This project studies a stereochemical and thermodynamic analysis of nanoparticles used in the photoactive layer of solar cells through molecular modeling. The primary objective is to determine the thermodynamic energy of nano-scaled compounds. This is to evaluate their suitability to improve the physicochemical properties of the materials used in the photoactive layer of the solar cells. There are a few considered such as: thermodynamic stability (optimized energy), reactivity (dipole moment), and electrostatic potential distribution. Using a Universal Force Field equipped in the computational program, several nano-scaled materials were modeled, geometries were optimized, and then the major factors were compared. Among the eval uated D style compounds, Benzothiadiazole (D2/BTD) exhibited the lowest optimized energy. This indicates superior thermodynamic stability and making it a promising candidate for potential photoactive layers. Quinoxaline (D4/QX) showed a moderate optimized energy but demonstrated the highest dipole moment. This suggests excellent reactivity and charge-transfer capability. This is critical for efficient solar cells and DSSCs performance. Benzotriazole (D5/BTA) displayed intermediate performances in both parameters. This indicates a balanced trade-off between stability and conductivity. Additionally, metallophthalocyanines(MPc) were assessed for their stereochemical properties. These macrocyclic compounds exhibited unique electrostatic potential maps with pronounced color variation, indicating highly delocalized electron clouds and strong intramolecular charge transfer. Except for AlPc and MgPc, other molecules showed a similar distribution of electrons in the electrostatic potential map with the positive regions in the center. Considering the optimized energy and the ability to generate singlet oxygens, MgPc seemed to be the most suitable to be used for a photosensitizer. The results indicate that balancing low optimized energy, high dipole moment, and favorable electrostatic potential is importanl for designing efficient DSSC photoactive layers.

References

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