Gas encapsulation technology for large volume press

Abstract For samples in the gaseous state at room temperature and ambient pressure, mature technology has been developed to encapsulate them in a diamond anvil cell (DAC). However, the large volume press (LVP) can only treat samples with starting materials in solid or liquid form. We have achieved stable encapsulation and reaction treatment of carbon dioxide in a centimeter sized sample chamber for a long time (over 10 min) under conditions of temperature higher than 1200 °C and pressure over 5 GPa through the use of integrated low-temperature freezing and rapid compression sealing method for LVP cell assemblies. This technology can also be applied to the packaging of other gaseous or liquid samples, such as ammonia, sulfur dioxide, water, etc. in LVP devices.