Dynamic and active antiscaling via scale inhibitor pre-stored superhydrophobic coating

Anti-scaling is one key problem in various industrial productions. The coating technology is the most effective protection method for metals and pipelines. As a good scale inhibitor, diethylene triamine penta(methylene phosphonic acid) (DTPMPA) generally takes effect after placement into wastewater and through discharging with water flow. In this study, a novel DTPMPA-modified superhydrophobic anodized aluminium (DSAA) coating was designed, fabricated and utilized for anti-scaling of CaCO 3 deposition. The unique anti-scaling performance on the surface of the DSAA coating originated from the gradual release of DTPMPA at the solution/coating interface, plus the effect of superhydrophobic anti-scaling. During the CaCO 3 deposition, the abundant air layer retained at the surface of the superhydrophobic DSAA coating prevented further deposition of CaCO 3 . In addition, the active DTPMPA gradually and dynamically released from the DSAA coating to the water/coating interface chelated with Ca 2+ and further stopped the possible combination between Ca 2+ and CO 3 2− . This synergistic antiscaling effect of the DSAA coating showed a wide application prospect in effective anti-scaling on various surfaces. This work provides a new way of designing and fabricating dynamic superhydrophobic coatings for anti-scaling.