Dynamic activation of PMS by CoNi-Zn(OH)2/MnO2 micromotors for efficient degradation of phenolic pollutants

CoNi-Zn(OH)2/MnO2 micromotors with high specific surface area were synthesized by calcination, coprecipitation, hydrothermal, and ionic doping using the natural plant material ramie as a template. MnO2 in the micromotor catalyzed the H2O2 fuel to generate large amounts of O2, achieving a maximum velocity of 77.504 +/- 5.19 mu M S-1 for bubble driving. And H2O2 and peroxomonosulfate (PMS) were used as the catalytic substrates to generate hydroxyl radicals (center dot OH), superoxide radicals (O center dot-2), singlet-linear oxygen (1O2), and sulfate radicals (SO center dot-4), realizing the synergistic detection and degradation of phenolic pollutants. The high enzymelike catalytic activity and autonomous motions of CoNi-Zn(OH)2/MnO2 micromotor together resulted in the detection limits of 3.9 x 10-7 M for catechol (CC) and 4.21 x 10-7 M for hydroquinone (HQ), respectively. In addition, the degradation rates of CC and HQ by the micromotor could reach 98.0 % and 96.5 %, respectively, within 30 min under neutral conditions (pH = 7). This system provides new insights into the construction of bubble-driven tubular CoNi-Zn(OH)2/MnO2 micromotor for the efficient and sensitive detection and degradation of phenolic pollutants in water.