多金属氧酸盐催化的水氧化研究进展

Progress in Polyoxometalates-Catalyzed Water Oxidation

氢气以其清洁无污染、燃烧值高等优点成为未来最具潜力的可再生能源之一,而清洁生产氢气的最佳选择之一即为裂解水.利用太阳能模拟光合作用实现水的全分解产生氢气和氧气是目前最为理想的能源转化方式,并且已经引起了众多研究者的关注.水分解的半反应之一——水氧化反应由于其过程复杂,一直是制约水分解的瓶颈.所以寻找高效、稳定的水氧化催化剂便成为了突破该瓶颈的关键.多金属氧酸盐是一类以前过渡金属氧簇为基本单元形成的多金属氧簇化合物.由于多金属氧酸盐在物理、化学性质方面具有无法比拟的特性,使得其在催化、药物、纳米科技和材料科学等方面已被广泛地应用.多金属氧酸盐的全无机配体可很好地抵御水氧化反应的强氧化性环境,故将其作为水氧化催化剂越来越引起研究者们的注意,并且已有多种多金属氧酸盐被设计为水氧化催化剂.本文详细介绍了各种不同过渡金属取代的多金属氧酸盐水氧化催化剂的研究进展.

H2 is considered to be a clean, efficiently and renewable energy because H2O is the only product when H2 combines with O2. The splitting of water into HE and O2 by sunlight is viewed as one of the most promising ways to produce clean and sustainable energy that is expected to meet the future need as environmentally friendly and renewable energy sources. Artificial photosynthesis water splitting is currently the most ideal energy conversion mode, and it has attracted many researchers＇ interest. Through this way, H2 can be separated from reaction system or in-situ used when a solar cell designed together. Water oxidation is identified as the bottleneck of water splitting because it requires a multi-electron stepwise building up of very high redox potentials. So, development of efficient and stable water oxidation catalysts （WOCs） is the key step in overall water splitting. Polyoxometalates （POMs） are a versatile family of early transition-metal oxide nanoclusters. Owing to the unmatched physical and chemical properties of POMs, they have been widely applied in catalysis, medicine, nanotechnology and materials science. Development of POMs as WOCs has given rise to more and more interesting of researchers because the all-inorganic ligands of POMs can resist the strong oxidizing environment of water oxidation reaction, which is a shortcoming of many organometallic complex WOCs. POMs have the nature between metal oxides and molecular catalysts （the so-called molecular metal oxide）, thus, this kind of WOC combines the stability benefit of heterogeneous WOCs and other molecular benefits of homogeneous WOCs, which give rise to the attention of researchers. Based on a considerable number of POMs have been designed as WOCs so far, it is necessary to carry on a review for previous POM-WOCs work. In this review, various different type transition metal substituted POMs as WOCs were described and commented in detail.