Tannic Acid Intercalated Tb Doped Graphene Oxide Layer: A Multifunctional Hybrid Photothermal Structure for Solar Energy Driven Water Purification, Power Generation, and Disinfection

The development of solar energy‐driven multifunctional photothermal materials represents a key step toward bridging energy harvesting with environmental sustainability initiatives. Herein, a tactically designed tannic acid intercalated, terbium‐doped graphene oxide (TA–Tb 3+ –GO) framework is presented. This framework demonstrates synergistic photothermal conversion and a permeable structure that facilitates proficient capillary action, permitting rapid water transmission and steam discharge. Surface temperature of the optimized TA–Tb 3+ –GO framework reaches over 60 °C within 5 min of exposure to 1 Sun, highlighting its potential as an effective a solar water purifier. It achieves an interfacial water evaporation rate of 1.4 kg m −2 h −1 under 1 Sun illumination, with of 98% conversion efficiency. Its cell viability tests reveal potential antimicrobial efficacy, successfully killing both Gram‐positive and Gram‐negative bacteria, suggesting its prospective for photothermal therapy. Moreover, when integrated with a commercial thermoelectric unit, the TA–Tb 3+ –GO framework exhibits exceptional photothermoelectric generation efficiency with an achieved power density of 5.8 Wm −2 , demonstrating its potential for electrical power generation. In summary, the framework's tremendous stability, lack of photoinduced leaching, ability to yield clean water out of seawater, antimicrobial features, and reutilization make TA–Tb 3+ –GO an archetype for sustainable freshwater and power production applications.