第一作者：Wenjuan Zhang,
通讯作者：吉林大学 刘钢
DOI：https://doi.org/10.1021/acscatal.4c02285
有机光催化剂为将太阳能转化为可储存的化学产品提供了令人振奋的机会。它们错综复杂的空间结构，精确定制，提供了对光吸收特性和载流子有效传输的控制水平。尽管如此，催化性能的最新进展主要源于对已有共轭基质结构的战略性破坏和随后的重新配置。在这项工作中，作者基于最近报道的瞬态自双极化框架开发了一种分子助催化剂策略，以提高光催化性能。结果表明，通过共价键或机械混合方式引入三嗪环可以在不破坏原有骨架的情况下显著提高光催化剂的性能。在自然阳光照射下，仅以水和空气为原料，H2O2的生成速率可提高约4.3倍。综合实验表征，包括表面光电压和原位电子顺磁共振，以及理论计算证明了三嗪环的共催化性质。这些环有效地使光激发电子离域，促进了吸附O2的还原，提高了H2O2的生成。值得注意的是，在保持底层框架完整的情况下，在催化剂基体中战略性地结合三嗪环，这强调了这种方法被外推到更广泛的有机光催化剂的潜力。这一创新策略不仅为提高催化性能铺平了道路，而且体现了分子设计在催化领域的多功能性和适应性。
Figure 1. Preparation and performance of AOF-N. (a) Schematic illustration of the synthesis and chemical structures of AOF and AOF-N. (b) UV−visible absorption diffuse reflectance spectra of AOF and AOF-N (inset: energy band diagrams). (c) Reaction setup for the natural sunlightdriven photosynthesis of H2O2. (d) Photocatalytic H2O2 production performance over AOF and AOF-N. Reaction conditions: catalyst (50 mg), H2O (200 mL), nature sunlight, and the average sunlight intensity: 19.3 mW cm−2.
Figure 2. Structural characterization of AOF-N. (a) FT-IR spectra. (b) Solid-state 13C CP/MAS NMR spectra. (c) TEM and EDX mapping images of AOF-N. (d) Contact angle of AOF-N and photographs of AOF-N dispersed on the surface of the water.
Figure 3. Photocatalytic H2O2 production performance. (a) Photocatalytic activity of catalysts prepared with different CC to TPB ratios. Reaction conditions: AOF-N (200 mg), H2O (200 mL), 288 K, 300 W Xe lamp, and λ > 420 nm. (b) Photocatalytic activity of catalysts obtained by mechanically mixing AOF with different amounts of triazine groups. Reaction conditions: AOF (200 mg) and CC of different qualities (20, 30, and 50 mg), H2O (200 mL), 288 K, 300 W Xe lamp, and λ > 420 nm. (c) Long-term photocatalytic cycling experiments of AOF-N. Reaction conditions: AOF-N (200 mg), H2O (200 mL), 288 K, 300 W Xe lamp, and λ > 420 nm. (d) Photocatalytic H2O2 production over AOF-N in pure water at different pH. Reaction conditions: AOF-N (200 mg), H2O (200 mL), 288 K, 300 W Xe lamp, and λ > 420 nm. (e) Schematic diagram of bacterium inactivation using H2O2 generated by AOF-N. (f) Photocatalytic sterilization performances toward Gram-positive methicillin-resistant Staphylococcus aureus under visible-light irradiation.
Figure 4. Insights into the role of the triazine ring as a cocatalyst. (a) ESP and the frontier molecular orbital distribution for model compounds. (b) SPV signal. (c) EPR spectra taken in dark and under light irradiation. (d) EPR spectra of DMPO-•O2 −. (e) Mechanism for photocatalytic H2O2 production on the AOF-N.
Triazine Ring-Enhanced Transient-State Self-Bipolarized Organic Frameworks for Natural Sunlight-Driven H2O2 Photosynthesis
https://doi.org/10.1021/acscatal.4c02285
