Wang Shuling, He Fengting, Lu Yangming, Wu Yuzhao, Zhang Yang, Dong Pei, Liu Xiaoming, Zhao Chaocheng, Wang Shuaijun, Wang Dejun, Zhang Jinqiang, Wang Shaobin
State Key Laboratory of Petroleum Pollution Control, China University of Petroleum (East China), 66 West Changjiang Road, Qingdao 266580, PR China.
State Key Laboratory of Petroleum Pollution Control, China University of Petroleum (East China), 66 West Changjiang Road, Qingdao 266580, PR China.
J Colloid Interface Sci. 2024 Jan 15;654(Pt A):317-326. doi: 10.1016/j.jcis.2023.10.046. Epub 2023 Oct 12.
Mass transfer enhancement and crystallinity engineering are two prevailing technologies for photocatalyst modification. However, their relative effectiveness in enhancing photocatalytic activity remains unclear due to the lack of rational probing catalysts. In this study, we synthesized two distinct carbon nitride (CN) catalysts: one with a high specific surface area (CN-HA) and the other with improved crystallinity (CN-HC). These catalysts served as probes to compare their respective impacts on photocatalytic activities. Comprehensive characterization techniques and density functional theory (DFT) calculation results unveiled that crystallinity played a dominant role in light absorption and charge dynamics, while surface area primarily influenced mass transfer in photocatalysis. Importantly, our findings revealed that crystallinity engineering of photocatalyst achieved a greater impact on photocatalytic hydrogen evolution than that from mass transfer enhancement. Consequently, CN-HC demonstrated a remarkable improvement in photocatalytic performance for hydrogen evolution (6465.4 μmol h g), surpassing both CN and CN-HA by 19.4- and 2.4-fold, respectively, accompanied by a high apparent quantum yield of 23.8 % at 420 nm. This study not only unveils the dominant factor influencing the activity of photocatalysts but also provides a modified approach for robust solar fuel production, shedding light on the path toward efficient and sustainable energy conversion.
传质增强和结晶度工程是两种流行的光催化剂改性技术。然而，由于缺乏合理的探针催化剂，它们在提高光催化活性方面的相对有效性仍不明确。在本研究中，我们合成了两种不同的氮化碳（CN）催化剂：一种具有高比表面积（CN-HA），另一种具有改善的结晶度（CN-HC）。这些催化剂用作探针，以比较它们对光催化活性的各自影响。综合表征技术和密度泛函理论（DFT）计算结果表明，结晶度在光吸收和电荷动力学中起主导作用，而表面积主要影响光催化中的传质。重要的是，我们的研究结果表明，光催化剂的结晶度工程对光催化析氢的影响比传质增强更大。因此，CN-HC在析氢的光催化性能方面表现出显著改善（6465.4 μmol h g），分别比CN和CN-HA高出19.4倍和2.4倍，在420 nm处具有23.8%的高表观量子产率。本研究不仅揭示了影响光催化剂活性的主导因素，还为强大的太阳能燃料生产提供了一种改性方法，为高效和可持续能源转换的道路指明了方向。
