In this study, we used an argon-based round atmospheric-pressure plasma jet (APPJ) for enhancing wound healing in streptozotocin (STZ) induced diabetic rats. The APPJ was characterized by optical emission spectroscopy. We induced Type 1 and Type 2 diabetes in rats with different amounts of STZ combined with normal and high-fat diets, respectively. The wound area ratio of all the plasma-treated normal and diabetic groups was greatly reduced (up to 30%) compared with that of the untreated groups during healing. Histological analysis revealed faster re-epithelialization, collagen deposition, less inflammation, and a complete skin structure in the plasma-treated groups was found as compared with the untreated control groups. In addition, the new blood vessels of plasma-treated tissues decreased more than untreated tissues in the middle (Day 14) and late (Day 21) stages of wound healing. The plasma-treated wounds demonstrated more transforming growth factor beta (TGF-β) expression in the early stage (Day 7), whereas they decreased in the middle and late stages of wound healing. The levels of superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) increased after plasma treatment. In addition, plasma-treated water had a higher concentration of hydrogen peroxide, nitrite and nitrate when the plasma treatment time was longer. In summary, the proposed argon APPJ based on the current study could be a potential tool for treating diabetic wounds.

Heteroatom-doped graphene quantum dots (GQDs) can change the optical, chemical, electrical, and optoelectrical properties of materials and diversify their functions. GQDs can be used in a wide range of applications, including in fluorescent agents, light-emitting diodes, bioimaging, solar cells, optoelectronic detectors, photocatalysts, etc. In this article, we describe the synthesis of S and N co-doped graphene oxide quantum dots (S,N-GOQDs) with stable electroluminescence, photoluminescence, and photocatalytic properties and their optoelectrical applications as an emitter of a light-emitting diode device in electro-optical energy conversion and as a photocatalyst for hydrogen evolution in photo-chemical energy conversion. The synthesized S,N-GOQDs show a high yield and excitation-independent emission. The maximum excitation wavelength and emission wavelength are 371 and 447 nm, respectively; the quantum yield is 61% when excited at 371 nm; and the emission half-width is 40 nm. A bright blue emission with a luminance exceeding 1341 cd m⁻² was achieved at 6 V, thus proving the potential of S,N-GOQDs as an emitter in electroluminescence applications. For photocatalytic hydrogen evolution, the system consists of a 0.1 mg mL⁻¹ catalyst in pure water or TEA (1.43 M) + 80% EtOH aqueous solution. In pure water, high reaction rates of 3.001 mol h⁻¹ g⁻¹ were obtained under direct sunlight. In the TEA (1.43 M) + 80% EtOH aqueous solution, an unprecedented efficiency of 71 mmol h⁻¹ g⁻¹ and 6.138 mol h⁻¹ g⁻¹ was obtained under a 500 W Xe lamp and direct sunlight, respectively.