A carbon nitride
(C3N4) nanomaterial
has
superior mechanical, thermal, and tribological properties, which make
them attractive for various applications, including corrosion-resistant
coatings. In this research, newly synthesized C3N4nanocapsules with different concentrations (0.5, 1.0, and 2.0 wt
%) of ZnO as a dopant were incorporated into the NiP coating using
an electroless deposition technique. The nanocomposite coatings either
ZnO-doped (NiP-C3N4/ZnO) or undoped (NiP-C3N4) were heat-treated at 400 °C for 1 h. The
as-plated and heat-treated (HT) nanocomposite coatings were characterized
by their morphology, phases, roughness, wettability, hardness, corrosion
protection, and antibacterial properties. The results indicated that
the microhardness of as-plated and heat-treated nanocomposite coatings
was significantly improved after the incorporation of 0.5 wt % ZnO-doped
C3N4nanocapsules. The outcomes of electrochemical
studies revealed that the corrosion resistance of the HT coatings
is higher than the corresponding as-plated ones. The highest corrosion
resistance is achieved on the heat-treated NiP-C3N4/1.0 wt % ZnO coatings. Although the presence of ZnO in the
C3N4nanocapsules increased its surface area
and porosity, the C3N4/ZnO nanocapsules prevented
localized corrosion by filling the microdefects and pores of the NiP
matrix. Furthermore, the colony-counting method used to evaluate the
antibacterial behavior of the different coatings demonstrated superior
antibacterial properties, namely, after heat treatment. Therefore,
the novel perspective C3N4/ZnO nanocapsules
can be utilized as a reinforcement nanomaterial in improving the mechanical
and anticorrosion performance of NiP coatings in chloride media, together
with providing superior antibacterial properties.