The results of a series of consecutive TPR profiles of fresh and aged catalysts are illustrated in Figure 1. For the fresh catalysts, all of the samples exhibit a dominate low-temperature reduction feature at ca. 65 °C (peak a)andthree small peaks denoted by b, c,anddappeared in the range of 150-400 °C. Previous investigations have
reported that palladium oxide is reduced to palladium on exposure to H2 at room temperature (22, 23). In addition, no characterization was observed below 150 °C in the TPR profiles of fresh supports (not shown), which further proves that peak a can be attributed to the reduction of PdO.
The results of classical TPR experiments for CeO2-ZrO2 mixed oxide show two peaks at 500 and 830 °C, which have been, respectively, attributed to reduction of the surface and the bulk (24). The three peaks in the range of 150-400 °C are also associated with reduction of the surface, and are assigned to reduction of small crystallites, the surface of larger crystallites and some subsurface reduction of the larger crystallites as reported (9, 16, 23). In fact, it was shown that the TPR behavior of these mixed oxides depends on different
factors such as pretreatment conditions, degree of sintering, and phase structure (25-27). In our previous study, we have found that the bulk reduction temperature of CeO2-ZrO2 solid solution increased with the increase of Zr content, and no bulk reduction occurred for Ce0.2Zr0.8O2 in the range of 30-1000 °C. Therefore, the absence of bulk reduction for the corresponding catalyst is easy to understand.
Based on the amount of H2 consumption observed over a standard CuO sample in similar TPR procedures, the amount of mobile oxygen reacted with H2 in the fresh and aged catalysts were estimated and the data are summarized in SI Tables S1 and S2, respectively.
In comparison with the TPR profile of the support, the presence ofPdproduces the well-established overall decrease in the reduction temperature, which indicates that the noble metal particles cause spillover of hydrogen onto the support inducing a concurrent reduction of both the metal oxide and the surface of solid solution (8). Regarding SI Table S1, it was noticed that the total amount of theH2 consumption of peak a is too large to be reasonably attributed to the reduction of noble metal oxides, the theoreticalH2 consumption of which is just 40.84 μmol/gcat, indicating the back-spillover of the oxygen process from the support to the PdO surface (28, 29). Moreover, all the Pd/CZR catalysts showed increased total H2 uptake than Pd/CZ, especially for peak a, indicating that the appearance of rare earth have an effect on the reducibility of both the solid solution and the noble metal. From what has been discussed above, we may draw a conclusion that there is a strong interaction between supports and noble metal (30), and the presence of rare earth shows a promotional effect on this interaction.
大哥能不能别这么坑爹,我要的是自己翻译的,这软件翻译的牛头不对马嘴啊,求高手求高手
结果的一系列的连续TPR概要文件的淡水和催化剂岁如图1所示。
For the fresh catalysts, all of the samples exhibit a dominate low-temperature reduction feature at ca. 65 °C (peak a)andthree small peaks denoted by b, c,anddappeared in the range of 150-400 °C.
对新催化剂,所有的样品展示一个主导的低温还原特性在公元65°C(峰值)找小峰值用b,C,anddappeared数量在150 - 400年°C。
Previous investigations have
先前的调查
reported that palladium oxide is reduced to palladium on exposure to H2 at room temperature (22, 23).
报道称,钯氧化物是减少对钯在接触H2室温(22、23)。
In addition, no characterization was observed below 150 °C in the TPR profiles of fresh supports (not shown), which further proves that peak a can be attributed to the reduction of PdO.
此外,没有表征观测°C的低于150 TPR的概要的新鲜的支持(没有显示),这进一步证明了峰值可以归因于PdO的减少。
The results of classical TPR experiments for CeO2-ZrO2 mixed oxide show two peaks at 500 and 830 °C, which have been, respectively, attributed to reduction of the surface and the bulk (24).
