Release of Oxygen from Copper Oxide Cluster Ions by Heat and by Reaction with NO
Release of Oxygen from Copper Oxide Cluster Ions by Heat and by Reaction with NO
复制标题
通过加热和与 NO 反应从氧化铜簇离子中释放氧气
DOI：
10.1021/jp511840d
复制
发表时间：
2015
期刊：
影响因子：
--
通讯作者：
and Keisuke Morita
中科院分区：
文献类型：
--
作者：
Fumitaka Mafune;Ken Miyajima;and Keisuke Morita
在氧气存在的情况下，通过激光烧蚀铜棒在气相中制备了氧化铜团簇CunOm+。将团簇离子从团簇源的下游加热至1000 K（后加热），并使用质谱法检查CunOm+（n= 4-19）的丰度。程序升温脱附实验表明，在T = 500 K以下，富氧的CunOm+δ+（m≈n/2 + 1; δ = 1-4）中释放出氧分子，形成近化学计量的CunOm+δ+（δ = 0-1）。氧分子进一步从团簇离子中释放出来，在800 K以上形成CunOm+δ+（δ = −1，0），这表明Cu原子在高温下可以采取+1电荷状态。在它们的热稳定性方面，我们观察到CunOm+与NO分子的反应性。结果表明，NO容易吸附在CunOm+团簇离子上，生成CunOmNO+，其准一级反应速率常数为10- 10 cm ~ 3s ~（-1）.将CunOmNO+后加热至523 K表明，富氧的CunOm+（Cu 6 O 5+、Cu 8 O 6+、Cu 9 O 7+和Cu 11 O 8+）与NO反应生成CunOm-1+和NO2，如CunOm++ NO → CunOm-1++ NO2所表示。
Copper oxide clusters, CunOm+, were prepared in the gas phase by laser ablation of a copper rod in the presence of oxygen. The cluster ions were heated up to 1000 K downstream from the cluster source (post heating), and the abundance of CunOm+(n= 4–19) was examined using mass spectrometry. Temperature-programmed desorption experiments revealed that an oxygen molecule is released from oxygen-rich CunOm+δ+(m≈n/2 + 1; δ = 1–4), forming near-stoichiometric CunOm+δ+(δ = 0–1) belowT= 500 K. Oxygen molecules are further released from cluster ions to form CunOm+δ+(δ = −1, 0) above 800 K, suggesting that a Cu atom can take a +1 charge state at high temperatures. In relation to their thermal stability, we observed the reactivity of CunOm+with NO molecules. It was found that NO readily attaches to CunOm+cluster ions, forming CunOmNO+with pseudo-first-order rate constants of ∼10–10cm3s–1. The post heating of CunOmNO+to 523 K revealed that oxygen-rich CunOm+(Cu6O5+, Cu8O6+, Cu9O7+, and Cu11O8+) reacts with NO to form CunOm-1+and NO2, as expressed by CunOm++ NO → CunOm-1++ NO2.