The two main dry lubricants are graphite and molybdenum disulfide. They offer lubrication at temperatures higher than liquid and oil-based lubricants operate. Dry lubricants are often used in applications such as locks or dry lubricated bearings. Such materials can operate up to 350 °C (662 °F) in oxidizing environments and even higher in reducing / non-oxidizing environments (molybdenum disulfide up to 1100 °C, 2012 °F).
Source: Wikipedia contributors, "Dry lubricant," Wikipedia, The Free Encyclopedia, https://en.wikipedia.org/w/index.php?title=Dry_lubricant&oldid=870516892 (accessed July 24, 2019).
Why can solid lubricants operate only at lower temperature in oxidizing environment than in reducing environment?