实验的结果为CeO2-ZrO2古典TPR混合氧化物显示两个高峰期在500年和830年°C,它们已经分别归因于降低的表面和散装(24)。
The three peaks in the range of 150-400 °C are also associated with reduction of the surface, and are assigned to reduction of small crystallites, the surface of larger crystallites and some subsurface reduction of the larger crystallites as reported (9, 16, 23).
三峰的数量在150 - 400年°C减少同样有关联的表面,然后被分配到降低的小晶体,较大的晶体的表面和一些地下减少较大的晶体作为报道(9,16日,23)。
In fact, it was shown that the TPR behavior of these mixed oxides depends on different
事实上,这是表明TPR行为的混合氧化物取决于不同
factors such as pretreatment conditions, degree of sintering, and phase structure (25-27).
预处理条件等因素的严重程度、烧结、相结构(25 - 27)。
In our previous study, we have found that the bulk reduction temperature of CeO2-ZrO2 solid solution increased with the increase of Zr content, and no bulk reduction occurred for Ce0.2Zr0.8O2 in the range of 30-1000 °C.
我们在以前的研究中,我们发现,大部分的CeO2-ZrO2固体溶液还原温度增加而增加的Zr含量,也没有减少对Ce0.2Zr0.8O2大部分发生在30 - 1000的范围°C。
Therefore, the absence of bulk reduction for the corresponding catalyst is easy to understand.
因此,没有批量减相应的催化剂是容易理解的。
基于数量的H2消费观察了一个标准样品在类似程序措TPR,大量的移动氧气对H2新鲜催化剂和年迈的估算,并对数据进行了总结在SI表S1和S2,分别。
In comparison with the TPR profile of the support, the presence ofPdproduces the well-established overall decrease in the reduction temperature, which indicates that the noble metal particles cause spillover of hydrogen onto the support inducing a concurrent reduction of both the metal oxide and the surface of solid solution (8). Regarding SI Table S1, it was noticed that the total amount of theH2 consumption of peak a is too large to be reasonably attributed to the reduction of noble metal oxides, the theoreticalH2 consumption of which is just 40.84 μmol/gcat, indicating the back-spillover of the oxygen process from the support to the PdO surface (28, 29).
相比于TPR剖面的支持,ofPdproduces存在下降的公认的还原温度,这表明高贵的金属颗粒导致溢出的氢到支持制造并发减少双方的金属氧化物和固体表面的解决方案(8)。关于SI Table S1,人们注意到theH2消费总额最高的太大了,无法合理归因于降低贵金属氧化物,theoreticalH2消费的μmol / gcat仅为40.84,表明back-spillover的氧气过程从支持PdO表面(28、29)。
Moreover, all the Pd/CZR catalysts showed increased total H2 uptake than Pd/CZ, especially for peak a, indicating
此外,所有的Pd / CZR催化剂显示增加了总比Pd / CZ H2吸收,尤其是对峰值,表示that the appearance of rare earth have an effect on the reducibility of both the solid solution and the noble metal.
外观,稀土可产生影响双方的固溶和高尚的金属。
From what has been discussed above, we may draw a conclusion that there is a strong interaction between supports and noble metal (30), and the presence of rare earth shows a promotional effect on this interaction.
通过以上讨论,我们可以得出一个结论,有强有力的支持和贵金属之间的交互(30),现有的稀土显示了在这个互动宣传效果。
望采纳!!!
