Research
Research at the Spanopoulos Group focuses on utilizing molecular and crystal engineering for the design and synthesis of next-generation, environmentally stable, and friendly hybrid materials. These materials feature multiple functionalities, targeting applications such as photovoltaics, spintronics, sensing, gas separation, solid-state batteries, environmental remediation, anti-pathogen coatings, HAB mitigation, electro-catalysis, and photo-catalysis. The hybrid nature of the corresponding compounds is advantageous, combining both the merits of organic (e.g. tunable functionalization and mechanical properties) and inorganic constituents (e.g. semiconduction/magnetism) for the creation of novel structural and functional motifs.
Research Areas
Porous Metal Halide Semiconductors (PMHS)
1. A. Azmy, et al., Angew. Chem. Int. Ed. 2023, 62, e202218429 (Inside Cover + Team Profile)
2. A. Azmy, et al., ACS Appl. Mater. Interfaces 2023, 15, 42717
The generation of porosity to fully inorganic semiconductors enhanced their optoelectronic features and rendered them proper for uncharted applications, such as photocatalysis and energy storage.
Motivated by these attributes, we utilized molecular and crystal engineering to generate porosity to hybrid metal halide semiconductors (MHS) by using molecular cages serving as both structure-directing agents and counter-cations. Their presence not only rendered corresponding materials porous but also water-stable. Our work set the foundation for the development of a new family of materials, namely Porous Metal Halide Semiconductors (PMHS), offering fully customizable porosity and optoelectronic properties.
The porous nature and record water stability allow them to be utilized in various applications such as electro- and photocatalysis, sensing, photonic crystals, environmental remediation, and solid-state batteries, to name a few.
Crystalline Fullerene Metal Halide Semiconductors (FMHS)
1. W. Shen, A. Azmy, et al., Adv. Energy Mater. 2024, 2400582 (Front Cover )
We are motivated by the need to develop next-generation multifunctional Perovskite Solar Cell (PSC) interlayer materials in single-crystal form, that would allow the study and elucidation of structure-property relationships in a concrete way.
Towards this end, by means of molecular and crystal engineering, we designed and synthesized the first member of a new family of materials, namely Crystalline Fullerene-based Metal Halide Semiconductors (FMHS), (C60-2NH3)Pb2I6. The reduced dielectric confinement within the material’s sublayers and the compound’s high affinity for adjacent device layers (perovskite and C60) were expected to promote significant carrier transport. Apparently, its utilization as an interlayer in PSC improved both device performance and stability confirming our hypothesis.
We expect the new family of crystalline FMHS materials to offer opportunities beyond photovoltaics, to catalysis, transistors, and supercapacitors.
Multi-functional Hybrid Materials Against Pathogens
1. A. Azmy, et al., ACS Appl. Mater. Interfaces 2023, 15, 42717.
Antimicrobial Resistance (AMR) is identified by the World Health Organization (WHO) as one of the greatest threats humanity faces, and this problem is expected to deteriorate over the following decades. Next-generation antibacterial materials are greatly sought after since they offer multiple advantages compared to organic candidate molecules.
Taking a step further in material design, the presence of porosity coupled with water stability will allow corresponding materials to be utilized in applications beyond therapeutics, from water purification and disinfection, desalination, Harmful Algal Bloom mitigation, anti-fouling coatings, personal protective equipment (PPE) antibacterial coatings, antibacterial coatings in medical devices, to food packaging applications.
Considering the above, we target the development of multi-functional semiconductor materials of nontoxic composition, with fine-tunable porosity and permanent water stability, which are activated using visible light and exhibit anti-pathogen activity.
Chiral/Magnetic Semiconductors
1. A. Azmy, et al., Inorg. Chem. 2023, 62, 20142.
2. A. Azmy, et al., J. Mater. Chem. A, 2024, 12, 25730. (Inside Cover)
Metal Halide Semiconductors (MHS) feature attributes, such as the presence of large and tunable spin-orbit coupling (SOC), spin-dependent optical selection rules, and tunable Rashba/Dresselhaus (R/D) spin splitting, which render them exceptional candidates for next-generation spin-orbitronic and quantum computing devices.
Towards this end, our group focuses on the development of non-toxic, environmentally stable MHS, which are utilized as a platform for shedding light on underlying structure-property relationships in terms of R/D spin splitting for efficient spin manipulation.