This question has been answered in reference books covering the solar cells materials and structures.
The best material which can absorb the greatest portion of the incident solar cell
and produces free electrons and holes.
That has the highest built in voltage for their junctions ans so the highest open circuit voltage
That its junctions has the most square shape of the I-V curve.
The smallest possible Rs.
The two last factors lead to high fill factor.
A single junction and a single material can not satisfy these requirements simultaneously. In case of a single junction one has to compromise the first two factors.
So, the best solar cells is a multijunction multi material solar cells.
I would like that you see the reference:
Chapter Solar Cells and Arrays
Best wishes
Dear Deepak
The main goal of a design for a solar cell is to obtain the highest possible power conversion efficiency. However, a long time ago the maximum theoretical efficiency that could be reached by a single junction solar cell was reported by William Shockley and Hans J. Queisser,
Article Detailed Balance Limit of Efficiency of P-N Junction Solar Cells
In this article, a simplified model was used to find out the limits and the maximum efficiency of single-junction solar cells. The maximum efficiency is found to be 30% for an energy gap of 1.1. Shockley and Queisser used in their model the black body spectrum as an approximation to the solar spectrum. Later on, another study used the measured global solar spectra (AM1.5G) for the solar spectrum, and get an efficiency limit of 33.7% for a solar cell with a bandgap of 1.34 eV.
Article Tabulated values of the Shockley–Queisser limit for single j...
So, whatever the material selection, the maximum efficiency of a single junction solar cell can not exceed this limit. Anyway, your choice needs to be based on the criteria discussed in these articles. Moreover, the design is very important also to improve the efficiency of a solar cell.
Some of the factors that have to be taken into account for material to obtain high performance of solar cells are: Long electron-hole diffusion length; High and balanced carrier mobility; low nonradiative Auger recombination; and high internal quantum efficiency; etc.
greetings
M.Elshorbagy
The materials choosed for the photovoltaic applications must be have a bang gap adapted at the solar radiation ,so it must have a band gap between 1.1-1.8eV and good absorption coefficient >10 5.
According to Shockley and Queisser, the maximum theoretical solar conversion efficiency for a single p-n junction photovoltaic cell is achieved at a band gap of 1.34eV, silicon with a band gap of 1.1eV is used in approximately 90% of solar cell semiconductors sold today. Silicon PV comes in a number of different forms like crystalline, amorphous silicon
To make a good solar cell, have a good vision and will. rest will come automatically with time.
Dear Deepak,
You can fabricate good solar cells structure by using Kesterite Cu2ZnSnS4 (CZTS) absorber. This material has drawn recently a lot of attention due to the utility of low cost, earth abundant Zn and Sn elements to replace In and Ga in Cu(In,Ga)Se2 (CIGS) absorber layers. The used materials such as In, Ga, Se, Cd and Te are still rare and expensive. CZTS has a direct band gap located in the same range as CIGS (1.4–1.5 eV) which is considered ideal for efficient solar absorption and it possesses high absorption coefficient of 104–105 cm−1.
good luck.
Important goal of solar cell design to obtain the maximum conversion efficiency, better to use nano particles cells to achieve the maximum efficiency
Dear Deepak,
Several factors affect a cell's conversion efficiency value, including its reflectance, thermodynamic efficiency, charge carrier separation efficiency, charge carrier collection efficiency and conduction efficiency values. Because these parameters can be difficult to measure directly, other parameters are measured instead, including quantum efficiency, open-circuit voltage (VOC), short circuit current and Fill factor. Reflectance losses are accounted for by the quantum efficiency value, as they affect "external quantum efficiency." Recombination losses are accounted for by the quantum efficiency, VOC ratio, and fill factor values. Resistive losses are predominantly accounted for by the fill factor value, but also contribute to the quantum efficiency and VOC ratio values.
The world record for solar cell efficiency at 47.1% was achieved by using multi-junction concentrator solar cells, developed at National Renewable Energy Laboratory, Golden, Colorado, USA In 2019.
This is above the standard rating of 37.0% for polycrystalline photovoltaic or thin-film solar cells. I give you the best substrate CIGS soalr structure : ZnO:Al/CdS/CIGS(co-evaporation)/Mo/SLG (22.9% in 2019) .
In attached you will find our last article about CIGS fabrication by rf-Sputtering:
- https://www.sciencedirect.com/science/article/abs/pii/S0022286020307821
Good luck.
This question has been answered in reference books covering the solar cells materials and structures.
The best material which can absorb the greatest portion of the incident solar cell
and produces free electrons and holes.
That has the highest built in voltage for their junctions ans so the highest open circuit voltage
That its junctions has the most square shape of the I-V curve.
The smallest possible Rs.
The two last factors lead to high fill factor.
A single junction and a single material can not satisfy these requirements simultaneously. In case of a single junction one has to compromise the first two factors.
So, the best solar cells is a multijunction multi material solar cells.
I would like that you see the reference:
Chapter Solar Cells and Arrays
Best wishes
Another important issue is the material stability and reliability in addition to the availability. Up till now silicon and other metallic semiconductors stand in the front. In spite of the lower cost and higher conversion efficiency of the halide perovskite it is unstable in addition to the inclusion of Pb which is toxic.
So, the material be also untoxic and environment friendly.
Easy processing is also a requirement for good solar cell materials.
Best wishes
Hello Deepak,
A good solar cell, in order to flourish in current pv market must not only give satisfactory performance but other factors like easy processing condition, low cost, good device lifetime, non-toxicity etc are equivalently important.
A good solar cell must generate maximum number of electron hole pair upon the action of incident photons.
For a material to be used in PV application must posses the properties:
1- the ideal bandgap of the material to be used must lie between 1.0-1.7eV. As in this range electrons can be easily be free without generation of much heat
- must have high abs coefficient nearly over 10^5/cm
- generated exciton pairs can be easily disassociate
- the generated charge carrier must have higher carrier lifetime. Like in case of Perovskite solar cells it's about 1usec. High lifetime is preferable because it enables higher rate of charge collaboration by the charge collecting contacts thereby avoiding recombination
- the constituent layers n interfaces must be uniform n defect free so that easy charge pair generation n collection occurs.
Best wishes
For a good solar cell we need to design it in a way that the recombination decreases at the interfaces since the bulk recombination has already been reduced by improvements in the materials. So the interface materials are of importance.
Also increasing generation in the cell by reduction of reflection using texturing schemes and ARC can also improve the generation rate and thus the solar cell performance.
Further the cost to benefit ratio needs to be taken into consideration. We cannot call a solar cell with good efficiency and very high cost as a good solar cell.
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