“碳达峰、碳中和”是我国统筹国内外局势做出的重大战略决策，是着力解决资源环境约束突出问题、构建人类命运共同体的庄严承诺。碳捕集与封存技术（CCS）作为传统的CO2治理方法存在潜在的泄漏风险且会造成巨大的经济负担。近年来，碳捕集、利用与封存技术(CCUS)由于可将捕集的CO2转化为附加值产品以实现资源化利用，被认为是CCS的有效替代和补充方案。发展高效的CO2资源化技术是CCUS的关键。酶催化技术作为典型的绿色生物制造技术在CO2资源化利用领域受到广泛关注。构建以酶催化为基础的耦合催化系统为CO2到高值化学品或燃料的资源化转化创造了丰富的路径网络。综述了近年来基于生物酶介导的“酶+X”耦合催化CO2资源化转化系统，包括“酶+酶”耦合催化系统、“酶+化学”耦合催化系统、“酶+光”耦合催化系统和“酶+电”耦合催化系统。对不同耦合催化系统的结构进行解析，明确了系统特点及催化反应过程。在结构解析的基础上讨论了系统模块设计与性能强化的关键。阐述了“酶+X”耦合催化系统应用于CO2资源化转化的优势与不足，并对其未来发展方向提供了建议。“酶+酶”耦合催化系统较单酶催化系统丰富了CO2转化为目标产物的路径可设计性，可通过多步反应促使CO2还原产物向具有更高附加值的方向转化，极大提升CO2资源化转化的经济效益。“酶+化学”耦合催化系统利用化学催化过程对CO2进行预先转化，后续的酶催化过程可直接以C1化合物作为反应底物，在催化CO2转化为C2/C2+等多碳化合物方面表现出独特优势。“酶+光”耦合催化系统模拟自然光合作用利用光能实现辅酶循环再生，避免了辅酶依赖型酶催化反应对外源性还原当量的消耗。“酶+电”耦合催化系统可通过施加外部偏压直接或间接实现电极与酶活性中心之间的有效电子迁移，继而驱动酶催化CO2加氢转化为载能化合物。“酶+X”耦合催化系统弥补了单一的酶催化系统催化CO2资源化转化驱动力不足的弊端，具有独特的优势和广阔的应用前景。但不同催化系统的耦合增加了体系复杂性，需对耦合系统进行精密构筑，且酶催化剂的蛋白属性也在一定程度上影响了“酶+X”耦合系统催化CO2资源化转化的应用场景。今后一段时间，CO2捕集与封存仍是实现双碳目标的主要策略，但包括“酶+X”耦合催化CO2资源化转化技术在内的CO2利用技术将逐渐成为趋势，有望真正实现碳中和目标。

"Carbon peaking and carbon neutrality" is a major strategic decision made by our country to coordinate domestic and international situations. It is a solemn commitment to address prominent resource and environmental constraints and to build a community of human destiny. Carbon capture and storage (CCS), as a traditional carbon dioxide (CO2) control method, has potential leakage risk and a huge economic burden. In recent years, carbon capture, utilization and storage (CCUS) has been regarded as an effective alternative and supplement to CCS because it can convert the captured CO2 into value-added products for resource utilization. The development of efficient CO2 utilization technologies is the key to CCUS. Enzyme-catalyzed technology, as a typical green biomanufacturing technology, has received extensive attention in the field of CO2 utilization. The coupled catalytic systems based on enzyme catalysis open a rich pathway network for the resourceful conversion of CO2 into high-value chemicals or fuels. In this review, the "Enzyme +X" coupled catalytic systems for CO2 conversion in recent years was summarized and highlighted, including "Enzyme + Enzyme" coupled catalytic system, "Enzyme + Chemo" coupled catalytic system, "Enzyme + Photo" coupled catalytic system and "Enzyme + Electro" coupled catalytic system. The structures of different coupled catalytic systems were analyzed, and their system characteristics and catalytic processes were clarified. On the basis of structural analysis, the key to system module design and performance enhancement was discussed. The advantages and disadvantages of the "Enzyme + X" coupled catalytic system in CO2 resource conversion were expounded, and suggestions for its future development were provided. In an "Enzyme + Enzyme" coupled catalytic system, the pathway designability of CO2 conversion to target products is enriched, which can ensure the final products with higher value through the cascade reactions, thus greatly improving the economic efficiency. In an "Enzyme + Chemo" coupled catalytic system, the chemical catalytic process is usually applied to pre-convert CO2, after which the enzyme catalytic process directly uses C1 compounds as the starting materials, showing unique advantages in catalyzing the conversion of CO2 into C2/C2+ and other multi-carbon compounds. In an "Enzyme + Photo" coupled catalytic system, light energy is utilized by semiconducting materials to trigger the catalytic regeneration of coenzyme, avoiding the consumption of exogenous reduction equivalents in coenzyme-dependent enzymatic catalytic reactions. In an "Enzyme + Electro" coupled catalytic system, the electron transfer between the electrode and the enzyme can be regulated by altering the external bias voltage, which is rather crucial for driving the enzymatic hydrogenation in a high efficiency manner. The "Enzyme +X" coupled catalytic system can compensate for the drawbacks of the sole or single enzyme catalytic system to convert CO2 into energy-carrying compounds, which shows unique advantages and broad application prospects. However, the coupling of different catalytic systems increases the complexity of the system and requires precise construction of the coupled system. Meanwhile, the enzyme as a typical protein molecule may also affect the application of the "Enzyme +X" coupled system in some extreme external conditions. Although CO2 capture and storage is still the major strategy to achieve the goal of "carbon peaking and carbon neutrality" in near future, CO2 utilization technologies, including "Enzyme +X" coupled catalytic CO2 conversion technology, will gradually become a trend, which is expected to truly achieve the carbon neutralization goal the future.

0 引言

1 酶+X”耦合催化CO2资源化转化

   1.1 “酶+酶”耦合催化CO2资源化转化

   1.2 “酶+化学”耦合催化CO2资源化转化

   1.3 “酶+光”耦合催化CO2资源化转化

   1.4 “酶+电”耦合催化CO2资源化转化

2 结语与展望