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Developing cost-effective oxygen reduction reaction (ORR) catalysts is pivotal for development of fuel cells. While Fe–N–C catalysts were proposed for ORR, Fe–B–C catalysts have not been explored. This work introduces the B-doped carbon catalysts encapsulating iron cores using CO2 as a carbon source. The Fe–B–C catalysts show enhanced ORR activity and durability due to the iron core within the graphitic layers. [ABSTRACT FROM AUTHOR]

Abstract: Inorganic salts, NaCl, KCl, CaCl2, MgCl2, FeCl2, FeSO4, FeCl3, and Fe2(SO4)3, were studied as catalysts for the degradation of hemicellulose in corn stover. FeCl3 significantly increased the hemicellulose degradation in aqueous solutions heated between 140 and 200°C with high xylose recovery and low cellulose removal, amounting to ∼90% and <10%, respectively. Hemicellulose removal increased 11-fold when the corn stover was pretreated with 0.1M FeCl3 compared to pretreatment with hot water under otherwise the same conditions, which was also 6-fold greater than pretreatment with dilute sulfuric acid at the same pH. Optimum pretreatment conditions were found where the corn stover was pretreated with 0.1M FeCl3 at 140°C for 20min. Under such conditions, 91% of hemicellulose was removed, and the recovery of monomeric and oligomeric xylose in liquid fraction achieved 89%, meanwhile, only 9% of cellulose was removed. [Copyright &y& Elsevier]

Here we demonstrate that phosphorus (P) can affect both reforming and coking of alumina-supported nickel (10 wt% Ni with respect to alumina) at 750 °C and 1 atm. The P-containing catalysts were prepared by incipient wetness co-impregnation. Compared with the P-free nickel catalyst, the reforming activity is enhanced but the coke content decreases 8-fold at Ni:P atomic ratio of 4; the latter further reduces 55-fold at a ratio of 2, without a substantial decline in the reforming activity. Phosphorus not only improves nickel dispersion but also reduces the surface acidity and facilitates CO 2 activation. At high P loadings, a portion of nickel transforms into nickel oxide during reforming. Besides tuning the reforming and coking activity, phosphorus changes the behavior of carbon crystallization. In methane pyrolysis and dry reforming, filamentous carbon occurs on the P-free catalyst but it is absent on the P-containing catalyst. Image 1 • At a Ni:P ratio of 4, the reforming activity improves but coke content reduces 8-fold. • At a Ni:P ratio of 2, coking reduces 55-fold without dramatic decline in activity. • Phosphate promotes CO 2 splitting and makes the surface more basic. • Phosphorus affects the morphology of carbon deposited. [ABSTRACT FROM AUTHOR]