First Principle Study on Lead-Free CH3NH3GeI3 and CH3NH3GeBr3 Perovskite solar cell using FHI-aims Code

Hassan Abdulsalam, Garba Babaji


An Ab-initio calculation in the framework of Density Functional Theory (DFT), as implemented in the FHI-aims package within Generalized Gradient Approximation (GGA) with the pbe parameterization was carried out in this work. Although methyl ammonium lead iodide (CH3NH3PbI3) has proven to be an effective photovoltaic material, there remains a main concern about the toxicity of lead.  An investigation into the possible replacement of CH3NH3PbI3 with CH3NH3GeI3 and CH3NH3GeBr3 as the active layer in perovskite solar cell was carried out. The electronic band structure, band gap energy and dielectric constants were calculated for CH3NH3GeI3 and CH3NH3GeBr3. The effect of temperature on linear thermal expansion coefficient and temperature dependence of lattice constant were studied in the temperature range of 273 to 318 K. Band gap shift due to lattice expansion was also studied. The dielectric constants of these materials were also determined. The energy band gap calculated for CH3NH3GeI3 and CH3NH3GeBr3 at their respective equilibrium lattice constant are 1.606 and 1.925eV respectively. A numerical simulation with some of these materials as the active layer in a perovskite solar cell was performed using General-purpose Photovoltaic Device Model (GPVDM) and the conversion efficiency of the resulting solar cell was obtained. Conversion efficiency of 10% and 8.4% were obtained for CH3NH3GeI3 and CH3NH3GeBr3 respectively.


CH3NH3GeI3, CH3NH3GeBr3, DFT, FHI-aims, Energy-bandgap, lattice constant, total energy, dielectric constants, linear-thermal-expansion-coefficient and Conversion Efficiency

Full Text:



Sarkar S. K., Hodes G., Kronik L. and Cohen H., Defect-dominated charge transport in Si-supported CdSe nanoparticle films. The Journal of Physical Chemistry C, 2008. 112(16): p. 6564-6570.

Yuan. S, Tang Q., Hu B., Ma C., Duan J and He B. Efficient quasi-solid-state dye-sensitized solar cells from graphene incorporated conducting gel electrolytes. Journal of Materials Chemistry A, 2014. 2(8): p. 2814-2821.

Völker, S.F., S. Collavini, and J.L. Delgado, Organic charge carriers for perovskite solar cells. Chem Sus Chem, 2015. 8(18): p. 3012-3028.

Kojima, A., Teshima, K., Shirai, Y and Miyasaka, T., Organometal halide perovskites as visible-light sensitizers for photovoltaic cells. Journal of the American Chemical Society, 2009. 131(17): p. 6050-6051.

Sha Wei EI, Ren, Xingang, Chen Luzhou and Choy Wallace CH,

The efficiency limit of CH3NH3PbI3 perovskite solar cells. Applied

Physics Letters, 2015. 106(22): p. 221104.

Abate, A., Perovskite Solar Cells Go Lead Free. Joule, 2017.

Arbuznikov, A., Hybrid exchange correlation functionals and potentials: Concept elaboration. Journal of Structural Chemistry, 2007. 48: p. S1-S31.

Blum, V., Gehrke, R., Hanke, F., Havu, P., Havu, V., Ren, X., Reuter,K. and Scheffler, M., Ab initio molecular simulations with numeric atom-centered orbitals. Computer Physics Communications, 2009. 180(11): p. 2175-2196.

Oku, T., Crystal structures of CH3NH3PbI3 and related perovskite compounds used for solar cells, Solar Cells-New Approaches and Reviews. 2015, InTech.

Momma, K. and F. Izumi, VESTA: a three-dimensional visualization system for electronic and structural analysis. Journal of Applied Crystallography, 2008. 41(3): p. 653-658.

Hanwell, M. D., Curtis, D. E., Lonie, D. C., Vandermeersch, T., Zurek E. and Hutchison, G. R.,Avogadro: an advanced semantic chemical editor, visualization, and analysis platform. Journal of cheminformatics, 2012. 4(1): p. 17.

Setyawan, W. and S. Curtarolo, High-throughput electronic band structure calculations: Challenges and tools. Computational Materials Science, 2010. 49(2): p. 299-312.

Franz, K. and L. Sergey, Tutorial II: Periodic Systems Manuscript for Exercise Problems: Presented at the Hands-on Tutorial Workshop on ab Initio Molecular Simulations at Fritz-Haber-Institut der Max-Planck-Gesellschaft Berlin. 2013, August.

Christian, C., Tutorial IV: Phonons, Lattice Expansion, and Band-gap Renormalization Manuscript for Exercise Problems: Presented at the Hands-on Tutorial Workshop on ab Initio Molecular Simulations at Fritz-Haber-Institut der Max-Planck-Gesellschaft Berlin. 2015, July.

MacKenzie, R. C., Kirchartz, T., Dibb, G. F. A and Nelson, J.., Modeling nongeminate recombination in P3HT: PCBM solar cells. The Journal of Physical Chemistry C, 2011. 115(19): p. 9806-9813.

Yuan, Ye Xu, Run, Xu, Hai-Tao Hong, Feng Xu, Fei and Wang, Lin-JunNature of the band gap of halide perovskites ABX3(A= CH3NH3, Cs; B = Sn, Pb; X= Cl, Br, I): First-principles calculations. Chin. Phys. B 2015. 24(11): p. 5.

Heyd, J., G.E. Scuseria, and M. Ernzerhof, Hybrid functionals based on a screened Coulomb potential. The Journal of Chemical Physics, 2006. 118(18): p. 8207-8215.

Yuqiu, J., Yuanyuan, L. J., Li Mang, N. and Zhenqing, Y.,Exploring electronic and optical properties of CH3NH3GeI3 perovskite: Insights from the first principles. Computational and Theoretical Chemistry, 2017. 1114: p. 20-24.

Hoefler, S.F., G. Trimmel, and T. Rath, Progress on lead-free metal halide perovskites for photovoltaic applications: a review. Monatsh Chem, 2017. 148(5): p. 795-826.

Dolling, G. and R. Cowley, The thermodynamic and optical properties of germanium, silicon, diamond and gallium arsenide. Proceedings of the Physical Society, 1966. 88(2): p. 463.

Park, N.-G., Methodologies for high efficiency perovskite solar cells. Nano convergence, 2016. 3(1): p. 1-13.

Abdulsalam, H., G. Babaji, and H.T. Abba, The Effect of Temperature and Active layer thickness on the Performance of CH3NH3PbI3 Perovskite Solar Cell: A Numerical Simulation Approach. Journal for Foundations and Applications of Physics, 2018. 5(2): p. 141-151.


  • There are currently no refbacks.

Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

ISSN: 2394-3688

© Science Front Publishers