Ruan Xiaowen, Meng Depeng, Xu Minghua, Fang Guozhen, Ding Chunsheng, Leng Jing, Wang Xuan, Ba Kaikai, Zhang Haiyan, Zhang Wei, Xie Tengfeng, Jiang Zhifeng, Dai Jianan, Cui Xiaoqiang, Ravi Sai Kishore
School of Energy and Envionment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, 999077, P. R. China.
National Key Laboratory of Automotive Chassis Integration and Bionics, School of Materials Science and Engineering, Key Laboratory of Automobile Materials of MOE, Jilin Provincial International Cooperation Key Laboratory of High-Efficiency Clean Energy Materials, Electron Microscopy Center, Jilin University, 2699 Qianjin Street, Changchun, 130012, P. R. China.
Adv Sci (Weinh). 2025 Apr;12(15):e2501037. doi: 10.1002/advs.202501037. Epub 2025 Feb 22.
Natural photosynthetic systems utilize complex pigment-protein assemblies for light harvesting across a broad spectral range from UV to near-infrared, enabling efficient photogeneration and charge separation. Conventional photocatalysts, however, primarily absorb UV (<380 nm) and visible light (380-780 nm), resulting in suboptimal spectral utilization. This study introduces a semi-organic artificial photosynthetic system that integrates molecularly engineered phenoxazinone derivatives with H-doped rutile TiO (H-TiO) nanorods. Bis(Triphenylamine)Phenoxazinone (BTP) features a phenoxazinone core with two triphenylamine donor groups, enabling light absorption up to 800 nm. Modifying BTP with an additional malononitrile group (MBTP) extends absorption into the NIR region up to 1200 nm. Optimized semi-organic catalysts with MBTP nanobelts and H-TiO nanorods showed an excellent photocatalytic hydrogen evolution rate of 29.4 mmol g h and 60.4 µmol g h under UV-vis and NIR irradiation, respectively. Femtosecond transient absorption (fs-TA) spectroscopy showed rapid electron injection from the photoexcited phenoxazinone derivatives to the H-TiO conduction band, indicating efficient charge carrier dynamics. Photoelectrochemical measurements confirmed improved charge transport and reduced recombination in the MBTP-based system, attributed to the stronger internal electric field and increased dipole moment from the malononitrile modification. These findings highlight the potential of tailored semi-organic systems for high-efficiency solar-to-hydrogen conversion.
天然光合系统利用复杂的色素 - 蛋白质组装体在从紫外到近红外的宽光谱范围内进行光捕获，从而实现高效的光生和电荷分离。然而，传统的光催化剂主要吸收紫外光（<380 nm）和可见光（380 - 780 nm），导致光谱利用率欠佳。本研究引入了一种半有机人工光合系统，该系统将分子工程化的吩恶嗪酮衍生物与H掺杂的金红石TiO₂（H-TiO₂）纳米棒相结合。双（三苯胺）吩恶嗪酮（BTP）具有一个带有两个三苯胺供体基团的吩恶嗪酮核心，能够吸收高达800 nm的光。用额外的丙二腈基团修饰BTP（MBTP）可将吸收扩展到近红外区域，直至1200 nm。含有MBTP纳米带和H-TiO₂纳米棒的优化半有机催化剂在紫外 - 可见光和近红外光照射下分别显示出优异的光催化析氢速率，分别为29.4 mmol g⁻¹ h⁻¹和60.4 μmol g⁻¹ h⁻¹。飞秒瞬态吸收（fs-TA）光谱表明，光激发的吩恶嗪酮衍生物向H-TiO₂导带的电子注入迅速，这表明电荷载流子动力学高效。光电化学测量证实，基于MBTP的系统中电荷传输得到改善，复合减少，这归因于丙二腈修饰产生的更强内部电场和增加的偶极矩。这些发现突出了定制半有机系统在高效太阳能到氢能转换方面的潜力。
