As a layered nano-sheet material, layered graphitic carbon nitride (g-C₃N₄) has attracted attention in multifunctional photocatalytic applications. However, g-C₃N₄ is electrochemically inert consequently hampering electrochemical applications. In this work, low-temperature nitrogen plasma processing was conducted to modify g-C₃N₄ to enhance the electrocatalytic performance in the hydrogen evolution reaction (HER). The plasma produced significant morphological and chemical changes on the surface of g-C₃N₄ via active species, and nitrogen atoms were incorporated into the surface while the bulk properties did not change. The modification improved the surface hydrophilicity and electrocatalytic HER activity, as well as excellent stability in HER after 2000 cycles. Our results revealed that plasma treatment was a promising technique to improve the HER of carbon-based layered nano-sheet materials.

Dielectric barrier discharge (DBD) plasma surface modification has certain aging effect. This article studies the aging effect of plasma (DBD) on the surface modification of carbon fibers. The test results show that plasma (DBD) treatment reduces the impurity particles on the surface of carbon fibers and makes the surface texture coarser. In addition, there is no significant change. After plasma (DBD) treatment, the content of C–O–C, C–O and C=O on the surface of carbon fibers increased from 3.20%, 7.76% and 1.64% to 7.06%, 21.50 and 6.08%, respectively. This is due to the high-energy particle bombardment of the fiber surface, which forms activated carbon atoms on the surface. The free electrons of these activated carbon atoms combine with ionized oxygen in the air. However, with the passage of time, the content of C–O–C, C–O and C=O gradually decreases to 3.31%, 8.57% and 1.77%, respectively. This is because some functional groups formed on the treated carbon fiber surface are not firmly bound, and some of these functional groups containing O₂ groups will combine with surrounding substances through irreversible chemical oxidation reactions to produce CO₂, which leaves the carbon fiber surface as a gas. The treated carbon fibers will immediately become hydrophilic, and the water contact angle decreases from 148.71° to 0°. With the passage of time, the water contact angle gradually increases to 118.16°, and the hydrophobicity recovers.

Electrical explosion, characterized by ultrafast atomization and quenching rate (dT/dt ≈ 10¹⁰–10¹² K s^–1) of the sample, is a unique approach for “one‐step” synthesis of nanomaterials. Experiments are carried out with layered graphite and Bi₂Se₃ under the action of electrical explosion in a confined reaction tube. High‐speed photography and electrophysical diagnostics are applied to characterize dynamic processes. SEM and EDS are used to characterize surface micro‐morphology of reaction products. The layered materials are first exfoliated to thin nanosheets/nanocrystals by shock waves and turbulent flow of the explosion. As the ionized explosion products (>10 000 K) contacts the sample, intense heat transfer happens, simultaneously atomizing the sample and quenching the plasmas. As a result, nanoparticles grow on the surface of thin sheets, forming “dot‐sheet” structure. The size distribution of the nanoparticles typically ranges from 10 to 100 nm, following Log‐normal distribution. The dotted graphite nanosheets gather together and form a stacked/cabbage‐like structure. By contrast, Bi₂Se₃ case accompanies with chemical reactions, causing surface corrosion and showing more possibilities: nanocrystals and nanotubes growth on different areas of the sample.

The fabrication process of modern microelectronic devices faces a significant challenge regarding the uniformity of wafer processing during plasma etching. Particularly, nonuniformity is prominent at the wafer edge due to varying electrical properties, leading to sheath bending and distorted ion trajectories. To address this issue, a wafer terminating structure known as a focus ring is employed to modify the sheath structure near the edge of the wafer and ensure uniform ion fluxes. However, the focus ring is subject to erosion caused by the plasma, making it crucial to minimize the ion energy bombarding the focus ring. In light of this, this paper investigates the impact of parameters such as the wafer-focus ring gap, focus ring height, and dielectric constant of the focus ring on the ion angle onto the wafer and the ion energy onto the focus ring. To conduct the analysis, a 2D3V particle-in-cell/Monte Carlo collision model is utilized. The study reveals the existence of horizontal electric fields with opposite directions at the wafer edge and the inner edge of the focus ring. Optimizing the ion angle onto the wafer edge can be achieved by adjusting the material and geometry of the focus ring. Furthermore, reducing the ion energy at the focus ring can be accomplished by increasing the height or decreasing the dielectric constant of the focus ring.