Quantum dot as light harvester nanocrystals for solar cell applications

Quantum dot as light harvester nanocrystals for solar cell applications

M. Patel, S. Sahu, A. K. Verma, P. Agnihotri, Surya Prakash Singh, Ramanuj Narayan, Sanjay Tiwari

In this article we are reviewing the application of quantum dot nanocrystals as light harvesters for solar cell applications. Three foremost ways to make use of semiconductor quantum dots in solar cells are metal-semiconductor photovoltaic cell, polymer-semiconductor solar cell and quantum dot sensitized solar cell. Band energies can be controlled by size change in quantum dots which gives new ways to control the response and efficiency of the solar cell. Quantum dot solar cell reduces heat waste by multiple electron generation (MEG) and converts up to three electrons per photon. Therefore, more than 100% quantum efficiency is possible for quantum dot solar cells. Furthermore Quantum dot forms one or more intermediate bands (IBs) in the host semiconductor bandgap, enabling two-step absorption of sub-band gap photons. Since the IBs are electrically isolated from Valance Band and Conduction Band, their introduction increases short circuit current (Isc) and keeps open circuit voltage (Voc) unreduced.

Keywords
Nanocrystals, Solar Cell, Quantum Dot, Multiple Electron Generation, Intermediate Bands

Published online 8/2/2017, 17 pages

DOI: https://dx.doi.org/10.21741/9781945291371-4

Part of Recent Advances in Photovoltaics

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