Zobia Irshad

Bio: Zobia Irshad is an academic researcher from Chosun University. The author has contributed to research in topics: Organic solar cell & Acceptor. The author has an hindex of 12, co-authored 23 publications receiving 319 citations.

Efficient designing of triphenylamine-based hole transport materials with outstanding photovoltaic characteristics for organic solar cells

Abstract: 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.

Designing of near-infrared sensitive asymmetric small molecular donors for high-efficiency organic solar cells

Abstract: Herein, we have designed four small molecular donors (SMDs) with Donor–Acceptor–Acceptor (D–A–A) backbone having different acceptor units for highly efficient organic solar cells (OSCs). The specif...

Revisiting the role of renewable and non-renewable energy consumption on Turkey’s ecological footprint: Evidence from Quantile ARDL approach

Abstract: The current study re-investigates the impact of renewable and non-renewable energy consumption on Turkey’s ecological footprint. This study applies Quantile Autoregressive Lagged (QARDL) approach for the period of 1965Q1-2017Q4. We further apply Granger-causality in Quantiles to check the causal relationship among the variables. The results of QARDL show that error correction parameter is statistically significant with the expected negative sign for all quantiles which confirm an existence of significant reversion to the long-term equilibrium connection between the related variables and ecological footprint in Turkey. In particular, the outcomes suggested that renewable energy decrease ecological footprint in long-run on each quantile. However, the results of economic growth and non-renewable energy impact positively to ecological footprint in long-short run period at all quantiles. Finally, we tested the Environmental Kuznets Curve (EKC) hypothesis and the results of QARDL confirmed the EKC in Turkey. Furthermore, the findings of causal investigation from Granger-causality in quantiles evident the presence of a bi-directional causal relationship between renewable energy consumption, energy consumption and economic growth with ecological footprint in the Turkish economy.

How Does Bridging Core Modification Alter the Photovoltaic Characteristics of Triphenylamine-Based Hole Transport Materials? Theoretical Understanding and Prediction

Abstract: Perovskite solar cells have gained immense interest from researchers owing to their good photophysical properties, low-cost production, and high power conversion efficiencies. Hole transport materials (HTMs) play a dominant role in enhancing the power conversion efficiencies (PCEs) and long diffusion length of holes and electrons in perovskite solar cells. In hole transport materials, modification of π-linkers has proved to be an efficient approach for enhancing the overall PCE of perovskite solar cells. In this work, π-linker modification of a recently synthesized H-Bi molecule (R) is achieved with novel π-linkers. After structural modifications, ten novel HTMs (HB1-HB10) with a D-π-D backbone are obtained. The structure-property relationship, and optoelectronic and photovoltaic characteristics of these newly designed hole transport materials are examined comprehensively and compared with reference molecules. In addition, different geometric parameters are also examined with the assistance of density functional theory (DFT) and time-dependent DFT. All the designed molecules exhibit narrow HOMO-LUMO energy gaps (Eg =2.82-2.99 eV) compared with the R molecule (Eg =3.05 eV). The designed molecules express redshifting in their absorption spectra with low values of excitation energy, which in return offer high power conversion efficiencies. Further, density of states and molecular electrostatic potential analysis is performed to locate the different charge sites in the molecules. The reorganizational energies of holes and electrons are found to have good values, suggesting that these novel designed molecules are efficient hole transport materials for perovskite solar cells. In addition, the low binding energy values of the designed molecules (compared with R) offer high current charge density. Finally, complex study of HB9:PC61 BM is also undertaken to understand the charge transfer between the molecules of the complex. The results of all analyses advocate that these novel designed HTMs are promising candidates for the construction of future high-performance perovskite solar cells.

Efficient designing of triphenylamine-based hole transport materials with outstanding photovoltaic characteristics for organic solar cells

Abstract: 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.