Investigating the feasibility of energy harvesting using material work functions

Electronic devices, with low power demand, can be energized using vibration energy harvesters which gather and transform energy from mechanical vibrations. This investigation looks at the feasibility of a method of energy harvesting from mechanical vibrations using the naturally occurring charging phenomenon within a system of two bodies which possess different work functions. In this work, a brief review of similar technologies, namely piezoelectric, electromagnetic and electrostatic energy harvesters is first given. This is followed by the development of a theoretical model and an investigation of different Work Function Energy Harvester (WFEH) operation modes, with conclusions on a possible optimum mode of operation. The design of an experiment to test the developed theory is then presented followed by some preliminary results. Generally it is found that a WFEH has potential for use in energy harvesting applications with the possibility of giving equal or better output power when compared to traditional electrostatic harvesters.