**7. Neoteric challenges in development of 2d photovoltaic cells**

It is crucial that the entire energy of any absorbed photon is harvested for next-generation photovoltaics. The unique features of 2d layered materials such as high crystalline quality, transparency, atomic thickness, make them special to use in photovoltaic solar cells. Thus, it is important to synthesized and demonstrate 2d flexible photovoltaic devices on industrial scale. While some different issues and problems will be faced by the experimentalist regarding an efficiency performance. The specific requirements in the fabrication of photovoltaic devices are the large-area synthesis, highly controllable, low cost, atomically thin, and recyclable fabrication of materials and their devices. The above features are specified not only for all potential electronic devices but also for optoelectronic devices. Increased number of layers of 2d materials, the conductivity of the material improves at the cost of reduced transparency. The application of 2dmaterials like TMDs and perovskites in photovoltaic devices has also been investigated over the last few years. The advantages of using such materials for solar cells have been explored based on the high absorption coefficient of these materials in the visible to the near-infrared part of the solar spectrum. So there is a need for more investigation of the heterostructure based on these materials, which can synergize the performance of the

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**Author details**

**8. Conclusion**

Manoj Kumar Singh1

\*, Pratik V. Shinde2

\*Address all correspondence to: manojksingh@cuh.ac.in

provided the original work is properly cited.

, Pratap Singh1

In this chapter, we have enlightened specific properties and synthesis techniques of graphene, TMDs, and perovskite. We have described recent progress made with graphene, graphene-based 2D materials for solar photovoltaics. In addition, 2d Schottky junction, homojunction, and heterojunction are explained briefly. The unique account of the charge carrier transport layer as ETL and HTL has been done fairly. Moreover, regular n-i-p and inverted p-i-n structure are the key features. Furthermore, 2DRP perovskite, upconversion/downconversion of perovskite cells are also discussed briefly. In the last of the section very recent developments on 2d perovskite photovoltaic cells have been critically explained with the facts. Various challenges in the fabrication and development of today's devices are pointed out. Therefore, the outlook towards 2d materials should be optimistic and needs more attention in the near future.

1 Department of Physics under School of Engineering and Technology (SOET),

Central University of Haryana (CUH), Mahendergarh, Haryana, India

2 Centre for Nano and Material Sciences, Jain University, Bangalore, India

3 Department of Applied Physics, Delhi Technological University, Delhi, India

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

and Pawan Kumar Tyagi3

*Two-Dimensional Materials for Advanced Solar Cells DOI: http://dx.doi.org/10.5772/intechopen.94114*

device. Although the efficiency of perovskite solar cells has been boosted to over 25%, further improving the efficiency towards their theoretical Shockley–Queisser efficiency limit of more than 30% and improving the stability towards commercial application deserve more intensive research. The micromechanical cleavage method provides us structural study and device performance but this cannot be used as industry level as low production rate and low yield. This lack noted by the scientific community and remarkable advancement has been achieved by fabricating 2d materials at the industry level within the past few years. Moreover, TMDs, hBN, graphene, and perovskite are critically fabricated with different methods like physical vapor transport, CVD, layer by layer conversion; etc. The samples obtained in this way have properties like controllable thickness, electronic properties scalable sizes, and high crystal quality. Also, a liquid-based wet chemical method provides two unique requirements high control power and low-cost manufacturing of atomically thin 2D nanomaterials. Moreover, it is necessary to achieve excellent crystal quality and film uniformity before using the LBWC technique in large scale manufacturing.

*Two-Dimensional Materials for Advanced Solar Cells DOI: http://dx.doi.org/10.5772/intechopen.94114*

device. Although the efficiency of perovskite solar cells has been boosted to over 25%, further improving the efficiency towards their theoretical Shockley–Queisser efficiency limit of more than 30% and improving the stability towards commercial application deserve more intensive research. The micromechanical cleavage method provides us structural study and device performance but this cannot be used as industry level as low production rate and low yield. This lack noted by the scientific community and remarkable advancement has been achieved by fabricating 2d materials at the industry level within the past few years. Moreover, TMDs, hBN, graphene, and perovskite are critically fabricated with different methods like physical vapor transport, CVD, layer by layer conversion; etc. The samples obtained in this way have properties like controllable thickness, electronic properties scalable sizes, and high crystal quality. Also, a liquid-based wet chemical method provides two unique requirements high control power and low-cost manufacturing of atomically thin 2D nanomaterials. Moreover, it is necessary to achieve excellent crystal quality and film uniformity before using the LBWC technique in large scale manufacturing.
