<p>In response to the low energy utilization efficiency of the full spectrum of solar energy and the insufficient efficiency of traditional photothermal photovoltaic conversion technology, a collaborative control method for photothermal photoelectric conversion performance based on nanofluid frequency division is proposed. This method establishes a system model and uses an improved genetic algorithm to improve the frequency division parameters of nanofluids, improving the performance of photothermal photoelectric conversion. The results show that the photothermal conversion efficiency of the proposed method reaches 75.4%, the photoelectric conversion efficiency reaches 22.6%, and the total energy efficiency of the system reaches 81.3%, which are respectively relatively improved by 7.6%, 10.2% and 8.0% when compared with the suboptimal method, proving that it can convert light energy into thermal energy and electrical energy more efficiently. The proposed method takes 1.3 seconds for calculation, which is only 62.0% of the suboptimal method, and occupies 3.2GB of memory, which is only 49.0% of the suboptimal method. This indicates that it can significantly reduce the demand for computing resources. The proposed method efficiently utilizes the full spectrum energy of solar energy through nanofluid frequency division technology, improving the efficiency of photothermal photoelectric conversion, and displaying new ideas for the development of solar energy conversion technology.</p>