Department of Chemistry, Faculty of Sciences, Kyushu University, Hakozaki 6-10-1, Higashi-ku, Fukuoka, 812-8581 (Japan); International Institute for Carbon-Neutral Energy Research (WPI-I2CNER), Kyushu University (Japan).
Angew Chem Int Ed Engl. 2014 Apr 25;53(18):4618-22. doi: 10.1002/anie.201311209. Epub 2014 Mar 28.
In order to solve the problems of global warming and shortage of fossil fuels, researchers have been endeavoring to achieve artificial photosynthesis: splitting water into H2 and O2 under solar light illumination. Our group has recently invented a unique system that drives photoinduced water reduction through "Z-scheme" photosynthetic pathways. Nevertheless, that system still suffered from a low turnover number (TON) of the photocatalytic cycle (TON=4.1). We have now found and describe herein a new methodology to make significant improvements in the TON, up to around TON=14-27. For the new model systems reported herein, the quantum efficiency of the second photoinduced step in the Z-scheme photosynthesis is dramatically improved by introducing multiviologen tethers to temporarily collect the high-energy electron generated in the first photoinduced step. These are unique examples of "pigment-acceptor-catalyst triads", which demonstrate a new effective type of artificial photosynthesis.
为了解决全球变暖和化石燃料短缺的问题，研究人员一直在努力实现人工光合作用：在太阳光照射下将水分解为 H2 和 O2。我们小组最近发明了一种独特的系统，通过“Z 型”光合作用途径驱动光诱导水还原。然而，该系统的光催化循环的周转数（TON）仍然较低（TON=4.1）。我们现在发现并描述了一种新方法，可以将 TON 显著提高到约 TON=14-27。对于本文报道的新模型系统，通过引入多联吡啶鎓 tether 来暂时收集在第一光诱导步骤中产生的高能电子，显著提高了 Z 型光合作用中第二光诱导步骤的量子效率。这些是“色素-受体-催化剂三联体”的独特示例，展示了一种新型有效的人工光合作用。
