (0.19 eV) as well as excitation energy (1.02 eV) as compared to the reference molecule. The developed molecules carried larger open-circuit voltage (Voc = 1.04–1.88 V) and fill factor (FF=0.93) than the reference molecule Voc = 0.47 V and FF=0.803594, indicating that they are better suited to drawing more electric current. The ZHS5:PC 61 BM blend study and overall outcomes showed that these planned donor molecules are photo and thermally stable efficient solar cell candidates, and their ongoing research has the potential to result in high-performance photovoltaic systems. Thus, this work encouraged experimenters to create the suggested solar cell materials for cutting-edge optoelectronic high-tech uses. [ABSTRACT FROM AUTHOR]

Porphyrin‐based non‐fullerene acceptors (NFAs) have shown pronounced potential for assembling low‐bandgap materials with near‐infrared (NIR) characteristics. Herein, panchromatic‐type porphyrin‐based molecules (POR1–POR5) are proposed by modulating end‐capped acceptors of a highly efficient porphyrin‐based NFA PORTFIC(POR) for organic solar cells (OSCs). Quantum chemical structure‐property relationship has been studied to discover photovoltaic and optoelectronic characteristics of POR1–POR5. Results show that optoelectronic properties of the POR1–POR5 are better in all aspects when compared with the reference POR. All proposed NFAs particularly POR5 proved to be the preferable porphyrin‐based NIR sensitive NFA for OSCs applications owing to lower energy gap (1.56 eV), transition energy (1.11 eV), binding energy (Eb=0.986 eV), electron mobility (λe=0.007013Eh), hole mobility (λh=0.004686 Eh), high λmax=1116.27 nm and open‐circuit voltage (Voc=1.96 V) values in contrast to the reference POR and other proposed NFAs. This quantum chemical insight provides sufficient evidence about excellent potential of the proposed porphyrin‐based NIR sensitive NFA derivatives for their use in OSCs. [ABSTRACT FROM AUTHOR]

• Ten novel compounds with naphthalene-fused octacyclic core are designed for solar cell applications. • Electronic, photophysical and photovoltaic features are explored using computational tools. • Augmented optoelectronic properties are predicted in proposed molecules. • The designed compounds are recommended for stable and efficient organic solar cells. To meet the growing need for high-efficiency photovoltaic materials in today's high-tech applications, ten acceptor molecules (SH01-SH10) with naphthalene-fused octacyclic electron-donating central core NITT are proposed. End-capped structural-alterations on reference R (NITT-2F) with strong electron-drawing groups (A01-A10) are performed for attaining improved optoelectronic characteristics and possible applications in organic solar cells (OSCs). In comparison to the reference R (NITT-2F), key parameters such as FMO analysis, energy gap (E gap), open-circuit voltage (V OC), absorption spectra (λ max), excitation energy (E x), transition density matrix (TDM) with binding energy (E b), the density of states (DOS), reorganization energy of the electron (λ e) and hole (λ h), and charge transfer with PM6 donor substance are perceived. It is found that all proposed molecules (SH01-SH10) have a reduced energy gap (2.104–1.901 eV), a broader absorption spectrum (707–820 nm), and smaller excitation energy (1.75–1.51 eV) as compared to reference molecule NITT-2F values 2.132 eV, 675 nm and 1.79 eV respectively. The significant charge transfers and 0.23 eV decrease in the E gap is noted for the designed molecule SH05. Results confirmed that all proposed molecules, especially SH05 could be an excellent choice for OSCs candidate due to the combination of strong electron-withdrawing effect in end-capped acceptor unit and extended conjugation, as well as its promising photovoltaic properties, which include the lowest E gap (1.901 eV), highest λ max (820 nm (in chloroform) and 729 nm (in gas phase)) with E x values of 1.51 and 1.70 eV respectively, slightest electron mobility (λ e = 0.0090 eV) and hole mobility (λ h = 0.0073 eV), highest ionization potential (6.826 eV) and electron affinity (3.384 eV), and fine value of V OC =1.02 V with respect to (ǀEPM6 HOMO ǀ - ǀESH05 LUMO ǀ). End-capped acceptor alterations are an acceptable way to attain the desired optoelectronic characteristics demonstrated in this research work. This study can be essential in achieving efficient novel non-fullerene OSCs with higher performance, low cost, and higher optical absorption coefficient. Thus, proposed molecules (SH01-SH10) with proficient electron and hole transfer mobilities and optoelectronic features are recommended to develop higher-efficiency solar cells. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Isoindacendodithiophene-based ten novel photovoltaic materials are proposed. • The optoelectronic properties are computed using DFT based TDM, FMO, MEP, DOS, charge transfer, reorganizational energy analysis. • The investigated compounds exhibited excellent photovoltaic attributes with PCE (∼15.97 %), fill factor (54.67), and open-circuit voltage (1.41 V). • Proposed photovoltaic materials are recommended as fine candidates for future solar cell technology. Enhancing photovoltaic materials with improved power conversion efficiency (PCE), conduction band, and electrochemical attributes for organic solar cell (OSC) applications is a forefront area of research. This study is centered on the simulating and computational characterization of iso-indacenodithiophen (iso-IDTIC)-based new molecules (AF01-AF10) to obtain optimal candidates for high-performance OSCs. The proposed molecules have excellent PCE (∼15.97 %), fill factor (54.67), and open-circuit voltage V oc = 1.41 V, better than previous reports. DFT simulations-based analysis, including TDM, FMO, MEP, DOS, V oc , reorganization energies of hole and electron, and charge transfer analysis, were employed to confirm and comprehend the photovoltaic properties of proposed molecules. Reduction in energy gap (2.30–2.50 eV), binding energy (0.28–0.29 eV), enhanced λ max (586–686 nm) with HOMO → LUMO (>96 %) charge transfer was examined as compared to R(2.54 eV, 608 nm). Moreover, higher excitation dissociation rate, TDM, HOMO Donor -LUMO Acceptor blend study, and reorganizational energy for electron and hole results confirmed that proposed molecules are efficient photovoltaic candidates for future solar energy applications. [ABSTRACT FROM AUTHOR]

