Dynamic gas template method derived thin-layer graphitic carbon nitride nanosheets for efficient 2,4-dichlorophenoxyacetic acid photodegradation and mechanism insight.

The extensive application of 2,4-dichlorophenoxyacetic acid (2,4-D, CHClO) as a herbicide has resulted in the significant environmental contamination. This pervasive pollution poses serious health risks to humans. Semiconductor photocatalytic technology represents a highly effective approach to addressing urgent environmental crisis. Herein, thin-layer g-CN nanosheets were synthesized using NHCl as a dynamic gas template. Among all synthesized materials, the thin-layer g-CN (2.5N-MCN) exhibited a degradation rate constant (k) for 2,4-D that was 3.05 times higher than that of pristine g-CN (MCN). 2.5N-MCN exhibits continuous lamellar nanostructures, the highest specific surface area (S), and superior electrochemical properties among all samples. Moreover, the hydroxyl radical (·OH) was identified as the predominant reactive species in the photocatalytic degradation process. Subsequently, the degradation pathway of 2,4-D was deduced from the identified intermediates. And the process of photocatalytic degradation 2,4-D proceeded without significant elevated in toxicity levels by the TEST software. Then, the pH and fulvic acid influence experiment were also studied. Nevertheless, the photocatalytic degradation efficiency of 2.5N-MCN toward 2,4-D exhibited a moderate decline after four cycles. This research provided insights into the improving the photocatalytic efficiency of organic pollutant degradation through efficient solar conversion materials.