Department of Chemistry

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Enhanced Hydrogen Storage and Dissociation on Metal Doped g-C3N4 via Electric Field Modulation: A DFT Study
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Syed Muhammad Zareef; CIIT/SP24-R06-023/LHR; Prof. Dr. Mazhar Amjad Gilani; LHR TP 10027
Hydrogen is a clean and sustainable energy source, yet its efficient storage and activation is still a challenge for sustainable energy solutions. This research provides theoretical study of late 3d transition metals (TM=Fe, Co, Ni, Cu, Zn) doped graphitic carbon nitride (TM@g-C3N4) systems using density functional theory with focus on adsorption and activation of hydrogen molecule. NBO charge analysis gives effective charge transfer between the transition metal centers and the g-C3N4 sheet. Frontier molecular orbital analysis and HOMO–LUMO gap provide enhanced electronic reactivity for all TM doped systems, while Co@g-C3N4 showing balance between reactivity and stability. Among all, Co@g-C3N4 has higher hydrogen adsorption with adsorption energy of -0.59 eV. The gravimetric hydrogen storage capacity of Co@g-C3N4 is up to 8.55 wt%, making it a suitable hydrogen storage material. Furthermore, the application of an external electric field modulated adsorption behavior, where positive fields increased adsorption energy, while negative fields decreased adsorption energy. Overall, this work establishes Co@g-C3N4 as an efficient single-atom catalyst and hydrogen storage material.
Transition Metal Doped B12N12 Nanocage as Single Atom Catalyst for Nitrogen Reduction to Ammonia: A DFT Study
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2026) Arshia Irfan; CIIT/SP24-R06-003/LHR; Prof. Dr. Mazhar Amjad Gilani; LHR TP 10015
Ammonia (NH3) is a crucial chemical used in fertilizer production and is now being recognized as a carbon-free hydrogen transporter for renewable energy applications. Despite its significance, the commercial synthesis of ammonia (NH3) relies primarily on the century-old Haber-Bosch process, which consumes large amounts of fossil fuels and contributes significantly to global CO2 emissions. As a result, establishing sustainable, low- energy routes for ammonia production under moderate settings has become a top research focus. The electrochemical nitrogen reduction reaction (eNNR) is a promising option, but its practical application is limited by slow N2 activation kinetics, low Faradaic efficiency, and competition with the hydrogen evolution reaction (HER). The TM-doped B12N12 nanocages as enhanced single atom catalyst (SACs) for effective electrochemical NH3 production are examined. In this study, density functional theory (DFT) simulations are performed to assess the structural integrity, thermodynamic stability, adsorption behavior, and electrical characteristics of different TM@B12N12 combinations. Interaction energy is calculated to investigate the stability of all transition metal doped boron nitride (B12N12) complexes, with the highest interaction energy observed for Ti@B12N12. Moreover, electronic analyses, such as Frontier Molecular Orbital (FMO), Natural Bond Orbital (NBO), Quantum Theory of Atoms in Molecules (QTAIM) and Molecular Electrostatic Potential (MEP), are used to investigate orbital interactions and to interpret shared or partially covalent interactions and charge transfer dynamics and bond characteristics during N2 adsorption and reduction. The adsorption of molecular nitrogen on the TM@B12N12 complexes exhibits negative adsorption energy, confirming the exothermic nature of N2 adsorption. Among the screened candidates, the Nickle-doped nanocage (Ni@B12N12) demonstrates outstanding catalytic performance, characterized by strong and favorable N2 adsorption, effective electron donation/ back-donation, and robust bonding properties, as proven by QTAIM parameters. The MEP and NBO investigations show a considerable charge distribution between active sites and N2 molecules, enhancing its activation. The prediction energy barrier for the potential-determining step (PDS) is 0.4258eV, indicating the catalyst’s thermodynamic feasibility for efficient ammonia synthesis. This study emphasizes that the TM@B12N12 complexes, i.e., Ni@B12N12 system, serves as a viable SAC platform for sustainable ammonia production. Atomic level insights guide the design of next generation of eNNR catalysts with higher selectivity and energy efficiency.
Fabrication & Characterization of Ti-Ce MOFs based silk electro spun membrane for bone Regeneration A combined DFT and Experimental Approach
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Tayyaba Fatima; CIIT/SP24-R06-027/LHR; Prof. Dr. Mazhar Amjad Gilani; LHR TP 10030
Neurosurgical procedures, traumatic brain injury, tumor resection, and cerebrovascular disorders may lead to leaking cerebrospinal fluid and development of severe complications such as infection, inflammation, and dysfunction of the nervous system. The traditional methods of dural repairs like sutures, sealants, and hydrogels are usually constrained by factors such as partial repair, immunogenic response, lack of accessibility and mechanical efficacy. In solving these issues, a mechanically stable, biocompatible and biodegradable scaffold should be developed. In this work we have fabricated a bilayer electrospun scaffold that was created using silk fibroin, calcium magnesium silicates (SILK+CMS), poly(epsilon-caprolactone) (PCL), with metal-organic frameworks (PCL+MOF) to regenerate the dura mater. The scaffolds were prepared and characterized in a systematic way by application of different techniques of analysis. The FTIR analysis showed that all components had characteristic functional groups, which correspond to the successful fabrication of the scaffolds. The bilayer scaffolds also had optimized hydrophilicity, swelling characteristics, porosity, and density that were beneficial in cell attachment, growth, diffusion of nutrients, and tissue integration. SEM examination demonstrated a consistent fibrous pattern and well organization of the fibers which were very similar to the normal dura mater structure. In vitro degradation tests proved that the scaffolds had a programmed rate of degradation that could be adjusted to the rate of healing in the dura mater. Moreover, in vitro biocompatibility tests revealed that there is a good cellular response, which indicates that the scaffold can facilitate cell attachment and viability. Altogether, the findings indicate that the developed bilayer scaffold can be regarded as the promising biomaterial candidate to repair dura mater, and it may help avoid the cerebrospinal fluid leakage and promote successful tissue regeneration

Department of Chemistry

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