The development of novel photovoltaic materials for solar cell applications is a fascinating area of current research. Star‐shaped materials with promising photovoltaic features have attracted scientists for boosting the progress of organic solar cells (OSCs). Herein, seven novel star‐shaped molecules (DA1‐DA7) are developed quantum chemically from the experimentally synthesized BTI(2 T‐DCV‐Hex)3 molecule. The open‐circuit voltage (Voc), transition density matrix heat maps, density of state (DOS), overlap DOS, frontier molecular orbital, UV−visible, binding energy (Eb), hole (λh) and electron (λe) reorganizational energy, and highest occupied molecular orbital (HOMO)donor−lowest unoccupied molecular orbital (LUMO)PC61BM charge transfer analysis are performed to explore the optoelectronic properties. Newly developed molecules exhibit promising optoelectronic features with reduced energy gap (2.43−1.97 eV), transition energy (1.89−1.45 eV), λe (0.00149328−0.00101405 Eh), λh (0.0066471−0.0028843 Eh), broadened λmax (655−856 nm), and high Voc (2.07−1.65 V), as compared with reference BTI(2 T‐DCV‐Hex)3 values 2.82 eV, 2.28 eV, 0.00176501 Eh, 0.0060877 Eh, and 544 nm, 1.65 V, respectively. The developed molecules have proficient hole and electron transfer mobilities and can serve as best candidates when blended with PC61BM film. These eye‐catching results recommend the novel star‐shaped compounds for future development of high‐performance OSCs. [ABSTRACT FROM AUTHOR]

Organic photovoltaic solar cells are being designed to offer a low energy photovoltaic (PV) solution. Optimizing the molecular backbone is one the most important technique for improving the photovoltaic characteristic of A‐D‐A type small active layer molecules. Herein, we have designed and theoretical characterized six new molecules by end‐capped and bridging core modifications of recently synthesized molecule BFHIC‐4F. Enhancement in photovoltaic, optoelectronic and physio‐chemical properties of newly designed molecules are seen by doing such modifications. Different advanced quantum chemical techniques have been employed to evaluate the performance of newly planned molecules. Large open circuit voltage and narrow band gap suggested that the designed molecules are efficient aspirants for solar cell applications. Moreover, maximum absorption capability in near‐infra‐red (NIR) region is observed for these newly designed molecules. To sum up, outcomes of all analyses advocated that the designed molecules are efficient candidates for solar cell applications. [ABSTRACT FROM AUTHOR]

Non-fullerene small molecular acceptors (NFSMAs) exhibit promising photovoltaic performance which promoted the rapid progress of organic solar cells (OSCs). In this study, an attempt is done to explore indenothiophene-based high-performance small molecular electron acceptors for organic solar cells. We have designed five acceptor molecules (M1–M5) with strong donor moiety indenothiophene linked to five different end-capped group acceptor moieties: diflouro-2-methylene-3-oxo-2,3-dihydroindene-1-ylidene)malononitrile (A1), 1-(dicyanomethylene)-2-methylene-3-oxo-2,3-dihydro-1H-indene-5,6-dicarbonitrile (A2), methyl-6-cyano-3-(dicyanomethylene)-2-methylene-1-oxo-2,3-dihydro-1H-indene-5-carboylate (A3), 2-(6-cyano-5-fluoro-2-methylene-3-oxo-2,3 dihydro-1H-indene-1-ylidene)malononitrile (A4), and (Z)-methyl 3-(benzo [c][1,2,5]thiadiazol-4-yl)-2-cyanoacrylate (A5) respectively. The structure–property relationship was studied and effects of structural modification on the optoelectronic properties of these acceptors (M1–M5) were determined systematically by comparing it with reference molecule R, which is recently reported as excellent non-fullerene-based small acceptor molecule. Among all designed molecules, M5 is proven as a suitable candidate for organic solar cell applications due to better photovoltaic properties including narrow HOMO-LUMO energy gap (2.11 eV), smallest electron mobility (λe = 0.0038 eV), highest λmax values (702.82 nm in gas) and (663.09 nm in chloroform solvent) and highest open-circuit voltage (Voc = 1.49 V) with respect to HOMOPTB7-Th–LUMOacceptor. Our results indicate that introducing more end-capped electron-accepting units is a simple and effective alternative strategy for the design of promising NFSMAs. This theoretical framework also proves that the conceptualized NFSMAs are superior and thus are recommended for the future construction of high-performance organic solar cell devices. [ABSTRACT FROM AUTHOR]

Non-fullerene based organic compounds are considered promising materials for the fabrication of modern photovoltaic materials. Non-fullerene-based organic solar cells comprise of good photochemical and thermal stability along with longer device lifetimes as compared to fullerene-based compounds. Five new non-fullerene donor molecules were designed keeping in view the excellent donor properties of 3-bis(4-(2-ethylhexyl)-thiophen-2-yl)-5,7-bis(2ethylhexyl) benzo[1,2-:4,5-c′]-dithiophene-4,8-dione thiophene-alkoxy benzene-thiophene indenedione (BDD-IN) by end-capped modifications. Photovoltaic and electronic characteristics of studied molecules were determined by employing density functional theory (DFT) and time dependent density functional theory (TD-DFT). Subsequently, obtained results were compared with the reference molecule BDD-IN. The designed molecules presented lower energy difference (ΔΕ) in the range of 2.17–2.39 eV in comparison to BDD-IN (= 2.72 eV). Moreover, insight from the frontier molecular orbital (FMO) analysis disclosed that central acceptors are responsible for the charge transformation. The designed molecules were found with higher λmax values and lower transition energies than BDD-IN molecule due to stronger end-capped acceptors. Open circuit voltage (Voc) was observed in the higher range (1.54–1.78 V) in accordance with HOMOdonor–LUMOPC61BM by designed compounds when compared with BDD-IN (1.28 V). Similarly, lower reorganization energy values were exhibited by the designed compounds in the range of λe(0.00285–0.00370 Eh) and λh(0.00847–0.00802 Eh) than BDD-IN [λe(0.00700 Eh) and λh(0.00889 Eh)]. These measurements show that the designed compounds are promising candidates for incorporation into solar cell devices, which would benefit from better hole and electron mobility. [ABSTRACT FROM AUTHOR]

