A Novel Method of Synthesizing Boron‐doped Carbon Catalysts

Abstract

Boron‐doped carbon catalysts are prepared by a novel method combining hot filament chemical vapor deposition technique with high temperature annealing treatment. Nano‐boron powders are coated by thin diamond layers and then the coated nano‐boron powders are annealed for different times at 1,300 °C in vacuum. The morphology, microstructure, and chemical bonding states of the synthetized materials have been investigated by scanning electron microscope (SEM), X‐ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FT‐IR), and X‐ray photoelectron spectroscopy (XPS), respectively. The results indicate that boron atoms have diffused into the carbon lattice and the content of doping boron rises gradually with the increase of annealing time. The characteristic signal of the B‐C bond will vanish and of the signal B4C will appear, if the annealing time is too long. The experimental results of rotating disk electrode (RDE) voltammetry illustrate that the catalyst obtained after annealing for 2 h has the highest electrocatalytic oxygen reduction reaction (ORR) activity. The response current characterized by chronoamperometry exhibits that the deposits with a higher catalytic activity have a poorer stability and methanol tolerance.

Progress of Nonmetallic Electrocatalysts for Oxygen Reduction Reactions

“…However, the ORR catalytic activity of BCNTs was lower than that of commercial Pt/C catalysts and even lower than that of NCNTs catalysts under acidic conditions. Suo et al made boron-doped carbon catalysts by chemical vapor deposition and high-temperature annealing [68]. As shown in Figure 8b,c, FTIR and XPS showed that, after annealing for 2 h, the boron content was directly proportional to the Compared to those of NCNTs catalysts, the stability and CO toxicity resistance of BCNTs catalysts were also good.…”

“…( c ) Survey scanning XPS spectra of the deposits annealed for (i) 1, (ii) 2 and (iii) 3 h, respectively. High-resolution XPS spectra for the B 1 s peak of the deposits annealed for (iv) 1 and (v) 2 h, respectively [ 68 ].…”

“…(b) FT-IR spectra of the deposits for (i) un-annealing and annealing for (ii) 1, (iii) 2, (iv) 3 and (v) 4 h at 1300 • C. (c) Surveyscanning XPS spectra of the deposits annealed for (i) 1, (ii) 2 and (iii) 3 h, respectively. High-resolution XPS spectra for the B 1 s peak of the deposits annealed for (iv) 1 and (v) 2 h, respectively[68].…”