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Highlights: [•] NO removal is enhanced on the F-doped CeO2-TiO2 catalysts for low-temperature SCR. [•] F doping can increase oxygen vacancies on the catalysts. [•] O2 − produced on the oxygen vacancies by F doping are responsible for the high catalytic activity. [•] Addition of F also enhances ad-NO species and reaction intermediates (NO2 −, NO3 −). [Copyright &y& Elsevier]

Abstract: Y-doped La0.7Sr0.3CrO3−δ is a promising anode catalyst for solid oxygen fuel cell (SOFC). The performances of chemical and physical are measured by SEM, XRD and FT-IR. The conductivities of catalyst are measured by DC four-probe method in 20% H2S–N2, 3% H2–N2 and air from 573K to 1173K, respectively. The results show that Y-doped La0.7Sr0.3CrO3−δ powders have perfect perovskite phase structure with no extra peaks and exhibit good chemical compatibility with Ce0.8Sm0.2O1.9 (as electrolyte) in air. Through XRD and FT-IR analysis no sulfur-containing species is detected after exposure to the 20% H2S at 1173K for 5h. Meanwhile, Y-doped La0.7Sr0.3CrO3−δ shows that the highest conductivity is 0.21S/cm at 1173K in H2S. The open circuit voltages are 0.85V at 1173K in H2S and 1.04V at 823K in H2. The maximal power densities are 12.4mW/cm2 in H2S and 1.59W/cm2 in H2 for cells comprising Y-doped La0.7Sr0.3CrO3−δ –Sm0.2Ce0.8O1.9/Sm0.2Ce0.8O1.9/Ag. [Copyright &y& Elsevier]

Highlights: [•] The incorporation of AGO changes the chemistry and microstructure of MOF. [•] The composites result in unique texture and modified chemical environment. [•] The synergistic effect created in the composites is useful for CO2 adsorption. [•] The composites involved by GO or AGO show better anti-moisture performance. [ABSTRACT FROM AUTHOR]

Abstract: A series of chromium-ceria doped on TiO2-pillared clay nanocomposites catalysts with various Cr/Ce ratios were investigated in the oxidation of NO. This study aimed to not only synthesize the CrCe/TiO2-PILC nanocomposites, but also figure out the promotion effect of Ce in the oxidation process and the interaction between chromium and ceria on the surface of TiO2-PILC. The samples were characterized by XRD, SEM, TEM, XPS and H2-TPR methods. The best catalyst Cr(1)Ce(0.25)/TiO2-pillared clay yielded 69% NO to NO2 conversion at 350°C (in the condition of GHSV=35,400h−1). With the content of ceria increasing, the NO conversion increased significantly while when the Cr/Ce equaled 1:1, the activity decreased. The chromium oxides were well dispersed on the surface of the support. Analysis of XPS indicated that the addition of ceria oxides could promote the formation of chemisorbed oxygen and raise the quantivalency of Cr. The powerful electron withdrawing ability of Ce made the electron density around Ti atoms decrease. The result showed that CeO x enhanced the metal–support interaction. H2-TPR indicated that the proper addition of CeO x increased the reducible phase that was beneficial to the reaction. Moreover, the catalysts showed a good resistance to SO2 and H2O. When SO2 and H2O were added in the feed gas, the catalytic activity decreased but when removed, the activity recovered. The deactivation was not totally irreversible. [Copyright &y& Elsevier]

Abstract: The aim of this paper is to examine the feasibility of Y0.9Sr0.1Cr1−x Fe x O3−δ for potential use as anode materials in solid oxide fuel cells (SOFCs) fed with fuel gas containing H2S, as well as other electrochemical devise. Y0.9Sr0.1Cr1−x Fe x O3−δ (x =0.1, 0.3, 0.5) were synthesized by gel combustion method and had single-phase orthorhombic perovskite structure. These materials were all stable in reducing atmosphere (10%, v/v H2/N2) up to 800°C. By the comparison of the O 1s peaks assigned to Y0.9Sr0.1Cr1−x Fe x O3−δ before and after reduction in H2/N2, lower content of lattice oxygen and higher content of adsorbed oxygen were observed for Y0.9Sr0.1Cr0.9Fe0.1O3−δ , while others appeared opposite results. This phenomenon suggested that reduced Y0.9Sr0.1Cr0.9Fe0.1O3−δ could capture oxygen when exposure to air, which is essential for anode materials. Moreover, Y0.9Sr0.1Cr0.9Fe0.1O3−δ maintained good chemical stability under H2S-containing atmosphere through XRD and FT-IR analysis. So Y0.9Sr0.1Cr0.9Fe0.1O3−δ was suggested as a promising anode material for SOFCs fed with fuel gas containing H2S. [Copyright &y& Elsevier]

Abstract: The novel carbon dioxide (CO2) adsorbents with high capture efficiency were prepared through impregnating TiO2 nanotubes (TiNT) with four kinds of amines, namely monoethanolamine (MEA), ethylenediamine (EDA), triethylenetetramine (TETA) and tetraethylenepentamine (TEPA), respectively. The samples were characterized by thermogravimetric analysis, low temperature N2 adsorption and transmission electron microscopy. CO2 capture was investigated in a dynamic packed column. The TEPA-loaded sample showed a better adsorption capacity due to its higher amino-groups content. In condition, TiNT-TEPA-69 shows the highest CO2 adsorption capacity among the four TEPA-loaded samples, approximately 4.37mmol/g at 60°C. The adsorption capacity was enhanced to 5.24mmol/g under moisture conditions. TiNT-TEPA-69 was selected as adsorbent to study the adsorption/desorption behavior in the absence of moisture and in the presence of moisture. While the former is fairly stable after 5 adsorption/desorption cycles, the latter decreases dramatically. [Copyright &y& Elsevier]