The global need for renewable sources of energy has compelled researchers to explore new sources and improve the efficiency of the existing technologies. Solar energy is considered to be one of the best options to resolve climate and energy crises because of its long-term stability and pollution free energy production. Herein, we have synthesized a small acceptor compound (TPDR) and have utilized for rational designing of non-fullerene chromophores (TPD1–TPD6) using end-capped manipulation in A2–A1–D–A1–A2 configuration. The quantum chemical study (DFT/TD-DFT) was used to characterize the effect of end group redistribution through frontier molecular orbital (FMO), optical absorption, reorganization energy, open circuit voltage (Voc), photovoltaic properties and intermolecular charge transfer for the designed compounds. FMO data exhibited that TPD5 had the least ΔE (1.71 eV) with highest maximum absorption (λmax) among all compounds due to the four cyano groups as the end-capped acceptor moieties. The reorganization energies of TPD1–TPD6 hinted at credible electron transportation due to the lower values of λe than λh. Furthermore, open circuit voltage (Voc) values showed similar amplitude for all compounds including parent chromophore, except TPD4 and TPD5 compounds. These designed compounds with unique end group acceptors have the potential to be used as novel fabrication materials for energy devices. [ABSTRACT FROM AUTHOR]

End‐capped acceptors modification of fused ring electron acceptors (FREAs) is an attractive strategy to boost the optoelectronic and photovoltaic properties of the materials. FREAs are also proven beneficial due to their tremendous applications in organic solar cells (OSCs). Among fused‐ring electronic species, small fullerene‐free FREAs have already been drawn more attention due to their near‐infrared sensitivity and constantly increasing efficiencies. Therefore, we have designed six new FREAs (K1–K6) having selenophene as π‐bridge in between the central alkylated indaceno[1,2‐b:5,6b]dithiophene (IDT) unit after the incorporations of various end‐capped acceptors on to the recently synthesized IDT2SeC2C4‐4F molecule. Structural–property relationship and photophysical and photovoltaic properties of newly designed molecules are studied with the help of density functional theory (DFT) and time‐dependent DFT (TD‐DFT). Certain critical specifications like frontier molecular orbitals (FMOs) alignment, density of states (DOS), absorption maxima, excitation energy, binding energy (BE) along with transition density matrix (TDM), and the specifically estimated reorganizational energy values of electron and hole and the open circuit voltages of newly designed molecules are computed and compared with reference molecule. Generally, a red‐shifting absorption behavior of FREAs is considered the most important reason for their high efficiencies in OSCs. Our novel designed molecules exhibit red shift in absorption spectrum. Similarly, low excitation and binding energies of designed molecules offer improved power conversion efficiencies (PCEs) with highest possible charge photocurrent density (Jsc) in OSCs devices. Furthermore, study of PTB7‐Th/K1 complex is also done in order to examine charge transfer between within complex. By introducing the efficient end‐capped acceptor moieties in reference molecule, enhancement in charge mobilities is noted. The large open circuit voltage, low reorganizational energies, narrower highest occupied molecular orbital–lowest unoccupied molecular orbital (HOMO–LUMO) energy gap, lower binding and excitation energies, and highly red shifting in absorption phenomenon indicate an efficient designing of molecules, which could be best fitted for high efficiency OSCs. Finally, theorized molecules are much superior related to their photovoltaic and electronic properties and thus are recommended to experimentalist for their synthesis and out‐looking future developments of highly efficient solar cells devices. [ABSTRACT FROM AUTHOR]

Hole transport materials (HTMs), especially dopant-free hole transport materials, are getting attention in enhancing the power conversion efficiencies and stabilities of organic solar cells (OSCs). Herein, we have designed efficient dopant-free HTMs (DM1–DM5) from an outstanding synthetic DFM molecule (having 20.6% PCE). Photo-physical, photovoltaic, optoelectronic and structural-property relationship of newly designed molecules are extensively studied and compared with DFM (R). Density functional theory (DFT) and time-dependent-density functional theory (TD-DFT) have been employed to investigate the alignment of frontier molecular orbitals (FMOs), optical properties, density of states along with transition density matrix, binding and excitation energy, reorganizational energies and for open-circuit voltages of all newly designed molecules. Red-shifting in absorption spectrum offers high power conversion efficiencies, and our tailored molecules exhibit red-shifting in absorption spectrum (λmax = 391–429 nm) as compared to R (λmax = 396 nm). In addition, our all designed molecules expressed better hole transport ability (λh = 0.0056–0.0089 eV) as compared to R (λh = 0.0101 eV). Similarly, DM1–DM5 disclosed narrow HOMO–LUMO energy gap which causes maximum charge transfer from excited HOMO to excited LUMO. The theoretical study of DM3/PC61BM and DM3/Y6 complexes is also performed in order to understand the shifting of charge between donor and acceptor molecules. Results of all analysis clearly show the efficient designing of dopant-free (DM1–DM5) molecules and their possible potential to fabricate a high performance and stable organic solar cells devices. Therefore, the theoretical proposed molecules are recommended to experimentalists for future highly efficient organic solar cells. [ABSTRACT FROM AUTHOR]

