Effect of hydrogen desorption kinetics on the thermionic emission from hydrogen-terminated diamond films

Thermionic electron emission (TE) from functionalised diamond surfaces can be used in thermionic energy converters to perform a direct energy conversion from heat to electricity. This type of devices have applications on renewable energy or in space exploration by using them as a power plant for satellites and space shuttles. A stable surface functionalisation that leads to a low work function (WF) is essential for TE to occur. And although diamond is a promising material for this technology, creating a surface that is stable at high temperatures has proven to be difficult. Moreover, the Richardson equation, used to describe the TE from a surface fails to explain the behaviour of the diamond surfaces tested so far. In this poster, we present a new thermionic emission model that accounts for the surface termination changes and we apply it to hydrogen terminated diamond surface as it is the most popular diamond termination.