The groups’ focus is the Molecular Engineering of Functional Materials for Photovoltaic and Light-emitting applications. In the field of molecular-based photovoltaic devices, dye-sensitized solar cells (DSCs) have reached an efficiency of over 13%. This efficiency level, coupled with the use of inexpensive materials and processing, has stimulated momentum to industrialize this technology. In these cells, the sensitizer, located at the junction between electron and hole transporting phases, absorbs sunlight and injects an electron and a hole into the n- and p-type materials, respectively. The former is an inorganic n-type wide bandgap oxide semiconductor (typically TiO2 anatase), and the latter is a liquid electrolyte or p-type hole transporter. The generated free charge carriers, travel through the nanostructured oxide to be collected as current at the external contacts. The significant advantage of DSCs is that they achieve the separation of light harvesting, and charge carrier transport, thus the maximum power point is virtually independent of light level therefore useful in all climate conditions. The general losses in dye-sensitized solar cells are due to the lack of sensitizer absorption in the near IR region, and the loss-in-potential from the optical band gap to the open-circuit voltage. The goal of the group is to engineer at molecular level novel panchromatic sensitizers and functionalized hole-transporting materials to achieve power conversion efficiency over 18%.
Recently organohalide lead perovskites have revolutionized the scenario of emerging photovoltaic (PV) technologies, with certified efficiency of 22.5% based on a perovskite solar cell. The group is aiming to enhance power conversion efficiency of perovskite solar cells beyond 25%, and stability using functionalized electron and hole transporting materials. Our group has pioneered a new concept of using 2D/3D interface to enhance stability under light soaking and heat for more than 12,000 h. Our results demonstrated an impressive improvement in device stability due to the favorable self-organization and interface energetics of the 2D/3D interface. This novel strategy opens a new field of possibilities, moving from uniform to gradually organized 3D/2D PSCs. The highest efficiency using 3Dimensional/2Dimentional perovskite layers in our laboratory is over 23.13%, and a mini-module 15 cm2 efficiency is 17.3%. These results emanate from the compositional engineering of the cations (A) and anions (X), using a nonstoichiometric lead iodide precursor and a solvent-engineering method to grow the over layer of perovskite on the mesoporous layer.
Comparison of the AX3 stacking sequence (between three different hexagonal lead halide perovskite polytypes i.e. 2H (‘delta phase’), 4H, 6H and the rhombohedral perovskite phases 3C, 3R.
Retarding thermal degradation in hybrid perovskites by ionic liquid 1-(4-ethenylbenzyl)-3-(tridecafluorooctyl)-imidazolium iodide (ETI).
Photographs showing the pure MAPbI3 (left) and mixed 1% ETI (right) films aged over 2 months in ambient air, 50 ± 5% humidity at room temperature.
Using solar cells to generate hydrogen, and reduction of CO2 to fuels is ultimately an environmentally friendly process that reduces greenhouse gases. Therefore, the group will explore H2 generation via water splitting using sunlight, and CO2 reduction to liquid fuels using molecularly engineered transition metal complexes. These tailored metal complexes can act as inner sphere electron transfer agent to activate CO2.
The inverse process of solar cell is producing light from electricity in organic light emitting diodes (OLEDS), which is also one of the main focuses of the group. Here the goal is to engineer highly phosphorescent emitters with blue, green and red colors for display and lighting applications.
- According to the Web of Science, Nazeeruddin is the highly cited researcher, 2014, 2015, 2016, 2017 and 2018.
- Nazeeruddin is the World’s Most Influential Scientific Minds in 2015 (one of the 19 scientists identified by Thomson Reuters as the World’s Most Influential Scientific Minds (from all scientific domains). https://ece.nl/wp-content/uploads/Thomson-Reuters-2015.pdf.
- According to the Web of Science, Nazeeruddin is the 5thmost cited chemist in the world, and one of the World’s Most Influential Scientific Minds. https://clarivate.com/hcr/wp-content/uploads/2017/11/2017-Highly-Cited-Researchers-Report-1.pdf.
- One of the 24 Highly Cited Researchers named in three ESI fieldsHighly 2018https://hcr.clarivate.com/
- Nazeeruddin, has been listed among the Top 10 researchers in perovskite solar cell research field by the Times Higher Education (THE) https://www.timeshighereducation.com/data-bites/top-universities-and-researchers-perovskite-solar-cell-research#survey-answer.