Despite metal oxides offer excellent characteristics in the field of photocatalysis, they often suffer from charge carrier recombination as well as limited visible response, which indeed reduce the charge kinetics process and ultimately reduce the photocatalytic output. Defect engineering is a sophisticated technique to manufacture defects and alter the geometric structure and chemical environment of the host. The present study provides an all-inclusive outline of recent developments on the classification of metal oxide defects based on the dimensions of a host crystal lattice. Precisely, surface modification of metal oxides through 0D (point), 1D (line), 2D (planar), and 3D (volume) defects with their subsequent mechanism and impact on photocatalytic performance are presented. By wisely amending the morphology (cores along with the shells) and electronic structure of metal oxide photocatalysts (TiO₂, ZnO, Bi₂O₃, Fe₂O₄ etc.) through different attuned and veritable approaches, their photocatalytic activity can be substantially improved. Optimal studies on defect engineering not only expose the altered physicochemical features but also modulate the electron-hole pair dynamics, stability, and active radical production for various photoredox reactions. Altered atomic, as well as electronic configuration, facilitated a photocatalyst material to have different optical features, adsorption properties along with improved carrier transfer as well as isolation rate. Thus, the systematic exploration of photocatalytic rudiments of defect rich metal oxide for various applications such as H₂ evolution, CO₂ reduction, pollutant degradation, and bacterial disinfection could bring significant research advancement in this field.

尽管金属氧化物在光催化领域提供了优异的特性，但它们经常遭受电荷载流子复合以及有限的可见响应的影响，这实际上降低了电荷动力学过程并最终降低了光催化输出。缺陷工程是制造缺陷并改变主体的几何结构和化学环境的复杂技术。本研究提供了基于主体晶格尺寸对金属氧化物缺陷分类的最新进展的全面概述。准确地介绍了通过0D（点），1D（线），2D（平面）和3D（体积）缺陷对金属氧化物进行的表面改性及其后续机理以及对光催化性能的影响。₂，ZnO，Bi ₂ O ₃，Fe ₂ O ₄等）通过不同的调整和验证方法，可以显着提高其光催化活性。对缺陷工程的最佳研究不仅揭示了改变的理化特征，而且还调节了各种光氧化还原反应的电子-空穴对动力学，稳定性和活性自由基的产生。原子的改变以及电子结构的改变使光催化剂材料具有不同的光学特性，吸附特性以及改进的载流子转移以及隔离率。因此，针对各种应用（例如H _2）的富缺陷金属氧化物光催化基团的系统探索的发展，CO _2的减少，污染物的降解和细菌消毒可以在该领域带来重要的研究进展。