Due to the difficulty of absorbing viscous crude oil, there is an urgent need for carbon sponges with excellent photothermal properties and oil-water separation capabilities to reduce viscosity and facilitate oil absorption. However, the preparation of high-temperature carbonization leads to poor mechanical properties, low absorption capacity, and stringent preparation conditions. To solve these challenges, a highly hydrophobic flame-retardant melamine sponge (CPBA@CMS) is designed by assembling sponge at the interface of cobalt–iron Prussian blue (CoFe-PBA) derived from metal–organic frameworks (MOFs) and conducting low-temperature catalytic carbonization under nitrogen. The results demonstrate that CPBA@CMS exhibits excellent superhydrophobic properties (water contact angle = 169.7°) and oil absorption capacity (80.7–219.5 g g−1). Furthermore, CPBA@CMS displays remarkable photothermal effects and thermal conductivity, making it adaptable to various environmental conditions. It can rapidly rise to 141 °C under 1 kW m−2 solar irradiation, with the maximum oil absorption rate reaching 98% and the highest oil absorption capacity at 105.5 g g−1. Additionally, CPBA@CMS shows significant fire safety performance, reducing heat release rate by 84.2%, smoke factor by 97.5%, and CO release rate by 81.4%, respectively. It provides an efficient, safe, and sustainable practical solution for effectively addressing spills of crude oil.