清华大学王定胜团队报道了单原子和路易斯酸位点协同作用将木质素高效和选择性地分解成单酚类衍生物。相关研究成果发表在2023年5月30日出版的《美国化学会杂志》。

木质素是天然可再生木质纤维素生物质资源中含量最丰富的芳香族聚合物。开发用于木质素解聚的高效催化剂，以高产率和高选择性生产有价值的单酚，在该领域仍然是一个理想但具有挑战性的目标。

该文中，研究人员设计了一种协同催化剂，将原子分散的Mo中心和MgO基底上的Al-Lewis酸位点结合在一起（Mo₁Al/MgO），用于通过β-芳基醚键断裂解聚桉树木质素。Mo₁Al/MgO在惰性N₂气氛中同时实现了46%的接近理论的单酚产率，对针叶树基和芥子基甲醚的超高选择性为92%，以及良好的循环耐久性。第一性原理计算和对照催化实验证实了在甲醇溶剂的参与下，Mo₁–O₅单原子中心与相邻的Al-Lewis酸位点之间的协同催化机制。

该研究验证了设计具有协同多活性位点的性能更好的催化剂的可行性，用于将复杂的可再生生物聚合物高效和选择性地分解成具有更低成本和更高安全性的高附加值产品。

附：英文原文

Title: Synergy of Single Atoms and Lewis Acid Sites for Efficient and Selective Lignin Disassembly into Monolignol Derivatives

Author: Ge Meng, Wu Lan, Lilong Zhang, Shibin Wang, Tanhao Zhang, Shuo Zhang, Ming Xu, Yu Wang, Jian Zhang, Fengxia Yue, Yulong Wu, Dingsheng Wang

Issue&Volume: May 30, 2023

Abstract: Lignin is the most abundant aromatic polymer from the natural and renewable lignocellulosic biomass resource. Developing highly efficient catalysts for lignin depolymerization to produce valuable monophenols with high yield and selectivity remains a desirable but challenging target in this field. Here, we design a synergistic catalyst combining atomically dispersed Mo centers and Al Lewis acid sites on a MgO substrate (Mo1Al/MgO) for the depolymerization of Eucalyptus lignin via the β-aryl ether bond cleavage. A near-theoretical monophenol yield of 46% with an ultrahigh selectivity of 92% for coniferyl and sinapyl methyl ether, as well as good cycling durability, was achieved simultaneously by Mo1Al/MgO in an inert N2 atmosphere. First-principles calculations and control catalytic experiments confirmed the synergistic catalysis mechanism between Mo1–O5 single-atom centers and the neighboring Al Lewis acid sites with the participation of a methanol solvent. This study validates the feasibility of designing better-performing catalysts with synergistic multiactive sites for the efficient and selective disassembly of complex renewable biopolymers into highly value-added products with lower cost and greater security.

DOI: 10.1021/jacs.3c04028

Source: https://pubs.acs.org/doi/10.1021/jacs.3c04028