Synthesis of lanthanide-doped titanium-oxo clusters for efficient photocurrent responses

Abstract

Incorporation of lanthanide atom into the titanium−oxo cluster structure is an effective strategy for exploring novel photoelectrode materials. Herein, we synthesized and characterized three lanthanide-doped titanium−oxo clusters (Ln-TOCs): [Ti4La(μ3-O)3(OiPr)2(C6H5COO)11]·3CH3CN (1), [Ti4Eu2(μ3-O)4(acac)2(C6H5COO)13] (2, acac ​= ​acetylacetonate), and [Ti7Ce(μ2-O)2(μ3-O)5(OiPr)2(C6H5COO)15]·CH3CN (3). These Ln−TOCs display strong UV-light absorption and extended visible light absorption, which can be ascribed to the doping of lanthanides and benzoates. As electrode precursors for photoelectric responses, these Ln doped clusters exhibit clear photocurrent responses. Moreover, cluster 3 shows the highest photocurrent intensity because of Ce(IV)/Ce(III) redox reaction. This work not only enriches the Ln−TOCs family, but also promotes the development of novel titanium-based photoelectric active materials.