Szalad Horaţiu, Uscategui-Linares Andrés, García-Muelas Rodrigo, Galushchinskiy Alexey, Savateev Oleksandr, Antonietti Markus, Albero Josep, García Hermenegildo
Instituto Universitario de Tecnología Química (CSIC-UPV), Universitat Politècnica de València, Avda. de los Naranjos s/n, Valencia 46022, Spain.
Max Planck Institute of Colloids and Interfaces (MPIKG), Research Campus Golm, Potsdam D-14424, Germany.
ACS Appl Mater Interfaces. 2024 Dec 11;16(49):67597-67608. doi: 10.1021/acsami.4c12548. Epub 2024 Nov 29.
tetrakis(4-carboxyphenyl)porphyrin (HTCPP) has been loaded on a partially exchanged Zn poly(heptazine imide) (PHI), changing the light harvesting properties of the system, without altering the PHI structure. At the optimal loading (20 wt %), the photosensitized (Zn/K)-PHI is able to produce 1.06 mmol/g and 0.46 mmol/g after 12 h of reaction irradiation of Milli-Q water under visible light by a 100 mW/cm white LED. The apparent quantum yield for the overall water splitting reaction was 5.5% at 400 nm and 2% at 700 nm. Outdoor water splitting irradiation with natural sunlight shows the feasibility of the process. The photocatalytic performance of TCPP20%@(Zn/K)-PHI is considerably higher than that of analyzed reference samples such as graphitic carbon nitride, poly(triazine imide), and potassium PHI with HTCPP photosensitization. These relative photocatalytic activities point out the relevance of the PHI structure and the presence of Zn. It is proposed that Zn simultaneously binds PHI and HTCPP. Transient absorption spectroscopy supports the occurrence of photoinduced electron transfer in which electrons are located at the HTCPP and holes at the PHI moiety. Transient photocurrent measurements show a higher charge separation efficiency on TCPP20%@-(Zn/K)-PHI compared to (Zn/K)-PHI, and measurement of the frontier orbitals indicates an adequate energy alignment of the HOMO/LUMO levels of TCPP with respect to (Zn/K)-PHI. The results show the possibility of developing efficient noble metal-free photocatalytic systems based on PHI dye sensitization.
四（4-羧基苯基）卟啉（HTCPP）负载于部分交换的锌聚（七嗪酰亚胺）（PHI）上，在不改变PHI结构的情况下改变了该体系的光捕获性能。在最佳负载量（20 wt%）下，经100 mW/cm的白色发光二极管在可见光下对超纯水进行12小时的反应辐照后，光敏化的（Zn/K）-PHI能够产生1.06 mmol/g和0.46 mmol/g的产物。在400 nm处，整体水分解反应的表观量子产率为5.5%，在700 nm处为2%。利用自然阳光进行户外水分解辐照表明了该过程的可行性。TCPP20%@（Zn/K）-PHI的光催化性能明显高于经分析的参考样品，如石墨相氮化碳、聚（三嗪酰亚胺）以及经HTCPP光敏化的钾PHI。这些相对的光催化活性表明了PHI结构和锌的存在的相关性。有人提出锌同时与PHI和HTCPP结合。瞬态吸收光谱法支持了光致电子转移的发生，其中电子位于HTCPP上，空穴位于PHI部分。瞬态光电流测量表明，与（Zn/K）-PHI相比，TCPP20%@-（Zn/K）-PHI具有更高的电荷分离效率，并且前沿轨道的测量表明TCPP的HOMO/LUMO能级相对于（Zn/K）-PHI具有合适的能量排列。结果表明了基于PHI染料敏化开发高效无贵金属光催化体系的可能性。