图1示出了新制和老化的催化剂的一系列连续TPR截图。所有新制催化剂样品呈现出低温为主的还原特性,65°C附近出现峰a,还有三个小峰以b,c表示【注】,而在150-400°C范围内还原性消失。先前的研究报道认为在室温下,氧化钯置于H2中可被还原为金属钯(22、23)。而新制的(催化剂)载体在TPR截图上低于150°C区域未观察到特征峰(该图未在这里给出),这进一步证明峰a可以归属于PdO被还原。
【注】原文此处恐有误,或原文表述不够恰当。
The results of classical TPR experiments for CeO2-ZrO2 mixed oxide show two peaks at 500 and 830 °C, which have been, respectively, attributed to reduction of the surface and the bulk (24). The three peaks in the range of 150-400 °C are also associated with reduction of the surface, and are assigned to reduction of small crystallites, the surface of larger crystallites and some subsurface reduction of the larger crystallites as reported (9, 16, 23). In fact, it was shown that the TPR behavior of these mixed oxides depends on different factors such as pretreatment conditions, degree of sintering, and phase structure (25-27). In our previous study, we have found that the bulk reduction temperature of CeO2-ZrO2 solid solution increased with the increase of Zr content, and no bulk reduction occurred for Ce0.2Zr0.8O2 in the range of 30-1000 °C. Therefore, the absence of bulk reduction for the corresponding catalyst is easy to understand.
CeO2-ZrO2混合氧化物的经典TPR实验结果中出现了两个峰500和830°C,它们分别归属为(混合物)表面和本体的还原(24)。在150 - 400°C之间的三个峰同样与表面的还原有关,它们可归属为小晶粒,较大晶粒(上)表面和下表面的还原,正如文献(9,16,23)报道的那样。事实上,人们业已证明这些混合氧化物的TPR行为依赖于诸如预处理条件、烧结程度、相结构等不同因素(25 - 27)。我们先前的研究发现CeO2-ZrO2固溶体的本体还原温度随Zr含量增大而升高,并且Ce0.2Zr0.8O2在30 - 1000°C的范围内不发生本体还原。因此,对应催化剂不存在本体还原是容易理解的。
Based on the amount of H2 consumption observed over a standard CuO sample in similar TPR procedures, the amount of mobile oxygen reacted with H2 in the fresh and aged catalysts were estimated and the data are summarized in SI Tables S1 and S2, respectively.
根据标准CuO样品进行的类似TPR实验中测出的H2消耗量,可以估算出新制和老化的催化剂中与H2反应的流动氧气量,H2和O2消耗量数据分别汇总在补充材料(SI)的S1和S2表中。
In comparison with the TPR profile of the support, the presence of Pd produces the well-established overall decrease in the reduction temperature, which indicates that the noble metal particles cause spillover of hydrogen onto the support inducing a concurrent reduction of both the metal oxide and the surface of solid solution (8).
对比载体的TPR截图,Pd的存在引起还原温度总体上降低(这业已被公认),这表明贵金属(Pd)粒子引起氢气流向载体表面,诱导金属氧化物和固溶体表面同时发生还原(8)。
Regarding SI Table S1, it was noticed that the total amount of the H2 consumption of peak a is too large to be reasonably attributed to the reduction of noble metal oxides, the theoreticalH2 consumption of which is just 40.84 μmol/gcat, indicating the back-spillover of the oxygen process from the support to the PdO surface (28, 29).
从补充材料的S1表中可见,峰a消耗的H2量太大(理论耗氢量仅为40.84 μmol/gcat),以至于不能归属为贵金属氧化物的还原【注】,这意味着存在自载体流向PdO表面的逆向氧气流。
【注】文章不完整,各部分的逻辑关系不很清楚(作者的表达逻辑个人感觉也有点问题),此处看起来与首段自相矛盾,第一段和后面各段讲的应当不是同一回事。
Moreover, all the Pd/CZR catalysts showed increased total H2 uptake than Pd/CZ, especially for peak a, indicating that the appearance of rare earth have an effect on the reducibility of both the solid solution and the noble metal. From what has been discussed above, we may draw a conclusion that there is a strong interaction between supports and noble metal (30), and the presence of rare earth shows a promotional effect on this interaction.
此外,所有Pd/CZR催化剂显示出比Pd/CZ催化剂更高的H2总吸收量,尤其是峰a,表明稀土的存在对固溶体和贵金属氧化物的还原产生影响。由上文讨论可以得出结论,即载体和贵金属间存在强的相互作用 (30),而稀土的存在对相互作用具有促进效应。