Fabrication of vertically aligned diamond whiskers from highly boron-doped diamond by oxygen plasma etching.

Conductive diamond whiskers were fabricated by maskless oxygen plasma etching on highly boron-doped diamond substrates. The effects of the etching conditions and the boron concentration in diamond on the whisker morphology and overall substrate coverage were investigated. High boron-doping levels (greater than 8.4 × 10(20) cm(-3)) are crucial for the formation of the nanosized, densely packed whiskers with diameter of ca. 20 nm, length of ca. 200 nm, and density of ca. 3.8 × 10(10) cm(-2) under optimal oxygen plasma etching conditions (10 min at a chamber pressure of 20 Pa). Confocal Raman mapping and scanning electron microscopy illustrate that the boron distribution in the diamond surface region is consistent with the distribution of whisker sites. The boron dopant atoms in the diamond appear to lead to the initial fine column formation. This simple method could provide a facile, cost-effective means for the preparation of conductive nanostructured diamond materials for electrochemical applications as well as electron emission devices.

Preparation and characterization of self-cleaning glass for vehicle with niobia nanosheets.

Self-cleaning glasses were prepared by coating niobia nanosheets and investigated on the performance. The coated glass heated at >450 degrees C had very low turbidity, high hardness, and excellent adhesion properties. Niobia nanosheets ([Nb(3)O(8)](-)) reacted with sodium ions (Na(+)) diffused from the glass into the films to form a crystalline phase of NaNb(3)O(8) and this phase was converted to NaNbO(3) at >450 degrees C. The films exhibited photoinduced hydrophilicity under UV irradiation but low photocatalytic oxidation activity. Excellent self-cleaning ability of the niobia nanosheet coated glass was confirmed by the Taber abrasion test, which is thought to be a candidate as self-cleaning glasses for vehicles.