End‐capped modification is a convenient strategy to enhance the photovoltaic and electronic properties of fullerene‐free acceptor materials. In this report, five novel star‐shaped three‐dimensional acceptor molecules FH1–FH5 are designed by end‐capped modifications of recently synthesized star‐shaped Tr (Hex)6‐3BR molecule. The enhancement in the photovoltaic, electronic, and photophysical properties of designed molecules is examined with the aid of density functional theory (DFT) and time‐dependent DFT (TDDFT). The MPW1PW91 functional in conjunction with 6‐31G(d,p) basis set of DFT/TDDFT is employed in order to compute various key parameters including frontier molecular orbitals analysis, absorption maxima, and binding energy along with transition density matrix, open‐circuit voltage, excitation energy, charge mobilities (electron and hole reorganizational energies), density of states, charge transfer with respect to HOMOPTB7‐Th–LUMOacceptor, and dipole moment. Red shifting in absorption spectra of acceptor materials is the most important reason for increasing efficiency of organic solar cells. A red shift in absorption spectra of all designed molecules is noted with low excitation energy. Designed molecules FH1–FH5 exhibit narrow energy gap with high electron mobility as compared with Tr (Hex)6‐3BR molecule. Among all designed molecules, FH4 is proved to be the best candidate for fullerene free organic solar cells because of narrow band gap, high charge mobility, high dipole moment, low excitation, and binding energy along with a red shift in absorption spectrum. Moreover, all designed molecules offer high current charge density as compared with Tr (Hex)6‐3BR. These results indicate that all star‐shaped conceptual molecules (FH1–FH5) are ideal aspirants for construction of future organic solar cells. Highlights: Five novel star‐shaped three‐dimensional acceptor molecules FH1–FH5 are designed by end‐capped modifications of recently synthesized star‐shaped Tr (Hex)6‐3BR molecule.The enhancement in the photovoltaic, electronic, and photophysical properties of FH1–FH5 is examined through density functional theory and time‐dependent density functional theory.Designed molecules FH1–FH5 exhibit narrow energy gap and better photovoltaic properties with high electron mobility as compared with Tr (Hex)6‐3BR molecule.All star‐shaped conceptual molecules (FH1–FH5) are ideal molecules for construction of future organic solar cells. [ABSTRACT FROM AUTHOR]

Herein, we have designed four small molecular donors (SMDs) with Donor–Acceptor–Acceptor (D–Á–A) backbone having different acceptor units for highly efficient organic solar cells (OSCs). The specific molecular modeling has been made by replacing the additional acceptor unit (A) of recently synthesized TPA-DAA-MDN molecule (R) by employing different highly efficient acceptor units in order to improve the photovoltaic performances of the molecules. A theoretical approach (DFT and TD-DFT) has been applied to investigate the photophysical, opto-electronic and photovoltaic parameters of the designed molecules (DAA1–DAA4) and compared with the reference molecule (R). The red-shifting absorption of SMDs is the most important factor for highly efficient OSCs. Our all formulated molecules showed a red shifted absorption spectrum and also exhibit near IR sensitivity. Acceptor unit modification of R molecule causes reduction in HOMO-LUMO energy gap; therefore, all designed molecules offer better opto-electronic properties as compared to R molecule. A variety of certain critical factors essential for efficient SMDs like frontier molecular orbitals (FMOs), absorption maxima, dipole moment, exciton binding energy along with transition density matrix, excitation energy, open circuit voltages and charge mobilities of (DAA1–DAA4) and R have also been investigated. Generally, low values of reorganizational energy (hole and electron) offer high charge mobility and our all designed molecules are enriched in this aspect. High open circuit voltage values, low excitation energies, large dipole moment values indicate that our designed SMDs are suitable candidates for high-efficiency OSCs. Furthermore, conceptualized molecules are superior and thus are suggested to experimentalist for out-looking future progresses of highly efficient OSCs devices. Herein, four D-A-Á backbone based SMDs are designed and studied with aid of advances quantum chemical techniques. All calculations have been performed at MPW1PW91/6-31G(d,p) basis set. The computed results of all analysis suggest that our designed SMDs have better photovoltaic, opto-electronic and photo-physical properties as compared to R molecule. [ABSTRACT FROM AUTHOR]

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, open‐circuit 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The construction of environmentally friendly organic solar cells (EFOSCs) is an emerging field of research. The OSCs constructed from famous end-capped acceptors 2-(6-oxo-5,6-dihydro-4H-cyclopenta [ c ]thiophen-4-ylidene)malononitrile (TC) and 1,1-dicyanomethylene-3-indanone (IC) are exhibiting high efficiencies. However, IC and TC are cyanides (−C N), and their synthesis is harmful to the environment. Reports demonstrated that replacing the toxic (−C N) with non-toxic (-CF 3 , –SO 3 H, –NO 2) is an expedient strategy for designing EFOSCs. Using reported strategy, nine carbazole-thiophene-based compounds (DTC1-DTC9) are proposed to make EFOSCs. Photovoltaic and optoelectronic potential of DTC1-DTC9 is confirmed through FMO, DOS, TDM, reorganization energy of the electron (λ e), hole (λ h), transport rate of electron (t electron) and hole (t hole), exciton-binding energy (E b), transition energy (E x), open-circuit voltage (V oc), charge transfer with respect to PTB7-Th donor :DTC Acceptor complex and electron excitation analysis using DFT and TDDFT computations. The lower HOMO-LUMO gap (2.16 eV), E x (1.81 eV), strong λ max intensity (686.17 nm), high V oc (1.85 V) and weak exciton-binding energy (0.14 eV) of DTC1-DTC9 than reference DTC specified that they have potential to absorb more solar energy and excitons are easier to separate into free charges. Charge transfer analysis proved the charge transfer from HOMO PTB7-Th to LUMO DTC-3 in PTB7-Th:DTC-3 blend. Consequently, proposed carbazole-thiophene-based novel compounds (DTC1-DTC9) are recommended for making EFOSCs with promising photovoltaic properties. This work can provide a new –C N free molecular design viewpoint in computational and experimental sciences for constructing high-performance environmental friendly OSCs. [ABSTRACT FROM AUTHOR]

