光催化CO₂还原过程通过模拟光合作用，利用太阳能将CO₂和H₂O转化成燃料和高价值化学品的反应过程，光催化方法以其绿色、条件温和等特点被认为是解决全球能源和环境问题最有前途的方案之一[1, 2]。

由于光催化CO₂还原反应涉及的产物种类较多，反应产生不同的不同产物是因反应过程中所需电子数不同引起的，因此光催化CO₂还原反应中不同产率的计算方法与反应过程中转移的电子数息息相关。现整理出光催化CO₂还原反应中明确不同具体产物及其对应转移电子数表格，见下表：

表1.CO₂还原为各种产物及相应电极反应式[3].

光催化CO₂还原反应涉及的活性评级指标主要包括以下6种：

1.目标产物反应速率（R产物）[4]：单位时间内，单位质量催化剂产生的目标产物的物质的量，计算公式如下：

2.电子消耗速率（R电子）[5]：参与反应的有效光生电子速率，计算公式如下：

3.理论产氧量[6]：根据参与反应的有效光生电子数（空穴数）推导出反应所能生成的O₂含量。

4.选择性（S产物）[7]：目标产物的量占产物总量的百分比。

5.表观量子产率（Apparent Quantum Yield，AQY）[4]：反应体系在特定单色波长下，反应转移的电子数与入射光子数之比。

6.太阳能-化学能转化效率（Solar to Chemical Energy Conversion Efficiency，STC）[8]：输入太阳能转化为化学能的效率，计算公式如下：

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参考文献

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