00496nas a2200121 4500008004100000245007800041210006900119260003000188490000900218100002200227700002000249856010500269 2020 eng d00aAdvanced heterogeneous catalysts volume 1: applications at the nano-scale0 aAdvanced heterogeneous catalysts volume 1 applications at the na bAmerican Chemical Society0 v13591 aSudarsanam, Putla1 aSingh, Lakhveer uhttps://library.ncl.res.in/content/advanced-heterogeneous-catalysts-volume-1-applications-nano-scale00510nas a2200121 4500008004100000245008500041210006900126260003000195490000900225100002200234700002000256856011200276 2020 eng d00aAdvanced heterogeneous catalysts volume 2: applications at the single-atom scale0 aAdvanced heterogeneous catalysts volume 2 applications at the si bAmerican Chemical Society0 v13601 aSudarsanam, Putla1 aSingh, Lakhveer uhttps://library.ncl.res.in/content/advanced-heterogeneous-catalysts-volume-2-applications-single-atom-scale03339nas a2200205 4500008004100000245006000041210005900101260000900160300001100169490000900180520269400189100001802883700002702901700002702928700003002955700002102985700001703006700002203023856008803045 2020 eng d00aAdvances in single-atom catalysts for lignin conversion0 aAdvances in singleatom catalysts for lignin conversion bACS  a93-1250 v13603 a

Single-atom catalysts (SACs) have drawn significant attention as promising surfaces for promoting observable reaction processes. As a guideline, SACs should have the proper nanoscale dimensionality to influence their effective and efficient performance, especially during lignin conversion to platform chemicals and other useful products. The development of SACs for functional applications still has many difficulties, such as harnessing and improving low-coordinated metal atoms to have controlled and observable activities per metal atom. Consequently, the need arises to ensure a decrease in the size of the metal particles and their uniform dispersion or coordination on a suitable support material. This has been an industrial target for a long time in the field of catalysis. Supported metal-based catalysts are not dimensionally uniform, thereby reducing their metal-atom efficiency and frequently leading to undesired side reactions that are sometimes difficult to observe. This makes the identification of the active sites responsible for the reaction of interest very difficult or even impossible. To ameliorate this challenge, the ultimate small-size limit for a metal particle is the SAC, which contains isolated metal atoms singly dispersed on any suitable support materials. It is expected that SACs should maximize the metal-atom efficiency with respect to the application, which is particularly significant for supported metal catalysts. Moreover, through uniform single-atom dispersion, SACs offer a great opportunity for achieving high activity and tuning selectivity to the desired product. This chapter provides a comprehensive overview of recent advances in using SACs for the conversion of lignin or lignin model compounds. The different support materials used for SACs, such as zeolites, metal oxides, and carbonaceous and siliceous materials, are discussed. This contribution also covers the catalytic reactions of lignin with an emphasis on cleaving its specific linkages, along with a systematic evaluation of SACs used in the relevant processes. The chapter also addressed key parameters essential for tailoring the particle size and acid–base and redox properties of the SACs used in lignin conversion. Special attention is paid to understanding the role of synthesis conditions in tailoring the size of SACs. It is expected that this contribution will provide future directions for practical SAC development and implementation in lignin conversion.

1 aHalilu, Ahmed1 aUmar, Ahmad, Abulfathi1 aBalarabe, Yahaya, Umar1 aHaniffa, Mhd., Abd. Cader1 aMunawar, Khadija1 aSunku, Kiran1 aSudarsanam, Putla uhttps://library.ncl.res.in/content/advances-single-atom-catalysts-lignin-conversion02345nas a2200253 4500008004100000022001400041245011300055210006900168260000900237300001600246490000700262520142600269653003101695653004101726653003601767653002201803653003201825100001801857700001901875700002501894700001901919700002201938856013101960 2025 eng d a2168-048500aAdditive-free, selective synthesis of N-heteroaromatics using morphology-engineered hollow CeO2 nanocatalyst0 aAdditivefree selective synthesis of Nheteroaromatics using morph cDEC  a21266-212760 v133 a

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.

10aacid-base and defect sites10aadditive-free aerobicdehydrogenation10aCeO2 hollow nanosphere catalyst10aN-heteroaromatics10areusability and scalability1 aSingh, Nittan1 aSwapna, Bhattu1 aBalu, Alina, Mariana1 aBhatte, Kushal1 aSudarsanam, Putla uhttps://library.ncl.res.in/content/additive-free-selective-synthesis-n-heteroaromatics-using-morphology-engineered-hollow-ceo2