Maritime oil spills and fire hazards pose significant threats to environmental safety, marine ecosystems, and critical infrastructure, demanding rapid and reliable detection strategies. In this work, we present a dual-functional smart thermochromic fiber-based self-powered detection platform designed to address these urgent safety challenges. The system integrates poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) and polydiacetylene (PDA) composite nanofibers with triboelectric nanosensor (TENS) technology, enabling real-time detection for maritime oil spill monitoring and fire safety applications. The engineered nanofibers exhibit strong oleophilicity toward hydrocarbons and hydrophobicity toward water, allowing robust discrimination between oil and seawater through distinct triboelectric voltage signatures. Temperature-dependent studies reveal systematic modulation of work function and surface potential, resulting in enhanced triboelectric output during contact electrification. These findings are further supported by density functional theory (DFT) simulations, which confirm the temperature-induced changes in work function. Moreover, the TENS demonstrates a rapid response of 630 milliseconds and sub-threshold multi-target sensing capabilities. When integrated with a wireless transmission module, it enables continuous autonomous monitoring without the need for external power sources. This makes the system particularly well suited for deployment in maritime environments and high-risk fire zones. Overall, this innovative sensing platform offers a promising approach for advanced environmental safety monitoring and has potential applications in smart cities, autonomous vehicles, and next-generation wearable safety devices, paving the way for real-time, distributed hazard detection and disaster prevention.