<p>Titanium dioxide (TiO₂) is widely regarded as one of the most promising semiconductor materials for photocatalysis. In this study, through defect engineering, the strong interaction between F⁻ ions and surface Ti⁴⁺ is utilized to induce the generation of oxygen defects, thereby achieving selective etching and exposure of the high-energy {101} crystal plane. At the same time, the coordination effect of Ni on the surface metal active site not only promotes the transition of the forbidden band energy level, but also effectively narrows the band gap of TiO₂. Through systematic characterization, the successful coordination of Ni and the enhancement of the high-energy state crystal plane stability were confirmed. BET specific surface area test shows that the large specific surface area of Ni-TiO₂ samples provides more surface active sites for photocatalytic reactions. Photoelectric performance tests further show that the introduction of double defect engineering significantly improves the separation and migration efficiency of TiO₂ photogenerated carriers. Degradation experiments showed that Ni-coordinated TiO₂ could efficiently degrade phenol pollutants within 60&#xa0;min, exhibiting excellent photocatalytic activity. Capture experiments further confirmed that the coupling between non-radical ¹O₂ and free radical •OH is the main active species in photocatalytic degradation. The synergistic effect of the generation of high-energy state facets and Ni coordination significantly improves the separation and migration of photogenerated carriers, thereby enhancing the photocatalytic performance. This work provides a reliable defect engineering strategy for improving the photocatalytic performance of TiO₂.</p> Graphical Abstract <p></p> <p>In this study, through defect engineering, the strong interaction between F⁻ ions and surface Ti⁴⁺ is used to induce the generation of oxygen defects, thereby achieving selective etching and exposure of high-energy {101} crystal planes. At the same time, the coordination effect of Ni on the surface metal active sites not only promotes the transition of the forbidden band energy level, but also effectively narrows the band gap of TiO₂. By carefully designing the photocatalytic process, direct degradation of phenol was achieved under the coupling of non-radicals and free radicals. The improvement in photocatalytic activity is due to the increase in specific surface area, which not only broadens the light absorption capacity but also significantly improves the separation and migration of photogenerated carriers. The capture experiment further verified the efficient catalytic mechanism of the Ni-TiO₂/phenol system, demonstrating that the synergistic effect of the high-energy {101} crystal plane and the highly active Ni coordination was fully utilized to promote the generation of •OH radicals during the reaction and effectively drive the conversion of oxygen molecules into ¹O₂ through vacancy oxidation. This study not only provides a useful reference for the design of high-efficiency and low-energy photocatalysis, but also provides a new solution for the removal of phenol pollution in coal chemical wastewater.</p>