One key advantage of using ultrasonic fields for photocatalytic biomass conversion is their ability to regulate the concentration of dissolved oxygen in the medium. Another point to note is that when different carbon materials are used, the effectiveness of organic pollutant the decomposition in the water phase when exposed to ultrasound is enhanced. To further improve the degradation of target pollutants, sonocatalysts doped with carbon materials and integrated into carbonaceous matrices cause an increase in the production of free hydroxyl radicals in the solution. Moreover, the incorporating sonocatalysts based on carbon not only enhances free hydroxyl radical production by increasing the number of reaction nuclei, but it also facilitates the adsorption of various molecules onto the carbon surface, ready to be oxidized by newly formed free radicals. Additionally, several challenges are still facing the appropriate application of sonophotocatalysis for hydrogen production and as examples include: