One-step crushing & cladding technology and enhanced anticorrosion activity of Zn3(PO4)2@AlH2P3O10 pigment

Abstract The high acidity and crushing difficulty of aluminum tripolyphosphate (AlH 2 P 3 O 10 , ATP) have been of great attention due to directly inhibiting its anticorrosive performance. Here, one-step crushing & cladding technology is designed to achieve the modification and crush of ATP concurrently. According to electrochemical impedance spectroscopy experiment, the impedance of Zn 3 (PO 4 ) 2 @AlH 2 P 3 O 10 (ZATP) pigment is 148.94% and 133.44% higher than those of ATP and Zn 3 (PO 4 ) 2 (ZP) pigment, respectively. The enhanced corrosion resistance of ZATP pigment is mostly ascribed to the coefficient of low acidity, spacing crush and surface modification. After the modification, the pH value of ATP pigment is increased from 2.84 to 6.58, thereby reducing the metal destruction caused by acidity. Moreover, the specific surface area (S BET ) of ZATP pigment increased by 204.89% lies in the decreased particle size of the pigment significantly. Interestingly, ZP and ATP separately release active inhibitors in early and late corrosion process to form complicated chelate passive films isolating the steel panels from the aggressive electrolytes, exerting a synergistic anticorrosive effect. This technology provides an innovative thought for low-cost metal protection.