The Synopsis Of M. S Research Proposal For The National Science And Technology (Nst)

Introduction

Perovskite solar cell (PSC) is the most recent invention to convert light energy into electric energy with reported efficiency up to 22. 1%. The presence of lead in the most commonly investigated perovskites material (APbX3, A= Cations, X= Anions) is considered to be a significant environmental concern because of the toxicity of lead and its associated compounds. Therefore there is a strong need to develop lead free perovskite solar cell. Current limitations impeding the commercialization of lead-based halide perovskite solar cells are (1) the toxicity, (2) bioavailability and (3) the chemical instability under ambient conditions, especially in the presence of air, humidity and light. The stability of perovskite solar cells could be improved by the exchange of the CH3NH3 cation with CH(NH2)2 and Cs ions in the triple cation approach or by the addition of Rb as A-site cation. Performance of perovskite solar cells discussed the interfacial electronic structure that means the electronic properties of interfaces between absorber (perovskite material) and hole transporting or electron transporting layer.

Different perovskite materials will be developed to reduce structural degradation, recombination and thus attain higher photocurrents and open-circuit voltages. The combination of these strategies promises to provide much more efficient and stable solar cells, paving the way for large-scale commercialization.

This research work will be devoted to a comprehensive study of the electronic structure of different perovskite materials and their interfacial interaction with adjacent ETL/HTL layer and also the stability of perovskite solar cells in different condition. Aim and objectivesWith large scale efficiency perovskite materials shows structural degradation at the interfaces between perovskite material and electron or hole transporting layer as a result PSCs exhibits structural and chemical instability at different atmospheric condition. This research work will develop different perovskite materials and study their interfacial electronic behavior to find more stable structure. Most commonly used perovskite structures are AMX3 and AMO3 (A=CH3NH3, Cs, Rb etc. ; M=Pb, Sn etc. ), here AMX3 may become organic or inorganic and AMO3 becomes organic perovskite only. Lead has been used for larger efficiency but it is also considered as a toxic element for our environment.

So, different organic-inorganic perovskite materials with or without lead were developed with high efficiency by many research groups. But for industrial outdoor application, this research project will be crucially focused on electronic behavior at the interfaces between absorber (perovskite material) and electron or hole transporting materials such as AMX3/TiO2 and AMO3/TiO2 as well as stability of perovskite solar cells. To achieve these goals we will systematically investigate different perovskite employing ab initio computer simulation methods for investigating their structural stability.

Methodology

During this research project we will perform state of the art Density Functional Theory (DFT) for calculations of the electronic structure of molecular systems. The results will provide the characterization of the electronic features of Donor-Acceptor (D-A) structures. Time FrameThe research project will consist in familiarizing with various computational techniques and performing simulation jobs, data analysis and report writing which may require around 1 year.

Socio-economic Impact

Perovskite solar cells have a large attraction to eliminate energy problem by utilize light energy from sun. Perovskite materials present important advantages, like a lower production cost and cheaper and cleaner processing techniques, which allow the production of such materials on large areas and on flexible substrates. The energy in our daily-life mostly provided by fossil fuel which is a carbon compound and has enormous amount carbon emission. Again lead free perovskite solar cells are quite safe than other perovskite solar cells which are uses lead halide perovskite material. Research will provide more efficient and stable perovskite solar cells in variable atmospheric condition. Conclusion Perovskite materials shows more efficiency than silicon based solar cells but major challenges are stability and toxicity. To convert light energy from sun to electrical energy, researcher have a great interest on lead free organic-inorganic perovskite solar cells in recent years.

In order to reduce toxicity and increase stability of PSCs, some factors should be taken under consideration such as crystal structure design, HTM layer and electrode materials preparation, thin film fabrication method, interfacial engineering, encapsulation methods, module technology and so on. Energy level alignment plays an important role in the electronic behavior of the interfaces of perovskite solar cells. Density function theory (DFT) provides well defined calculations for interfacial electronic structure and stability for perovskite material. The project will give us a solid basis to perform theoretical modeling and simulation of different perovskite material and additionally the calculations will give an important insight into the experimental results.