<br>通过在 Co3O4 上用单层 Cs 原子制造 Cs-O-Co 结构来促进 N2O 分解,Environmental Science & Technology

当前位置： X-MOL 学术 › Environ. Sci. Technol. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

通过在 Co3O4 上用单层 Cs 原子制造 Cs-O-Co 结构来促进 N2O 分解
Environmental Science & Technology ( IF 10.8 ) Pub Date : 2023-12-21 , DOI: 10.1021/acs.est.3c06940
Yuanyu Gong ₁ , Zhisong Liu ₁ , Zihao Li ₁ , Caixia Liu ₂ , Naiqiang Yan ₁ , Lei Ma ₁

Affiliation

开发有效的低温 N ₂ O 分解催化剂具有挑战性。其中，Cs-O-Co结构作为Cs单层原子在纯Co ₃ O ₄上制备的活性物种，最初在模拟汽车尾气和硝酸厂烟气中表现出良好的N ₂ O分解催化活性。对于Na、K和Rb碱金属在Co ₃ O ₄催化剂上对于N ₂ O分解也观察到类似的催化性能，这说明在实际应用中碱金属促进相对于Co ₃ O ₄的普遍性。催化结果表明，负载4 wt% Cs的Co ₃ O ₄催化剂在300 ℃下的TOF比纯Co ₃ O ₄催化剂高近2个数量级。有趣的是，在掺杂相同Cs负载量的Co ₃ O ₄催化剂上，N ₂ O分解的转化率受到显着抑制。表征结果表明，初级活性Cs–O–Co结构是由Cs 6s和O 2p轨道在负载型Co ₃ O ₄催化剂上的高轨道杂化形成的，其中Cs可以向Co ³⁺提供电子并产生更多的电子。钴²⁺ 。相比之下，掺杂的Co ₃ O ₄催化剂主要由Cs ₂ O ₂物质组成；同时，吸附水蒸气产生CsOH物质，导致催化活性显着下降。原位漂移、严格动力学和DFT结果详细阐述了N ₂ O分解的反应机理，其中吸附的N ₂ O的直接分解是在不存在O ₂的情况下负载型催化剂上的动力学相关步骤。同时，观察到活性氧对吸附的N ₂ O 分解的帮助是O ₂存在下的动力学相关步骤。这些结果可能为开发用于高效 N ₂ O 分解的碱金属促进催化剂铺平了一条有希望的道路。

"点击查看英文标题和摘要"

Boosting N2O Decomposition by Fabricating the Cs–O–Co Structure over Co3O4 with Single-Layer Atoms of Cs

Developing effective catalysts for N₂O decomposition at low temperatures is challenging. Herein, the Cs–O–Co structure, as the active species fabricated by single-layer atoms of Cs over pure Co₃O₄, originally exhibited great catalytic activity of N₂O decomposition in simulated vehicle exhaust and flue gas from nitric acid plants. A similar catalytic performance was also observed for Na, K, and Rb alkali metals over Co₃O₄ catalysts for N₂O decomposition, illustrating the prevalence of alkali-metal-promotion over Co₃O₄ in practical applications. The catalytic results indicated that the TOF of Co₃O₄ catalysts loaded by 4 wt% Cs was nearly 2 orders of magnitude higher than that of pure Co₃O₄ catalysts at 300 °C. Interestingly, the conversions of N₂O decomposition over Co₃O₄ catalysts doped by the same Cs loadings were significantly inhibited. Characterization results indicated that the primary active Cs–O–Co structure was formed by highly orbital hybridization between the Cs 6s and the O 2p orbital over the supported Co₃O₄ catalysts, where Cs could donate electrons to Co³⁺ and produce much more Co²⁺. In contrast, the doped Co₃O₄ catalysts were dominated by Cs₂O₂ species; meanwhile, CsOH species was generated by adsorbed water vapor led to a significant decrease in catalytic activity. In situ DRIFTS, rigorous kinetics, and DFT results elaborated the reaction mechanism of N₂O decomposition, where the direct decomposition of adsorbed N₂O was the kinetically relevant step over supported catalysts in the absence of O₂. Meanwhile, the assistance of adsorbed N₂O decomposition by activated oxygen was observed as the kinetically relevant step in the presence of O₂. The results may pave a promising path toward developing alkali-metal-promotion catalysts for efficient N₂O decomposition.

更新日期：2023-12-21

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南