Ti Substitution-Induced Inter-Site Distance Effect (ISDE) in Hierarchical Porous Cobalt Titanium Oxide Promoting Selective NH3 Oxidation for Enhanced Energy Release

影响因子：8.2

DOI码：10.1021/acsami.6c01574

发表刊物：ACS Applied Materials & Interfaces

关键字：Cobalt titanium oxide, Ammonium perchlorate, Selective NH3 oxidation, Synergistic catalysis, Intersite distance effect

摘要：The combustion efficiency and energy release capacity of solid rocket propellants (SRPs) are predominantly determined by the thermal decomposition behavior of ammonium perchlorate (AP), the core oxidizer. Developing high-efficiency catalysts and deciphering their intrinsic catalytic mechanisms remain a critical challenge. In this work, Ti4+ substitution modulates the distance between Co–Co active sites, triggering a unique intersite distance effect (ISDE) in hierarchical porous Co2TiO4 nanoflower catalysts. Their catalytic performance and intrinsic mechanism for AP thermal decomposition were systematically investigated. The shorter Co–Co active site distance enhances the electronic synergistic effect by enabling a stable “bridged adsorption” dual-site mechanism, potentially breaking the scaling relations between intermediate adsorption energies, and thus significantly improving catalytic performance. This ISDE synergizes with the hierarchical porous structure, optimizing the electronic structure of Co sites (the d-band center shifts 0.3 eV toward the Fermi level), enhancing the adsorption and activation capacity of reaction intermediates, and regulating the NH3 oxidation pathway, increasing the selectivity of NO2 to 48.4%, accompanied by an accelerated decomposition rate and more concentrated exothermic behavior. Density functional theory (DFT) calculations further verify that Ti substitution adjusts the surface electrostatic potential and adsorption energy of reactants, facilitating the cleavage of N–H and Cl–O bonds in NH3 and HClO4, respectively. This work clarifies the critical role of ISDE in mediating catalytic activity and provides a new theoretical paradigm for the rational design of high-performance bimetallic oxide catalysts for energetic material applications, particularly in SRPs.

合写作者：Zeng Qihui,Zheng Zeyu,Tang Xiaolin,Zhou Peng

论文类型：文章

通讯作者：Zhang Yifu*,Li Shuang*,Huang Chi*

学科门类：理学

文献类型：J

卷号：XX

期号：XX

页面范围：XX-XX, 2026

是否译文：否

收录刊物：SCI

发布期刊链接：https://doi-org-s.vpn.whu.edu.cn/10.1021/acsami.6c01574

附件：

 1.ti-substitution-induced-inter-site-distance-effect-(isde)-in-hierarchical-porous-cobalt-titanium-oxide-promoting.pdf