The efficient utilization of lignin remains a great challenge due to its complex nonrepetitive structure and the lack of efficient catalyst. Herein, a single-atom catalyst Ni@N-C was designed via a facile chelation-anchored strategy. Ni atoms were immobilized on the N-doped carbon carrier by a two-stage pyrolysis of a mixture of d-glucosamine hydrochloride, nickel acetate, and melamine. d-glucosamine hydrochloride as a chelating agent prevented the aggregation of Ni²⁺, and melamine provided enough N to anchor Ni by forming Ni–N₄ structure. Ni@N-C gave a 31.2% yield of aromatic compounds from lignin hydrogenolysis, which was twice higher than that achieved by Ni cluster catalyst. Based on the experimental and density functional theory (DFT) calculation results, the higher activity of Ni@N-C was attributed to its lower H₂ dissociation energy and the reduced energy barriers of the transition states. The strategy described opens an efficient green avenue for preparing single-atom catalyst that possesses outstanding activity in lignin depolymerization.

中文翻译：

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通过螯合锚定策略在 N 掺杂碳上构建单原子 Ni 用于木质素氢解

由于木质素复杂的非重复结构和高效催化剂的缺乏，其高效利用仍然是一个巨大的挑战。在此，通过简单的螯合锚定策略设计了单原子催化剂 Ni@NC。通过d-氨基葡萄糖盐酸盐、乙酸镍和三聚氰胺的混合物的两阶段热解，将 Ni 原子固定在 N 掺杂的碳载体上。d-氨基葡萄糖盐酸盐作为螯合剂阻止了 Ni ²⁺的聚集，三聚氰胺通过形成 Ni–N _{4提供了足够的 N 来锚定 Ni}结构体。Ni@NC 从木质素氢解中得到 31.2% 的芳香族化合物产率，比 Ni 簇催化剂高出两倍。基于实验和密度泛函理论 (DFT) 计算结果，Ni@NC 较高的活性归因于其较低的 H ₂解离能和过渡态能垒的降低。所描述的策略为制备在木质素解聚中具有出色活性的单原子催化剂开辟了一条有效的绿色途径。