Journal of Inorganic Materials ›› 2017, Vol. 32 ›› Issue (4): 431-436.doi: 10.15541/jim20160384

• Orginal Article • Previous Articles     Next Articles

Low-temperature Preparation of Cu-containing Aluminum Phosphate Coatings on Stainless Steel and Antibacterial Properties

Dong-Wei WANG(), Ying-Hao DONG, Jie ZHOU, Ke DUAN(), Xiong LU, Jian-Xin WANG, Bo FENG, Shu-Xin QU, Jie WENG   

  1. Key Laboratory of Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031, China
  • Received:2016-06-17 Revised:2016-10-09 Online:2017-04-20 Published:2017-03-24
  • About author:WANG Dong-Wei. E-mail: wdw_swjtu@163.com
  • Supported by:
    National Natural Science Foundation of China (51372210, 51572228);Ph.D Program Foundation of MOE (20130184110023);Basic Applied Research Program of Sichuan Province (2016JY0011)

Abstract:

Aluminum phosphate coatings containing different levels of Cu2+ ions (Cu/Al molar ratio: 0.025, 0.05, 0.1) were prepared on 316-stainless steel based on the curing reaction of monoaluminium phosphate (MAP). The curing behaviors of the starting materials and phase compositions of the cured products were studied by differential scanning calorimetry and X-ray diffraction, respectively. Results indicate that the copper-free MAP cures at ≤250℃ to form 3 major phases: AlH2P3O10·2H2O, AlPO4, and Al8H12(P2O7)9. When Cu2+ ions are introduced into the MAP, an additional phase of Cu2P2O7 appears in the cured product. E. coli was inoculated on the surfaces of coatings to evaluate their antibacterial properties. After co-culture with E. Coli for 12 h, all Cu2+-containing coatings exhibit antibacterial effect and show a positive association between Cu2+ content and antibacterial activity. After co-culture for 24 h, no viable bacteria remain on any Cu2+-containing coating. The addition of ethylenediaminetetraacetic acid to the culture medium substantially inhibits the antibacterial activities of all coatings, confirming that the antibacterial effect is attributed to the release of Cu2+ ions from coatings. Pull-out tests show that the bonding strengths of the coatings range between 14.5-18.1 MPa. Potentiodyanmic polarization indicates that the coatings reduce the corrosion current density of the stainless steel substrate by approximately two orders of magnitude.

Key words: copper, aluminum phosphate, coating, antibacterial

CLC Number: 

  • TQ174