• Carbon materials enhance photocatalytic efficiency in Z-scheme and S-scheme heterojunctions by promoting charge separation and reducing recombination losses.
• Integration of carbon materials extends the spectral response range, enabling better utilization of solar energy for H2 generation and CO2 reduction.
• Recent advances demonstrate significant progress in carbon-based heterojunctions for clean energy production, with potential for scalable applications.
• Challenges remain in optimizing synthesis and stability of carbon-based photocatalysts, guiding future research directions.