Low-temperature chemical vapor deposition of cobalt oxide thin films from a dicobaltatetrahedrane precursor†
Cobalt oxides are a promising anode material for lightweight rechargeable lithium-ion batteries. Thus, the low temperature deposition of cobalt oxide is a key-technology for the production of flexible energy storage systems enabling novel application opportunities such as wearables. To satisfy the emerging process requirements the dicobaltatetrahedrane precursor [Co2(CO)6(η2-H–CC–nC5H11)] was investigated for the low-temperature chemical vapor deposition of cobalt oxides. Oxygen, water vapor and a combination of both were examined as possible co-reactants. In particular, wet oxygen proves to be an appropriate oxidizing agent providing dense and high purity cobalt oxide films within the examined temperature range from 130 °C to 250 °C. Film growth occurred at temperatures as low as 100 °C making this process suitable for the coating of temperature-sensitive and flexible substrates.