TY - JOUR
T1 - Effects of ZrO2 sol concentration on microstructure and electrical properties of ZrO2-Al2O3 dielectrics formed on Al foils
AU - Zhang, Kaiqiang
AU - Park, Sang Shik
N1 - Publisher Copyright:
© 2018 Elsevier B.V.
PY - 2018/5/25
Y1 - 2018/5/25
N2 - The effects of ZrO2 sol concentration on the microstructure and electrical properties of ZrO2-Al2O3 dielectrics on etched Al foils are studied. The experiment is carried out by coating the surface of etched Al foils with ZrO2 sol with a series of concentrations and anodizing in the 2-methyl-1,3-propanediol (MPD)-boric acid electrolyte at 700, 800, and 900 V. The increase in the thickness of the ZrO2-coated layer with increasing ZrO2 sol concentration causes a reduction in the total thickness of dielectrics. The tetragonal-to-monoclinic ZrO2 phase change can be induced by anodization and the increase in the crystalline size of tetragonal ZrO2. The Zr-Al-O composite layer after anodization exhibits a microstructure that is a combination of the microstructures of separated high-permittivity crystalline ZrO2 and amorphous high-resistivity Al2O3. The optimal ZrO2 sol concentration is 1.3 M, and the specific capacitances increased by 38% for 700 V, 40% for 800 V, and 66% for 900 V compared with those of non-coated samples.
AB - The effects of ZrO2 sol concentration on the microstructure and electrical properties of ZrO2-Al2O3 dielectrics on etched Al foils are studied. The experiment is carried out by coating the surface of etched Al foils with ZrO2 sol with a series of concentrations and anodizing in the 2-methyl-1,3-propanediol (MPD)-boric acid electrolyte at 700, 800, and 900 V. The increase in the thickness of the ZrO2-coated layer with increasing ZrO2 sol concentration causes a reduction in the total thickness of dielectrics. The tetragonal-to-monoclinic ZrO2 phase change can be induced by anodization and the increase in the crystalline size of tetragonal ZrO2. The Zr-Al-O composite layer after anodization exhibits a microstructure that is a combination of the microstructures of separated high-permittivity crystalline ZrO2 and amorphous high-resistivity Al2O3. The optimal ZrO2 sol concentration is 1.3 M, and the specific capacitances increased by 38% for 700 V, 40% for 800 V, and 66% for 900 V compared with those of non-coated samples.
KW - Specific capacitance
KW - Withstanding voltage
KW - Zr-Al-O composite layer
KW - ZrO sol
KW - ZrO transformation
UR - http://www.scopus.com/inward/record.url?scp=85042869151&partnerID=8YFLogxK
U2 - 10.1016/j.surfcoat.2018.02.106
DO - 10.1016/j.surfcoat.2018.02.106
M3 - Article
AN - SCOPUS:85042869151
SN - 0257-8972
VL - 342
SP - 159
EP - 166
JO - Surface and Coatings Technology
JF - Surface and Coatings Technology
ER -