Making contribution to the development of novel photovoltaic materials for solar cell applications, we rationally developed six novel vinylbenzene based planar donor-π-acceptor (D-π-A) compounds. Optoelectronic properties of developed molecules are determined using frontier molecular orbital (FMO), UV–Visible, density of state (DOS), transition density matrix (TDM) heat map, open circuit voltage (Voc), binding energies (E b), reorganization energy of electron (λ e), hole (λ h), charge transfer analysis and compared with reference DVB-T-ID. Donor group modifications effectively contributed to augment photovoltaic features in all developed compounds. Developed molecules are found with reduced energy gap (2.566–1.805 eV), broaden absorption wavelength (548.09–800.36 nm) and small transition energy (2.262–1.549 eV) as compared to reference DVB-T-ID values 2.819 eV, 492.84 nm and 2.515 eV respectively. The developed molecules have proficient hole and electron transfer mobilities and can serve as best candidate when blended with PC 61 BM film. Optoelectronic features of all developed molecules especially D5 is ascertained eye-catching as compared to DVB-T-ID , hence recommended for future solar cell applications. [Display omitted] • Six vinylbenzene based planar D-π-A photovoltaic compounds are designed by donor group modifications. • The optoelectronic properties were studied in detail using DFT and TDDFT calculations. • FMO, UV–Visible, DOS, ODOS, TDM, Voc, reorganization energy of electron and hole, binding energy and charge transfer analysis are performed. • All vinylbenzene based investigated molecules exhibited remarkable optoelectronic properties. • Investigated molecules are recommended for future solar cell applications. [ABSTRACT FROM AUTHOR]

The air conditioning in hot and arid climates remains one of the grand challenges for food production in greenhouses. Therefore, significant efforts are given to determine the suitable techniques for effective cooling of greenhouses. Usually, greenhouses are used in colder climates to gather sunlight for heating purposes. However, hot climates with elevated solar irradiation characteristics suffer from high temperatures within the greenhouse. In this study, we propose a unique method solving the extensive cooling requirement of greenhouses in hot arid climates by employing an optimal spectra management strategy. The novel sun-tracking roof design of the greenhouse incorporates hot dielectric mirrors and solar panels, which help to reduce the cooling load and provide electricity to the vapor compression cooling unit. The spectrum above 750 nm is reflected to vertically aligned InGaAs solar cells for additional power generation, whereas the c-Si solar cells are able to provide effective shadowing at noontime without significant comprimise on photosynthetically active radiation (PAR) while producing power. The results showed an average reduction of 28.9% and 25.4% in the cooling load of the proposed greenhouse compared to the conventional greenhouse during the summer and winter seasons for sun tracking hours (10:00 a.m. to 1:00 p.m.), respectively, at a set greenhouse temperature of 28 °C. The proposed greenhouse produced an average of 22.18 kWh/day of electrical energy throughout the year. The novel roof significantly lowers the cooling load and partially meets the energy demand of greenhouses without compromising on photosynthetically active radiations to enter the greenhouse. • Proposed a novel greenhouse roof integrating hot mirrors and solar PVs for optimal spectra management. • The infrared spectrum is not allowed to enter the greenhouse and utilized by InGaAs PVs. • Proposed greenhouse has significant lower cooling load than conventional greenhouse. • Proposed greenhouse is optimally designed for self-sufficient greenhouses in hot arid climates. [ABSTRACT FROM AUTHOR]

• DFT and TDDFT calculations were performed on N -phenylaniline-triazol configured donor materials for efficient solar cells. • Six donor photovoltaic molecules (T1-T6) were designed by changing acceptor moieties of renowned synthesized TAZ-[MeOTPA] 2 molecule. • The electronic, optical and photovoltaic properties were studied in detail. • The FMOs, DOS graphs, reorganization energies, open circuit voltage, TDM surfaces and charge transfer characteristics were evaluated. • The studied compounds are proposed to be better entrants for organic solar cell applications. • This work may provide useful means in designing of new photovoltaic compounds. Considering the significant role of photovoltaic materials in diverse optoelectronic applications, N -phenylaniline-based six new donor molecules (T1-T6) are quantum chemically explored herein. Various parameters like frontier molecular orbital (FMO), density of states (DOS), transition density matrix (TDM) analysis, absorption maxima, reorganization energies of electron and hole, open circuit voltage (V oc), photophysical characteristics and charge transfer analysis have been estimated in order to understand the performance of newly designed molecules. End caped acceptors modification causes narrowing of HOMO-LUMO energy gap (2.99–3.33 eV) as compared to R (4.04 eV). All designed molecules exhibited absorption spectrum in the range of 334–370 nm in solvent phase and 324–403 nm in gas phase. T1-T6 show maximum charge transfer from HOMO to LUMO orbital which plays a key role in conductive materials. Dipole moment value of designed molecules in ground and excited states are found to be larger than reference molecule which suggested that our designed molecules have more solubility in organic solvent as compared to reference molecule. All designed molecules show better reorganizational energy of electron (0.0191–0.0273 E h) and hole (0.0063–0.0187E h). Among designed molecules T3 has lowest reorganizational energy of electron which means that it has highest charge mobility. The V oc with respect to HOMO donor -LUMO PC61BM shows that designed molecules [ T1-T6 (V oc = 1.08–1.50 V)] have better V oc as compared to R (V oc = 0.73 V). This theoretical framework proves that conceptualized molecules are superior and thus are recommended for the future construction of high performance organic solar cells. [ABSTRACT FROM AUTHOR]

