@article {49931,
	title = {Additive-free, selective synthesis of N-heteroaromatics using morphology-engineered hollow CeO2 nanocatalyst},
	journal = {ACS Sustainable Chemistry \& Engineering},
	volume = {13},
	year = {2025},
	month = {DEC },
	pages = {21266-21276},
	type = {Article},
	abstract = {<p>
	We developed a highly efficient, shape-controlled CeO2 nanocatalyst for synthesizing N-heteroaromatics via an aerobic dehydrogenation approach, operating at mild reaction conditions without needing toxic acid/base additives. Different morphologies of CeO2, namely, hollow nanospheres, nanorods, and irregularly shaped nanoparticles, were synthesized, as confirmed by electron microscopy analysis. The CeO2 hollow nanosphere catalyst (CeO2-HNS) exhibited unique features, such as abundant acid-base sites, larger-sized voids, and surface oxygen vacancies. These characteristics are found to be crucial for the additive-free oxidative dehydrogenation of saturated N-heterocycles over the CeO2-HNS catalyst, resulting in 98\% conversion of 1,2,3,4-tetrahydroquinoline with 100\% quinoline product selectivity. The versatility of this approach was further demonstrated by the successful aerobic dehydrogenation of a broad range of saturated N-heterocycles, affording N-heteroaromatics in good to excellent yields. Furthermore, the CeO2-HNS nanocatalyst showed exceptional reusability over six cycles without requiring a regeneration step, such as high-temperature calcination treatment. The structural and morphological stability of the CeO2-HNS catalyst, along with reaction scalability and favorable green chemistry metrics, emphasized the practical viability of the CeO2-HNS catalyst for industrial applications.</p>
},
	keywords = {acid-base and defect sites, additive-free aerobicdehydrogenation, CeO2 hollow nanosphere catalyst, N-heteroaromatics, reusability and scalability},
	issn = {2168-0485},
	doi = {10.1021/acssuschemeng.5c10285},
	author = {Singh, Nittan and Swapna, Bhattu and Balu, Alina Mariana and Bhatte, Kushal and Sudarsanam, Putla}
}
