“…Enhancing secondary electron emission capability of the protective layer is another effective way to significantly decrease the discharge voltage. Alternatively, PDP operating voltage reduction can be achieved by changing the MgO surface morphology and crystal structure by annealing process [3] or via altering preparation conditions [4] to increase the secondary electron emission. Last but not least, PDP operating voltage reduction can be achieved by developing the composite protective layer, for example, SrO/MgO [5], MgO/Graphite-in-diamond (GiD) [6], MgO/TiO 2 [7], MgO/nano Au [8], ZnO/MgO [9] and MgO/NiO [10], in order to increase the secondary electron emission.…”