Light-induced nanostructured thermionic energy converters: The effect of cathode-anode gap on the output current

Nanostructured thermionic energy converters may offer substantial advantages over traditional devices by reducing system complexity and requirements. However, they still face similar fundamental challenges, such as anode collection efficiency and the space charge effect, which have limited their performance to date. Here, we investigate a carbon nanotube-based thermionic converter, demonstrating that its output current is enhanced substantially by making the cathode-anode gap smaller, presumably due to the improved collection efficiency and reduction of space charge.