• Five non-fullerene organic molecules are designed from the BTP-Cl molecule. • The newly designed molecules have better photovoltaic parameters (such as charge mobility) due to the introduction of highly efficient acceptor moieties. • The entitled molecules exhibited better absorption coefficient in chloroform solvent as compared to the previously reported BTP-Cl molecule. • Efficient acceptor groups decreases about 10 times the band gap energy as compared to chlorine-based BTP-Cl molecule. To enhance the efficiency of organic solar cells (OSCs), five non-fullerene π-conjugated acceptor molecules namely BTM1 , BTM2 , BTM3 , BTM4 and BTM5 are designed from recently reported 16.5% efficient acceptor molecule BTP-Cl. The molecules in the present quantum chemical investigation consist of benzothiazole (BT) core with different chemical species on the terminal side. The optoelectronic study of BTM1-BTM5 reveals that BTM3 and BTM4 molecules are superior with respect to absorption range found at the wavelengths of 780 and 791 nm as compared to 746 nm of reference molecule BTP-Cl. Frontier molecular orbital (FMO) and transition density matrix (TDM) analysis are performed that give basic information about the distribution of charges among investigated molecules. All investigated molecules exhibit charge density spread over the entire molecules. The BTM4 and BTM5 molecules efficiently transfer their electron densities from highest occupied molecular orbital (HOMO) to lowest unoccupied molecular orbital (LUMO) with narrow bandgaps of 1.86 eV and 2.14 eV respectively. The electron mobility for BTM3 (0.00527), BTM4 (0.005820) and BTM5 (0.00539) are found less than BTP-Cl (0.00643). Similarly, BTM5 gives the least value of hole mobility (0.00558) as compared to BTP-Cl (0.00803). The binding energies of these molecules are also observed less (0.28 eV, 0.29 eV and 0.33 eV for BTM3 , BTM4 and BTM5) in gas phase than BTP-Cl (0.35 eV). Also, BTM5 is tested with donor polymer PTB7-Th that provides further evidence for their interactions. It turned out that the structural tailoring at terminals can tune effectively the frontier molecular orbital energy levels, band gap, absorption spectra, open-circuit voltage, reorganization energy and binding energy value in investigated molecules. Our results suggest that the investigated molecules can serve as fine acceptor materials. Additionally, some investigated molecules can also be used as a hole and/or electron transport materials for OSCs. [ABSTRACT FROM AUTHOR]

Here, we computed the Y1-Y4 acceptors by end-capped alterations on reference R to optimize photophysical, optoelectronic, and photovoltaic properties. Herefore, certain properties such as the orientation of FMO's, excitation and binding energy, open-circuit voltage, transition density matrix, and reorganizational energy of electron and hole are also observed and associated with the reference. The Y1 and Y4 calculated molecular structures showed a high red-shifting while Y2 and Y3 slightly blue-shifting, very fine excitation energies and high charge mobilities. All these molecules (Y1-Y4) and the reference R display band-gaps as small as 1.5–2.5 eV, and considerable charge-shifting potential. This theoretical system shows that end-capped acceptors alteration is quite remarkable to establish desired optoelectronic properties. [Display omitted] • Efficient electron acceptor materials (Y1-Y4) have been designed to produce highly efficient solar cell devices. • The structural–property relationship, photovoltaic and opto-electronic properties of designed molecules were investigated and compared with reference R. • All designed molecules displayed remarkable binding energy values, fine excitation energies, better open-circuit voltage, and high charge mobilities than R. • All designed molecules show that end-capped acceptors alteration is remarkable to establish desired optoelectronic properties. Non-fullerene organic solar cells (OSCs) deliver the highest efficiency gains overall in reported literature. Efforts are being made to refine efficacies and stabilities of organic solar cells through the designing of acceptor molecules that contain powerful electron-withdrawing groups. Here, we computed four acceptors (Y1-Y4) by end-capped alterations on reference R and optimize photophysical, optoelectronic and photovoltaic properties. Therefore, certain properties such as orientation of FMO's, excitation and binding energy, open-circuit voltage (V oc), transition density matrix and reorganizational energy of hole and electron are observed in comparison with reference. The calculated molecular structures of Y1 and Y4 show a high red-shift, while that of Y2 and Y3 display slightly blue-shift, along with very fine excitation energies and high charge mobilities. All these molecules (Y1-Y4) and the reference R presents band-gaps as small as 1.5–2.5 eV, and considerable charge transfer potential. This theoretical system shows that end-capped acceptors alteration is quite remarkable to establish desired optoelectronic properties. Thus, Y1-Y4 are suggested to researchers aiming at the potential commercialization of highly efficient solar cells systems. [ABSTRACT FROM AUTHOR]

Chrysene core containing fused ring acceptor materials have remarkable efficiency for high performance organic solar cells. Therefore, present study has been carried out with the aim to design chrysene based novel Z -shaped electron acceptor molecules (Z1-Z6) from famous Z-shaped photovoltaic material FCIC (R) for organic photovoltaic applications. End-capped engineering at two electron-accepting end groups 1,1-dicyanomethylene-3-indanone of FCIC is made with highly efficient end-capped acceptor moieties and impact of end-capped modifications on structure-property relationship, photovoltaic and electronic properties of newly designed molecules (Z1-Z6) has been studied in detail through DFT and TDDFT calculations. The efficiencies of the designed molecules are evaluated through energy gaps, exciton binding energy along with transition density matrix (TDM) analysis, reorganizational energy of electron and hole, absorption maxima and open circuit voltage of investigated molecules. The designed molecules exhibit red-shift and intense absorption in near-infrared region (683–749 nm) of UV–Vis-NIR absorption spectrum with narrowing of HOMO-LUMO energy gap from 2.31 eV in R to 1.95 in eV in Z5. Moreover, reduction in reorganization energy of electron from 0.0071 (R) to 0.0049 (Z5), and enhancement in open circuit voltage from 1.08 V in R to 1.20 V in Z5 are also observed. Twisted Z -shape of designed molecules prevents self-aggregation that facilitates miscibility of donor and acceptor. Low values of binding energy, excitation energy, and reorganizational energy (electron and hole) suggest that novel designed molecules offer high charge mobilities as compared to FCIC. Our findings indicate that these novel designed molecules can display better photovoltaic parameters and are suitable candidates if used in organic solar cells. Unlabelled Image • Novel Z-shaped fused chrysene acceptors (Z1-Z6) were studied for organic solar cells. • Electronic, photophysical and photovoltaic properties were explored. • Studied acceptor molecules have remarkable optoelectronic properties as compared to reference R • Studied molecules are recommended for high performance organic solar cells. [ABSTRACT FROM AUTHOR]

