Composite materials for next generation plasma energy systems

The investigation of graphene and porous silicon (PS) composite materials for low work function PETE (photon-enhanced thermionic emission for solar concentrator systems) energy systems synthesis is performed in this article. These two types of materials are suggested for further development and study due to noteworthy physical effects taking place in the aforementioned structures. The nature of low-work function phenomenon is interpreted as related to the influence of functionalization and synthesis parameters on the surface structure of composite materials. The Raman spectroscopy technique is used to characterize porous silicon based nanostructured composite layers (PS/Ag). The interpretation of PS/Ag Raman spectra is suggested. The significant decrease in the effective electron work function to a value of 1 eV is registered in a perforated graphene-covered nickel anode intercalated with Cs atoms. SEM X-ray microanalysis of the anode surface is performed, the interpretation of the anode work function lowering effect is proposed. (paper)