Polymers used for the exteriors of spacecraft are always exposed to risks such as atomic oxygen (AO) or electrostatic discharge (ESD) degradation. In this work, an Al x Ti y O/NiCr coating with excellent mechanical stability, AO durability, and electrostatic dissipative properties was deposited via ion implantation (IIP), filter cathode vacuum arc (FCVA), and high-power impulse magnetron sputtering (HiPIMS) on a flexible Kapton substrate. Scratch and cycle folding tests indicated good adhesion and toughness of the Al x Ti y O/NiCr-coated Kapton, which were due to the gradient structure fabricated by the multitechnology combination. AO exposure tests demonstrated an extremely low erosion yield (E y = 5.15 × 10–26 cm3 atom–1) of the Al x Ti y O/NiCr-coated Kapton, only 1.72% of that observed for pristine Kapton. Moreover, Rutherford backscattering spectrometry (RBS) and Kelvin probe force microscopy (KPFM) results showed that the Al x Ti y O/NiCr-coated Kapton has elevated surface electrostatic dissipative properties and sufficient conductivity. The multitechnology combination offers great flexibility for customizing the gradient structure to realize a comprehensive performance improvement. In addition, such a coating has great prospects for aerospace applications.

The ionoluminescence (IL) spectra of a ZnO single crystal irradiated with 2.5 MeV H+ ions reveal that its intensity decreases with increasing the ion fluence, which indicates that the concentration of luminescence centers decreases with irradiation. The Gaussian decomposition results of the ZnO IL spectrum with a fluence of 1.77×1011 ions/cm2 show that the spectrum is a superposition of energy levels centered at 1.75 eV, 2.10 eV, 3.12 eV and 3.20 eV. The four peaks are associated with electronic transitions from CB to VZn, CB to Oi, Zni to VB and the decay of self-trapped excitons, respectively. The results of single-exponential fitting demonstrate that different luminescent centers have different radiation resistance, which may explain why the emission decreases more slowly in the NBE band than in the DBE band. The agglomeration of larger point clusters accounts for the decrease in the concentration of luminescence centers and the increase in the concentration of non-luminescence centers, which indicates that the defect clusters induced by ion implantation act as nonradiative recombination centers and suppress light emission. The results of the photoluminescence spectra of a virgin ZnO single crystal and a ZnO single crystal irradiated with a fluence of 3.4×1014 ions/cm2 show that compared with the virgin ZnO, the emission intensity of irradiated ZnO decreases by nearly two orders of magnitude, which demonstrates that the irradiation effect reduces radiative recombination and enhances nonradiative recombination. The conclusions of photoluminescence are consistent with the IL results.

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