Photocatalytic nicotinamide adenine dinucleotide (NADH) regeneration coupled with enzymatic CO₂ reduction holds significance for global sustainable development. In this work, acrylonitrile-linked covalent organic frameworks (COFs) loaded on NH₂–Ti₃C₂T_x (MXene) forms a lawn-like TP-COFs/Ti₃C₂T_x (TCM) photocatalyst for NADH regeneration. The optimum photocatalyst TCM-15% achieves a 95% NADH regeneration yield within 30 min. More importantly, the TCM-15% obtains 46% NADH regeneration yield without an electron mediator ([Cp*Rh(bpy)(H₂O)]²⁺), even higher than that of the pure TP-COFs with an electron mediator (42%). In the presence and absence of an electron mediator, the NADH regeneration TOF values of TCM-15% were 3.69 and 1.42 h^–1, respectively, which were 4.05 and 4.90 times higher than those of pure TP-COFs. Subsequently, in the photoenzymatic catalytic cascade system, the formate formation rates reached 2380 and 543 μmol g^–1 h^–1, with and without an electron mediator, respectively. This work has laid a great foundation for achieving efficient NADH regeneration and cascade enzyme catalysis without an electron mediator.

中文翻译：

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草坪状 TP-COF/Ti3C2TX (MXene) 光催化剂实现酶促 CO2 还原，无需电子介体即可高效再生 NADH

光催化烟酰胺腺嘌呤二核苷酸（NADH）再生与酶促CO ₂还原对全球可持续发展具有重要意义。在这项工作中，负载在NH ₂ –Ti ₃ C ₂ T _x (MXene)上的丙烯腈连接的共价有机框架(COF)形成了草坪状的TP-COFs/Ti ₃ C ₂ T _x (TCM)光催化剂，用于NADH再生。最佳光催化剂TCM-15%可在30分钟内实现95%的NADH再生率。更重要的是，TCM-15%在没有电子介体的情况下获得了46%的NADH再生率（[Cp*Rh(bpy)(H ₂ O)] ²⁺），甚至高于有电子介体的纯TP-COFs (42%)。在电子介体存在和不存在的情况下，TCM-15%的NADH再生TOF值分别​​为3.69和1.42 h ^–1，分别是纯TP-COFs的4.05和4.90倍。随后，在光酶催化级联系统中，有或没有电子介体时，甲酸形成率分别达到 2380 和 543 μmol g ^–1 h ^–1 。该工作为实现无电子介体的NADH高效再生和级联酶催化奠定了良好的基础。