Recently, Li Can, academician of the Chinese Academy of Sciences, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, and researcher Zhang Fuxiang, etc., have made new progress in the research of hydrogen production from hydrogen by fully decomposing water with a broad-spectrum light-harvesting catalyst Z mechanism. The results of the study found that by designing and regulating the loading of Au on the BiVO4 surface co-catalyst and the selective loading of dual co-catalysts (Au and CoOx), the oxygen-generating performance of BiVO4 and its charge with redox ion pairs can be effectively promoted Transmission, and based on this, an efficient visible light Z mechanism fully decomposed water system was constructed, and its apparent quantum efficiency exceeded 10% (420nm excitation). Related results were published online in the Joule journal under Cell.
The realization of total solar energy decomposition of water and hydrogen production based on the photocatalyst powder suspension system is expected to become one of the economically feasible solar energy conversion methods. In recent years, the team of Li Can and Zhang Fuxiang has been committed to constructing a Z-mechanism fully decomposed water system using broad-spectrum response materials. During this period, a new method of “one pot nitridation†to construct a heterojunction to promote charge separation was developed, The experimental difficulty of poor thermal stability under air or inert gas is not easy to construct a heterojunction, and then a number of Z-mechanism total decomposition water hydrogen production systems (Angew. Chem. Int. Ed., Chem. Sci.) Are constructed. In addition, the team developed a new method for the protection of the loaded oxygen-release cocatalyst with ammonia gas flow, which greatly improved the oxygen release performance of the broad-spectrum light-harvesting catalyst; on this basis, it was also found that the dispersibility of the cocatalyst has a great effect on the interface charge separation It is affected by the hydrophilic and hydrophobic properties of the interface. For example, the modification of the magnesium oxide layer on the surface of Ta3N5 can not only promote the dispersion of the cocatalyst and the separation efficiency of the interface charge, but also effectively suppress the competitive reaction in the Z mechanism, and finally decompose the Z mechanism. Hydrogen production is possible (relevant results are published in J. Am. Chem. Soc., Angew. Chem. Int. Ed., J. Catal., Appl Catal B: Environ., Etc.). Through continuous efforts, the team has not only successfully expanded the visible light utilization range of the hydrogen production and oxygen production end catalysts in the Z mechanism of fully decomposed water (hydrogen production end expanded from 510nm to 650nm; oxygen production end expanded from 450nm to 590nm), and The apparent quantum efficiency record of the hydrogen mechanism catalyzed by the complete decomposition of water in the Z mechanism of the powder system is continuously updated.
The study used [Fe (CN) 6] 3-/ [Fe (CN) 6] 4-, which has a single electron transfer, is suitable for a neutral environment, and has a low redox potential, as a redox couple, based on its previous experimental findings , There is space separation of photogenerated electrons and holes between different crystal planes of BiVO4 (Nature Commun.), And the selective deposition strategy of dual co-catalysts (Au / CoOx) on the {010} and {110} crystal planes of BiVO4 makes oxygen production The performance has been greatly improved. On this basis, by coupling the hydrogen-producing end with a wider visible light response, an efficient Z-mechanism fully decomposed water was achieved, and a quantum efficiency of 10.3% (420 nm excitation) of fully decomposed water to produce hydrogen was achieved, refreshing the team ’s previous maintenance. 6.8% (420nm excitation) record. In addition, the study also found that the loading of Au nanoparticles is conducive to the transfer of electron extraction from BiVO4 to [Fe (CN) 6] 3-. The above research results laid the foundation for further development of highly efficient visible light complete water splitting system in the future.
The research work was supported by the Fund Committee, the Ministry of Science and Technology, the Chinese Academy of Sciences and the Collaborative Innovation Center for Energy Materials Chemistry.
Masking Tape Replacement Roller
PRO-CHARGER CO., LTD. (VICTOR HERO HOLDINGS LTD, TIME VALUE LTD.) , https://www.pro-chargerco.com