C 60 fullerene exhibits unique optical properties that have high potential for wide photooptical applications. To analyze the optical properties of C 60 , its excitation and emission properties were studied using UV-Vis absorption and photoluminescence (PL) spectroscopy, which were performed in various, nonpolar organic solvents such as toluene, xylene, and trichloroethylene (TCE). The C 60 solutions in toluene, xylene, and TCE displayed similar excitation bands at 625, 591, 570, 535, and 404 nm corresponding to A g → T 1u and A g → T 1g transitions. However, these bands differed from the solid C 60 observed by UV-Vis diffuse reflectance spectroscopy. The two emission band energies of C 60 solution in toluene and xylene were nearly the same (1.78 and 1.69 eV), whereas the C 60 solution in TCE was shifted to 1.72 and 1.65 eV. Because the polarity of TCE is higher than that of toluene and xylene, the PL spectrum of the C 60 solution in TCE was red-shifted. The PL spectroscopy had a better capability than UV-Vis absorbance spectroscopy to distinguish the different interactions between C 60 and the organic solvents due to their different solvent polarities.

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Plasma jet is one of the methods for surface material modification that is economically and environmentally friendly. This method can be applied in ambient pressure that makes this method more feasible. The discharge of plasma from the plasma jet can be adjusted according to the design used. Carrier gas that is used in the plasma jet system can also be adapted to the needs or appropriate to the target material. The gases that can be used are helium, argon, etc. A variant gas flow rate will also affect the plasma species and the surface material characteristics produced. Modifying a material with certain compounds can be done by passing the active gases or vapors through the carrier gas. The use of the plasma jet method possibly converts the surface material to be hydrophobic or hydrophilic characteristics. Moreover, the plasma jet technique is applicable for various materials or substrates in any dimension. This review article will discuss the parameters applied, such as various designs, carrier gas, gas flow rates, power used in the plasma jet.

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