Nowadays, organic solar cells (OSCs) with non-fullerene electron acceptors provide the highest efficiencies among all studied OSCs. To further improve the efficiencies of fullerene-free organic solar cells, end-capped acceptor modification is made with strong electron withdrawing groups. In this report, we have theoretically designed five new novel Benzodithiophene core-based acceptor molecules (H1-H5) with the aim to study the possible enhancement in photophysical, optoelectronic, and photovoltaic properties of newly designed molecules. The end-capped acceptor modification of famous and recently synthesized FBDIC molecule has been made with strong electron withdrawing groups. Density functional theory and time-dependent-density functional theory are extensively used to study the structural-property relationship, optical properties and various geometrical parameters like frontier molecular orbitals alignment, excitation and binding energy, transition density matrix along with open circuit voltage, density of states and dipole moment. Commonly, low reorganization energies (hole and electron) afford high charge mobility and our all designed systems are enriched in aspect (λ e = 0.0044–0.0104 eV and λ h = 0.0060–0.0090 eV). Moreover, H1-H5 molecules demonstrate red-shifting in absorption spectrum (λ max = 741–812 nm) as compare to R (λ max = 728 nm). Low excitation and binding energies with low HOMO (highest occupied molecular orbital)-LUMO (lowest unoccupied molecular orbital) energy gap of H1-H5 suggested that designed molecules are better and suitable candidates for high performance organic solar cell. Results of all analysis indicate that this theoretical framework demonstrates that end-capped acceptors modification is a simple and effective alternative strategy to achieve the desirable optoelectronic properties. Therefore, H1-H5 are recommended to experimentalist for out-looking future developments of highly efficient solar cells. Unlabelled Image • Five new acceptor materials having benzodithiophene core are designed for organic solar cells. • The structure–property relationship, and photovoltaic properties of designed molecules is studied. • All newly designed molecules have excellent opto-electronic properties with respect to reference compound. [ABSTRACT FROM AUTHOR]

Non fullerene small acceptor molecules in organic photovoltaics are proven beneficial than the traditional fullerene based acceptors for their fine contribution in organic solar cells. Researchers are constantly doing efforts for designing novel acceptor materials with promising photovoltaic properties. Designing of novel molecules by end-capped modifications is a convenient strategy to obtain high efficiency acceptor molecules for OSCs. Herein, we studied optoelectronic characteristics of five novel acceptor–donor–core–donor–acceptor configured small acceptor molecules (S1–S5) after end-capped modifications of recently synthesized DF-PCIC molecule. Designed molecules S1–S5 consist of 1,4-difluorobenzene (as central core), 4,4-bis(2-ethylhexyl)-2,6-dimethyl-4H-cyclopenta[1,2-b:5,4-b′]dithiophene as donor which directly attached with different end-capped acceptors. The electronic and optical properties of newly designed (S1–S5) molecules are examined and compared with reference molecule with the aid of DFT and TD-DFT. Certain key parameters like frontier molecular orbitals analysis, density of states, dipole moment, binding energy along with transition density matrix, excitation energy, charge mobility, absorption maxima and charge transfer analysis have been performed in order to explore the photo-physical, optoelectronic and photovoltaic properties of designed and reference molecule. Out of newly designed structures, S4 displayed lowest energy band-gap (2.25 eV) with red-shifting in absorption spectrum (λmax = 712.43 nm) in chloroform which disclosed the perfect relationship between end-capped acceptor with large electron withdrawing character through extended conjugation. Similarly, S1 exhibited highest value (1.53 V) of open circuit voltage (Voc) with respect to PTB7-Th donor material owing to lower values of λe. Designed molecules exhibit better electron and hole mobility as compared to reference molecule R. All molecules express better absorption maximum, open circuit voltage, low excitation energies, comparable binding energies, large dipole moment and efficient electron and hole transport as compared to reference molecules. So, results these parameters suggest that end-capped modification is a convenient strategy in order to enhance the efficiency of OSCs. Therefore, conceptualized molecules are recommended to experimentalist for out-looking future developments of highly efficient solar cells. [ABSTRACT FROM AUTHOR]

The modification of end-capped acceptors of a molecule is an efficient strategy for novel solar cells. In this line, we have tailored and explored eight novel molecules for possible application in photovoltaics. Further, a neat and clean light absorption spectrum has been recorded for designed molecules (T1-T8) in the organic solvent. The lower values of excitation energy of novel molecules help in easy excitation and dissociation of excitation in the excited state. Moreover, the mobility in the active layer of electron and hole of solar cell is high, which is seen in T1 to T8 molecules. Overall, the geometric and physiochemical analysis highlights the high performance of tailored molecules of solar cells. The density functional theory (DFT) calculations were used to estimate FMO analysis, Electrostatic-Potential (ESP), Density of States (DOS) graphs, Reorganizational Energy, photovoltaic properties, and charge transmission investigation. Engineered particles have greater and identical optoelectronic properties than synthetic reference molecules. T5 has emerged as the best candidate among all the molecules studied because of its talented photovoltaic properties, which contain the minimum bandgap (1.99 eV), the mobility of electrons, and hole are (λ e = 0.0112 eV), (λ h = 0.0101 eV), respectively. These materials showed a lower binding energy (E b = 0.48 eV), and are highly red-shifted in absorption spectrum i.e. 798.55 nm (in gas), while 820.49 nm in chloroform. Moreover, these materials also presented a good value of Open circuit voltage (V oc), which are in the range of 1.26–1.83 V for the designed series (T1-T8), while 1.77 V for the R molecule. Therefore, we highly suggest these materials for the future development of an efficient organic solar cells (OSCs). [ABSTRACT FROM AUTHOR]

