National Synchrotron Radiation Laboratory, University of Science and Technology of China, 42# HeZuoHua Road, Hefei, Anhui 230029, China.
1] National Synchrotron Radiation Laboratory, University of Science and Technology of China, 42# HeZuoHua Road, Hefei, Anhui 230029, China [2] Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei 230026, China.
Nat Commun. 2014 Oct 6;5:5122. doi: 10.1038/ncomms6122.
There remains a pressing challenge in the efficient utilization of visible light in the photoelectrochemical applications of water splitting. Here, we design and fabricate pseudobrookite Fe2TiO5 ultrathin layers grown on vertically aligned TiO2 nanotube arrays that can enhance the conduction and utilization of photogenerated charge carriers. Our photoanodes are characterized by low onset potentials of ~0.2 V, high photon-to-current efficiencies of 40-50% under 400-600 nm irradiation and total energy conversion efficiencies of ~2.7%. The high performance of Fe2TiO5 nanotube arrays can be attributed to the anisotropic charge carrier transportation and elongated charge carrier diffusion length (compared with those of conventional TiO2 or Fe2O3 photoanodes) based on electrochemical impedance analysis and first-principles calculations. The Fe2TiO5 nanotube arrays may open up more opportunities in the design of efficient and low-cost photoanodes working in visible light for photoelectrochemical applications.
在光解水的光电化学应用中，有效利用可见光仍然面临着紧迫的挑战。在这里，我们设计并制造了在垂直排列的 TiO2 纳米管阵列上生长的赝金红石 Fe2TiO5 超薄层，这可以增强光生载流子的传导和利用。我们的光阳极的特征在于，在 400-600nm 辐射下，起始电位约为 0.2V，光子-电流效率高达 40-50%，总能量转换效率约为 2.7%。Fe2TiO5 纳米管阵列的高性能归因于基于电化学阻抗分析和第一性原理计算的各向异性电荷载流子输运和延长的电荷载流子扩散长度（与传统的 TiO2 或 Fe2O3 光阳极相比）。Fe2TiO5 纳米管阵列可能为可见光下工作的高效、低成本光阳极的设计开辟更多机会，用于光电化学应用。
