Novel carbon/carbon core/shell nanotubes (C/C-NTs) composed of well-crystallized core carbon nanotubes (CNTs) and structurally disordered carbon shells were prepared for obtaining a new type of nanotube material with high specific surface area (SSA). The disordered carbon shells were prepared by coating polyaniline (PANI) layers on the core CNTs through in situ polymerization and subsequent carbonization. Chemical activation was conducted for the C/C-NTs with KOH at 1123 K to prepare activated C/C-NTs (AC/C-NTs). Scanning electron microscopy, transmission electron microscopy (TEM), X-ray diffraction, Raman spectroscopy, and an adsorption analyzer were used to characterize the nanotube samples. The outer carbon shells thermally converted from the PANI layers are much less ordered and thus much more reactive than the CNTs. The AC/C-NTs tend to have much higher SSA than that obtained by directly activating the CNTs, and the obtained SSA for the AC/C-NTs is as high as 2924 m 2 /g, which is the highest among the existing nanotube materials. TEM shows that the hollow structure and high crystallinity of the core CNTs were well preserved during carbonization and activation. The novel AC/C-NTs may find important applications in many areas such as supercapacitors, catalyst supports, adsorption, and hydrogen storage due to their superhigh SSA and nanotubular structure. The present work provides a way for preparing other core/shell nanotube or nanowire materials with high SSA.

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A series of poisoned catalysts with various forms and contents of sodium salts (Na2SO4 and Na2S2O7) were prepared using the wet impregnation method. The influence of sodium salts poisoned catalysts on SO2 oxidation and NO reduction was investigated. The chemical and physical features of the catalysts were characterized via NH3-temperature programmed desorption (NH3-TPD), H2-temperature programmed reduction (H2-TPR), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET), X-ray diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FT-IR). The results showed that sodium salts poisoned catalysts led to a decrease in the denitration efficiency. The 3.6% Na2SO4 poisoned catalyst was the most severely deactivated with denitration efficiency of only 50.97% at 350 °C. The introduction of SO42− and S2O72− created new Brønsted acid sites, which facilitated the adsorption of NH3 and NO reduction. The sodium salts poisoned catalysts significantly increased the conversion of SO2–SO3. 3.6%Na2S2O7 poisoned catalyst had the strongest effect on SO2 oxidation and the catalyst achieved a maximum SO2–SO3-conversion of 1.44% at 410 °C. Characterization results showed sodium salts poisoned catalysts consumed the active ingredient and lowered the V4+/V5+ ratio, which suppressed catalytic performance. However, they increased the content of chemically adsorbed oxygen and the strength of V5+=O bonds, which promoted SO2 oxidation.