Efficient plasma-assisted approach in nanostructure fabrication of tungsten

Highlights: • A plasma-assisted approach to fabricate nanostructured W was presented. • W samples with wavy, meshy and villiform structure were formed. • The structure of W can be easily controlled via adjusting irradiation parameters. One kind of helium plasma-assisted approach has been presented to fabricate nanostructured tungsten. The morphology and properties evolution of tungsten under helium plasma exposure were investigated as a function of sample temperature, helium ion energy, helium ion dose and helium ion flux. The results show that high crystalline nanostructured tungsten was achieved at 1200 °C. Wavy, meshy and villiform tungsten can be expediently obtained via varying irradiation parameters. Appropriate helium ion energy and ion flux is beneficial to the formation of tungsten with stable nanostructure. The formed nanostructured tungsten was easily oxidized to stoichiometric tungsten trioxide. The as-prepared tungsten trioxide exhibits high light absorption and excellent photoelectrochemical activity. An anodic photocurrent of 3.93 mA/cm² was achieved at 1.6 V (vs. Ag/AgCl) under illumination of a 150 W Xe lamp in 0.5 M H₂SO₄ electrolyte.