Tang, Z. 2025. Research on a Review of Derivative Methods of Classical Hydrothermal/Solvothermal Synthesis Methods, Taking SnO₂/r-GO Gas-sensitive Composite Materials as Examples. International Journal of Electric Power and Energy Studies. 4, 2 (Sep. 2025), 44–55. DOI:https://doi.org/10.62051/ijepes.v4n2.06.