Inspired by nature, tunable wettability has attracted a lot of attention in both academia and industry. Various methods of polymer surface tailoring have been studied to control the changes in wetting behavior. Polymers with a precisely controlled wetting behavior in a specific environment are blessed with a wealth of opportunities and potential applications exploitable in biomaterial engineering. Controlled wetting behavior can be obtained by combining surface chemistry and morphology. Plasma assisted polymer surface modification technique has played a significant part to control surface chemistry and morphology, thus improving the surface wetting properties of polymers in many applications. This review focuses on plasma polymerization and investigations regarding surface chemistry, surface wettability and coating kinetics, as well as coating stability. We begin with a brief overview of plasma polymerization; this includes growth mechanisms of plasma polymerization and influence of plasma parameters. Next, surface wettability and theoretical background structures and chemistry of superhydrophobic and superhydrophilic surfaces are discussed. In this review, a summary is made of recent work on tunable wettability by tailoring surface chemistry with physical appearance (i.e. substrate texture). The formation of smart polymer coatings, which adjust their surface wettability according to outside environment, including, pH, light, electric field and temperature, is also discussed. Finally, the applications of tunable wettability and pH responsiveness of polymer coatings in real life are addressed. This review should be of interest to plasma surface science communality particularly focused controlled wettability of smart polymer surfaces.

A novel two-dimensional (2D) carbon material composed of decagonal pores, and hexagonal and quadrilateral carbon rings (DHQ-graphene) is predicted by first-principles calculations. The results show that this metastable phase material displays anisotropic mechanical properties, and its in-plane Young's modulus is comparable with that of penta-graphene. DHQ-graphene is a metallic carbon material with a much higher electronic density of states of around 0.193 eV per states per atom. Equally importantly, it is also found that the most favorable adsorption site is the bridge site in the edge shared by the six- and ten-membered rings of DHQ-graphene, which has a stronger adsorption energy for oxygen (−0.27 eV) with dispersion correction (DFT-D3). The charge transfer from a DHQ-graphene sheet to an O atom amounts to 0.834|e|, 3.35% higher than that of perfect graphene. This implies that DHQ-graphene should have a good ability to adsorb oxygen with an easily controlled adsorption structure. Interestingly, it may conceivably be synthesized by a bottom-up approach from the carbon skeleton of naphthalene (C₁₀H₈). In addition, a 3D stacked structure of this material has also been investigated. This work provides a novel strategy for constructing a corrosion-resistant material by designing a 2D structure based on high-order carbon rings.

Plasma-assisted nitrogen fixation is a promising sustainable and clean alternative to the classical Haber–Bosch process. However, the high energy consumption and low production rate of plasma-assisted nitrogen fixation limit its application. This study shows that the non-thermal (non-equilibrium) enhancement of the arc plasma significantly reduces the energy consumption of nitrogen fixation. The highest energy efficiency with high NO selectivity is observed with a low specific energy input (SEI). However, the highest production rate is reached at a high SEI. The studied process offers high NO selectivity (up to 95%) with low energy consumption (∼48 GJ per tN) at 0.1 kJ L⁻¹ SEI, which is much lower than the previously reported value of plasma-assisted atmospheric nitrogen fixation and is close to that of the Haber–Bosch process.

The proliferation of natural gas production had led to increased utilization of methane as a raw material for chemicals. The most significant bottleneck in this process is the high activation energy of methane. This paper reports the direct conversion of methane to acetylene in a novel rotating arc driven by AC electrical power. By feeding a sufficiently high concentration of CH₄ (greater than 43%) diluted in H₂ (the discharge gas) through the arc column, a low specific energy requirement (SER) of 10.2 kW h kg⁻¹ C₂H₂ was achieved. The use of hydrogen as the discharge gas strongly suppressed soot formation during the methane conversion process under high methane concentration conditions, resulting in a carbon balance of greater than 95% and a C₂H₂ selectivity of greater than 90% while maintaining a methane conversion rate of greater than 70%, depending on the conditions. The novel rotating arc enabled the elongation of the arc column itself, which controlled heat loss and improved the energy use for reaction. The ability to control the arc length based on low-current type arc generation has additional benefits for reaction enhancement. These results demonstrate that arc control, optimization of the reaction conditions, and a full understanding of reaction pathway are viable means for the energy-efficient direct conversion of methane to acetylene.