Dr Ibrahim Dar

Biography

Ibrahim Dar is a Royal Society University Research Fellow in the Cavendish Laboratory at the University of Cambridge. From 2018 to 2020, he was an Advanced Swiss National Science Foundation Post-Doctoral Fellow in the group of Professor Sir Richard Friend, University of Cambridge. Prior to this, he worked as a Post-Doctoral Scientist with Professor Michael Graetzel at Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland (2014-2018).

For his postdoctoral research at EPFL, he was awarded the prestigious Zeno Karl Schindler-EPFL Prize for particular excellence in the field of sustainability and was twice awarded a special prize by the School of Basic Sciences, EPFL, Switzerland.

During his PhD, he was awarded the Swiss Government Excellence Research Scholarships for two consecutive years (2012-2014), which allowed him to work in Professor Graetzel’s group as a guest PhD student. Ibrahim’s group conducts interdisciplinary research that combines solid-state chemistry, photophysics, and nanoscience to design and understand new functional materials with desired structural and optoelectronic properties for energy-oriented applications.

Research

Emerging Semiconductors for Energy Applications

Our interdisciplinary research in solid-state chemistry, physics, and nanoscience encompasses designing and understanding active materials (light absorbers/emitters) and charge conductors for their applications in emerging device systems.

The main research activities span:

• Developing Perovskite Devices
• Probing Interfacial Processes in Optoelectronic Devices
• Tailoring of Mixed Conduction in Perovskite Semiconductors
• Nucleation and Crystallisation of Semiconductors at the Nano-regime

Selected Publications:

1. Arora, A. Greco, S Meloni, A Hinderhofer, A Mattoni, U Rothlisberger, J Hagenlocher, C Caddeo, S M. Zakeeruddin, F Schreiber, M. Graetzel, R H. Friend, and M. IBRAHIM. DAR*. Kinetics of Metal Halide Perovskite Conversion Reactions at the Nanoscale. Communication Materials, 2022, 3, 22. DOI: s43246-022-00239-1
2. Ahlawat, C. Clementi, F. Musil, M.-A. Filip, M. IBRAHIM DAR Lattice-Matched Heterogeneous Nucleation Eliminates Defective Buried Interfaces in Halide Perovskites Chemistry of Materials 2025, 37, 6, 2177–2191 DOI: 10.1021/acs.chemmater.4c03034
3. N. Arora,† M. IBRAHIM DAR,†* A. Hinderhofer, N. Pellet, F. Schreiber, S. M. Zakeeruddin, M.  Grätzel* Perovskite solar cells with CuSCN hole extraction layers yield stabilized efficiencies greater than 20%. Science 2017, 358, 768-771. DOI: 10.1126/science.aam5655 (†= authors contributed equally)
4. Y. Wang, M. IBRAHIM. DAR,* L.K. Ono, T. Zhang, M. Kan, Y. Li, L. Zhang, X. Wang, Y. Yang, X. Gao, Y. Qi,* M. Grätzel,* Y. Zhao* Thermodynamically stabilized β-CsPbI₃ based perovskite solar cells with efficiencies >18%, Science, 2019,  365, 591-595. DOI: 10.1126/science.aav8680  
5. Baumeler, N. Arora, A. Hinderhofer, S. Akin, A. Greco, M. Abdi-Jalebi, R. Shivanna, R. Uchida, Y. Liu, F. Schreiber, S. M. Zakeeruddin, R. H. Friend, M. Graetzel and M. IBRAHIM. DAR*. Minimizing the Trade-Off between Photocurrent and Photovoltage in Triple-Cation Mixed-Halide Perovskite Solar Cells. The Journal of Physical Chemistry Letters, 2020, 11, 10188-10195. DOI: 10.1021/acs.jpclett.0c02791
6. Y. Liu, S.Akin, L. Pan, R. Uchida, N. Arora, J. V.  Milic, A. Hinderhofer, F. Schreiber, A. R. Uhl, S. M. Zakeeruddin, A. Hagfeldt, M. IBRAHIM DAR,* M. Grätzel* Ultra-Hydrophobic 3D/2D Fluoroarene Bilayer-Based Water-Resistant Perovskite Solar Cells with Efficiencies Exceeding 22%. Science Advances, 2019, 5, eaaw2543 DOI: 10.1126/sciadv.aaw2543
7. Liu, S. Akin, A. Hinderhofer, F. T. Eickemeyer, H. Zhu, J.-Y. Seo, J. Zhang, F. Schreiber, H. Zhang, S. M. Zakeeruddin, A. Hagfeldt, M. IBRAHIM. DAR* and M. Grätzel. Stabilization of Highly Efficient and Stable Phase-Pure FAPbI₃ Perovskite Solar Cells by Molecularly Tailored 2D-Overlayers. Angew. Chem. Int. Ed.,2020, 59, 15688. DOI: 10.1002/anie.202005211
8. M. IBRAHIM DAR,* G. Jacopin, S. Meloni, A. Mattoni, N. Arora, A. Boziki, S. M. Zakeeruddin, U. Rothlisberger, M. Graetzel. Origin of unusual bandgap shift and dual emission in organic-inorganic lead halide perovskites. Science Advances 2016, 2, e1601156. DOI: 10.1126/sciadv.1601156
9. N. Arora,† M. IBRAHIM DAR,†* M. Abdi-Jalebi, F. Giordano, N. Pellet, G. Jacopin, R. H. Friend, S. M. Zakeeruddin, M. Grätzel. Intrinsic and Extrinsic Stability of Formamidinium Lead Bromide Perovskite Solar Cells Yielding High Photovoltage. Nano Letters 2016, 16, 7155–7162. DOI: 10.1021/acs.nanolett.6b03455  (†= authors contributed equally)
10. X. Li, M. IBRAHIM DAR, C. Yi, J. Luo, M. Tschumi, S. M. Zakeeruddin, M. K. Nazeeruddin, H. Han, M. Grätzel* Improved performance and stability of perovskite solar cells by crystal crosslinking with alkylphosphonic acid ω-ammonium chlorides. Nature Chemistry 2015, 7, 703-711. DOI: 10.1038/nchem.2324