Bismuth Oxychloride Nanoplatelets by Breakdown Anodization

Abstract

Herein, the synthesis of BiOCl nanoplatelets of various dimensions is demonstrated. These materials were prepared by anodic oxidation of Bi ingots in diluted HCl under dielectric breakdown conditions, triggered by a sufficiently high anodic field. Additionally, it is shown that the use of several other common diluted acids (HNO 3 , H 2 SO 4 , lactic acid) resulted in the formation of various different nanostructures. The addition of NH 4 F to the acidic electrolytes accelerated the growth rate resulting in bismuth‐based nanostructures with comparably smaller dimensions and an enormous volume expansion observed during the growth. On the other hand, the addition of lactic acid to the acidic electrolytes decelerated the oxide growth rate. The resulting nanostructures were characterized using SEM, XRD and TEM. BiOCl nanoplatelets received by anodization in 1 M HCl were successfully employed for the photocatalytic decomposition of methylene blue dye and showed a superior performance compared to commercially available BiOCl powder with a similar crystalline structure, confirming its potential as a visible light photocatalyst.

Synthesis of Bi2O3-MnO2 Nanocomposite Electrode for Wide-Potential Window High Performance Supercapacitor

“…The surface morphology of the as-prepared Bi 2 O 3 -MnO 2 nanocomposite was initially analyzed using SEM images like that shown in Figure 3a, which highlights the fine nanoplatelet-like structures fused to each other [34]. A magnified image of this morphology shows that these platelets exist in a cubic form (Figure 3a insert).…”

Controlled synthesis of tungsten trioxide with globular clusters constructed of nanoplates by rapid breakdown anodization

“…Compared with conventional anodization, the so-called RBA method owns a series of unique characteristics such as high-speed, large-scale production, low cost, and feasibility of obtaining nanomaterials in powder form with tunable structures [15,16], which has a wide range of applications in many fields. However, although continuous progresses have been made in the preparation and modification of TiO 2 [17][18][19] or other valve metal oxide nanomaterials via RBA [20][21][22], there are few reports concerning the RBA synthesis of WO 3 with specific nanostructures. The rapid electrochemical oxidation process in highly corrosive medium under dielectric breakdown conditions inevitably leads to insufficient crystal growth, leading to WO 3 nanopowder with low crystallinity and irregular morphology.…”

Addition of Organic Acids during PEO of Titanium in Alkaline Solution

“…Its main use in the anodization field is related to the synthesis of nanotubular geometries [25,26], where the organic molecule acts as an anodic breakdown retardant, favoring the nanotubes' thickness and growth rate. However, as lactates tend to be preferentially adsorbed on the electrode surface during the anodic half-cycle, the decrease in the overall charge transfer reaction, responsible for metal oxidation, determines a lower film growth [27]. Despite the use of the above cited additives, in processes involving valve metals such as Al or Mg, to the best of our knowledge, no report regarding PEO on Ti with the following chemicals has been reported.…”