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CeO 2 modified commercial SCR (selective catalytic reduction) catalysts with different CeO 2 content were prepared and researched for synergistic mercury removal from coal combustion flue gas in this study. The characterization analyses on the catalysts indicated that the introduction of CeO 2 increased the surface area, the dispersity of the metal oxides on the TiO 2 support and the redox behavior of the catalyst, which was beneficial to the catalytic activity. The experimental results confirmed that the CeO 2 loading improved the catalytic efficiencies over the commercial SCR catalyst. The catalyst with a CeO 2 content of 4% displayed the optimal performance for NO and synergistic Hg 0 removal, of which the NO conversion and Hg 0 removal efficiency reached 90.5% and 78.2%, respectively, at 300 °C in simulated coal-fired flue gas. The Hg 0 removal activity, the independence of Hg 0 removal from HCl concentration and the effects of SO 2 , NO and NH 3 on Hg 0 removal efficiency all became positive over the modified catalyst compared to over the raw one, which was mainly due to the sufficient chemisorbed oxygen derived from the synergy of V 2 O 5 and CeO 2 and the redox transformation between Ce 3+ and Ce 4+ on the catalyst surface. The CeO 2 modification generated a significant enhancement on the catalytic performance and made the commercial SCR catalyst more suitable to be employed for NO and synergistic mercury removal in a coal combustion power plant., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

TeO-B 2 O 3 -BaO glasses with different compositions were prepared by the conventional melt-quenching technique. The spectral properties of Tm 3+ /Ho 3+ co-doped TeO-B 2 O 3 -BaO glasses with different doping concentrations were studied. In order to analyze the spectroscopic properties in detail, the Judd-Ofelt intensity parameters, spontaneous radiative probabilities, branching ratios, absorption and emission cross-sections, and gain coefficient spectra were calculated using Judd-Ofelt and McCumber theory based on the absorption and emission spectra. Meanwhile, the optimal doping concentration was determined as Tm 2 O 3 : 1.0 mol% and Ho 2 O 3 : 1.0 mol%. The results show that Tm 3+ /Ho 3+ co-doped TeO-B 2 O 3 -BaO glass is an ideal mid-infrared laser gain medium., Competing Interests: The authors declare no conflicts of interest., (This journal is © The Royal Society of Chemistry.)