Control over Power Conversion Efficiency of BHJ Solar Cells: Learn more from Less, with Artificial Intelligence

Document Type : Original Article


1 Department of Organic Colorants, Institute for Color Science and Technology, P.O. Box 16765-654, Tehran, Iran

2 Center of Excellence for Color Science and Technology, Institute for Color Science and Technology, P.O. Box 16765-654, Tehran, Iran

3 Petrochemical Research and Technology Company (NPC-rt), National Petrochemical Company (NPC), Tehran, Iran

4 Department of Resin and Additives, Institute for Color Science and Technology, P.O. Box: 16765-654, Tehran, Iran


Harvesting the energy from the sun through the bulk heterojunction (BHJ) solar cells need materials with specific electronic characteristics. However, any promising material if cast improperly in cells will end into low or even null power conversion efficiency (PCE). Cell casting optimization is a time/material consumable step in any photovoltaic manufacturing practice. In this study, we showed that how the artificial intelligence (AI) could help to find optimum values of device preparation variables. For this purpose, an in-house code will catch the input variables (donor: acceptor ratio, spin casting rate, annealing temperature); learn the trends by the hybrid artificial neural network (ANN), genetic algorithm (GA) and optimize the output results simultaneously. The results showed that ANN/GA is capable to learn the trends of relatively small size dataset without over-fitting. This study highlights that how implementing the suggested AI model can help to learn more information and find the optimum recipe from less number of experiments with the highest precision.


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