From Structure to Function: Structure-Property Correlation of Layered Double Hydroxide for Persulfate Activation

The widespread contamination of water by persistent organic pollutants poses a serious threat to both the environment and public health. Sulfate radical-based advanced oxidation processes (SR-AOPs) have attracted considerable interest due to their strong oxidative power and operational adaptability. Central to these technologies is the catalytic activation of persulfate, which drives the development of efficient and stable catalysts. Among various materials, layered double hydroxides (LDHs) stand out as highly promising candidates, owing to their tunable layered structure, high surface area, and compositional flexibility. This review systematically summarizes the use of LDH-based catalysts for persulfate activation in degrading diverse organic contaminants. It further clarifies the fundamental structure–activity relationships that determine catalytic performance, covering key strategies such as electronic structure modulation via doping and defect engineering, interlayer confinement effects, and synergistic interactions among multiple metallic elements. Future research should prioritize the rational design of novel LDH composites with improved stability and selectivity, a deeper mechanistic understanding under environmentally relevant conditions, and the expansion of practical applications toward integrated treatment systems that combine effective pollutant removal with resource recovery. Progress in these areas will be vital for advancing sustainable and efficient SR-AOPs.