Recently, the scientific community has shown great interest in hole transport materials (HTMs) to develop efficient and stable organic and perovskite solar cells. To boost the photovoltaic performance of these solar cell devices, scientists have been investigating the use of modified HTMs. In this study, we have developed a distinctive and proficient approach to building a better photovoltaic material by modifying the endcaps of the reference (MA). Specifically, we designed five new efficient HTMs (MA1-MA5) through molecular engineering on a terminal of reference molecule MA. Using density functional theory (DFT) and time-dependent-DFT methods, we theoretically characterized the key characteristics of these newly designed materials, including the orientation of frontier molecular orbitals (FMO), absorption maxima, the partial density of states (PDOS), binding energies, reorganization energy, transition density matrix, fill factor (FF), open-circuit voltages (V oc) and power conversion efficiencies (PCEs) for these materials. Our theoretical representations revealed that newly constructed materials (MA1-MA5) have a highly red-shifted absorption spectrum with lower binding energies and narrow energy gaps, making them ideal for charge shifting. Among these designed MA1-MA5 materials, the MA1 has the potential to produce as much as higher 23.24% PCE when it will be used in fabricating solar cell devices, whereas, the other designed materials MA2-MA4 has also very comparable and much higher PCE values than the refence molecule MA. These findings demonstrate our efficient designing approach to tune the photovoltaic and optoelectronic properties of the HTMs, and we recommend these engineered materials for the future developments of an efficient solar cell devices. Recently, the scientific community has shown great interest in hole transport materials to develop efficient organic and perovskite solar cells. Therefore, we have developed a distinctive and proficient approach to building a better photovoltaic material by modifying the endcaps of the reference (MA). Our efficient designing and theoretical characterization approach are helpful to tune the photovoltaic and optoelectronic properties of photovoltaic materials, and we can thus, recommend these engineered materials for the future developments of an efficient solar cell devices. [Display omitted] • A series of new hole transporting materials (MA1-MA5) are designed for optoelectronic devices. • A narrower energy gaps and improved absorption characteristics are seen. • These hole transporting materials (MA1-MA5) displayed an excellent electron/hole reorganization energy. • These hole transporting materials (MA1-MA5) offered enhanced optoelectronic characteristics in-contrast to reference R. [ABSTRACT FROM AUTHOR]

Tilde-shaped materials based on pyrrolo [3,2- b ]pyrrole (PP) have attracted a lot of interest as potential acceptors for organic solar cells (OSCs) because of their wide range of energy levels, high absorption efficiency, and three-dimensional (3D) charge transport properties. Herein, we have effectively developed and characterized tilde-shaped PPIC-based acceptor materials (RK1-RK7) using PP as the central-core unit to probe their optical and optoelectronic characteristics. These engineered tilde-shaped (RK1-RK7) materials displayed deeper HOMO levels and more significant extinction coefficients, likely to provide improved phase separation morphology while blend formation. The complete theoretical characterization of these molecules (RK1-RK7) and reference (R) has been achieved using advanced quantum chemical approaches. In addition, density functional theory (DFT) and time-dependent (TD-DFT) simulations have explored the photophysical and optoelectronic properties. Optical properties, frontier molecular orbital (FMO), light harvesting efficiency (LHE), the density of states (DOS), open-circuit voltages, reorganization energy of holes and electrons, and transition density matrix (TDM) have all been studied in these substances. RK4 has an absorption maximum (λ max) at 783.47 nm and an optical band gap minimum of 0.87 eV. The mechanism of extraordinary charge shifting at the donor-acceptor interface was also revealed by a detailed investigation of RK4/PTB7-Th. Our proposed approach is the key backbone to construct efficient molecules for OSCs. Graphical abstract: We have effectively developed and characterized tilde-shaped PPIC-based acceptor materials (RK1-RK7) using PP as the central-core unit to probe their optical and optoelectronic characteristics. These engineered tilde-shaped (RK1-RK7) materials displayed deeper HOMO levels and more significant extinction coefficients, likely to provide improved phase separation morphology while blend formation. [Display omitted] • Tilde-shaped acceptors (RK1-RK7) are designed for organic solar cells. • Improved and near-infrared absorption and narrower bandgaps are observed. • These tilde-shaped (RK1-RK7) presented a good electron/hole reorganizational energy. • These molecules (RK1-RK7) displayed enhanced optoelectronic characteristics as compared with reference R. [ABSTRACT FROM AUTHOR]

The development of small molecule-based (SMs) organic photovoltaic (PV) materials is under intense attention by the researchers for organic solar cells (OSCs) to constantly revise their power conversion efficiencies (PCEs). Therefore, we have designed a series of Z-shaped non-fullerene acceptors (NFAs) (SNAA1-SNAA6), and characterized them theoretically for the possible use of in efficient OSCs devices. We have designed this Z-shaped series after employing several end-capped modifications over reference molecule (COi5DFIC (R)) to enhance their photovoltaic parameters further. We have extensively characterized these Z-shaped NFAs and explored their optoelectronic, photovoltaic and structure-property relationship with density functional theory (DFT) and time-dependent (TD-DFT). As a result, this Z-shaped NFA series (SNAA1-SNAA6) showed attractive narrower bandgaps (E g) compared to parent molecule R, and all are extremely red-shifted in the UV-Visible absorption spectrum. Moreover, we have also performed a complex study of donor:acceptor (D:A) blend (SNAA1:PTB7-Th) to show their compatibility in fabricating highly efficient OSCs devices. • Z-Shaped Non-fullerene acceptors (SNAA1-SNAA6) are designed for organic solar cells. • Highly red-shifted absorption, and an attractive narrow band-gaps are observed. • The non-fullerene acceptors showed an outstanding electron/hole reorganizational energy. • The designed materials (SNAA1-SNAA6) exhibited better optoelectronic properties as compared with reference R. [ABSTRACT FROM AUTHOR]