使用2,4-二羟基苯甲酸(DHBA)辅助控制合成出具有不同形貌(棒状与片状)的碱式碳酸铈.在水热阶段,碱式碳酸铈的形貌可以通过DHBA的量进行调控.当DHBA为3.5 mmol时,得到棒状碱式碳酸铈,然而增加DHBA的量至5.0 mmol时,可形成片状碱式碳酸铈.棒状与片状fcc-CeO2(面心立方二氧化铈)可成功地通过相应的焙烧处理获得.所得二氧化铈均有较大的比表面积(＞60 m2· g-1),然而与片状二氧化铈相比,棒状二氧化铈有更高的氧化还原能力与更多的酸量.棒状二氧化铈用于NH3-SCR时有着更好的催化活性.%Different morphologies (rod-like and sheet-like) of CeOHCO3 were controllably synthesized by using 2,4-dihydroxybenzonic acid (DHBA) as auxiliary.During the hydrothermal process,the morphologies of CeOHCO3 were controlled by adding different amount of DHBA.When the amount of DHBA was 3.5 mmol,rod-like CeOHCO3 was synthesized,while by increasing the amount of DHBA to 5.0 mmol,the sheet-like CeOHCO3 was relatively generated.Then the rod-like and sheet-like fcc-CeO2 (face-centered cubic-CeO2) were successfully obtained by the subsequent calcination procedure.The resulted CeO2 affords large surface area (＞ 60 m2· g-1),while the rod-like CeO2 exhibits higher redox ability and more acid amount compared to those of sheet-like CeO2.In addition,the rod-like CeO2 exhibits better catalytic activity in NH3-SCR.
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