We pioneer the use of CO₂ nanobubbles (NCHM) for adjusting the physiochemical properties of activated carbon fibers (ACF) to improve the microextraction performance of heavy metal ions. We first synthesized NCHM-loaded ACF (N-ACF) through the gas-phase using a mixture of CO₂ and H₂O. To explore another green alternative, F-ACF was also prepared by the impregnation of formic acid. Physiochemical analyses indicated that N-ACF experienced minimized surface area decrement (16.60 % better than F-ACF), but increased surface functional moieties (25.54 wt% better than ACF). Herein, we successfully modulated abundant but abandoned macropores into micropores by NCHM with a median size of 147 nm and the concentration of 3.08 × 10¹⁰ particle ml⁻¹. The microextraction performance of Pb(II) and Cd(II) under the simulated river environment was in the order of N-ACF (Q_max for Pb(II): 4.963 and Cd(II): 4.677) > ACF (4.632, 4.448) > F-ACF (4.447, 4.357) with revealed characteristics of monolayer adsorption, feasible, spontaneous and endothermic in nature. Ultimately, it can be postulated that NCHM could be a promising method in which case physiochemical properties of an absorbent affect the overall microextraction performance.

我们率先使用CO ₂纳米气泡（NCHM）来调节活性碳纤维（ACF）的理化性质，以改善重金属离子的微萃取性能。我们首先使用CO ₂和H ₂ O的混合物通过气相合成了负载NCHM的ACF（N-ACF）。为探索另一种绿色替代方法，还通过浸渍甲酸制备了F-ACF。理化分析表明，N-ACF的表面积减少最小（比F-ACF好16.60％），但表面功能部分增加（比ACF好25.54 wt％）。在这里，我们通过NCHM成功地将丰富但被遗弃的大孔转化为微孔，中值粒径为147 nm，浓度为3.08×10 ¹⁰毫升^-1。在模拟河流环境下，Pb（II）和Cd（II）的微萃取性能为N-ACF顺序（Pb（II）的Q _max：4.963和Cd（II）：4.677）> ACF（4.632，4.448） ）> F-ACF（4.447，4.357）具有揭示的单层吸附特性，可行，自发和吸热。最终，可以假定NCHM可能是一种有前途的方法，在这种情况下，吸收剂的物理化学性质会影响整体微萃取性能。