Design of a highly efficient photoelectrolytic cell for hydrogen generation by water splitting:: Application of TiO2-xCx nanotubes as a photoanode and Pt/TiO2 nanotubes as a cathode
Design of a highly efficient photoelectrolytic cell for hydrogen generation by water splitting:: Application of TiO2-xCx nanotubes as a photoanode and Pt/TiO2 nanotubes as a cathode
复制标题
DOI：
10.1021/jp071906v
复制
发表时间：
2007-06-21
影响因子：
3.7
通讯作者：
Raja, Krishnan S.
中科院分区：
文献类型：
--
作者：
Mohapatra, Susanta K.;Misra, Mano;Raja, Krishnan S.
设计了一种以碳掺杂二氧化钛（TiO 2-xCx）纳米管阵列为光阳极，以Pt、Pt纳米粒子为阴极的光电化学电池。发现PEC电池是高效的（即，在低外部偏压下提供良好的光电流，j（p）= 2.5-2.8 mA/cm（2），-0. 4V-Ag/AgCl），价格低廉（TiO 2上仅含0.4wt% Pt），并且对于模拟太阳强度照射下水分解制氢具有鲁棒性（连续运行80小时而不影响光电流）。该光阳极的合成是通过声电化学阳极氧化技术使用乙二醇和氟化铵水溶液进行的。这种阳极氧化工艺可以得到自组织的六方有序的TiO 2纳米管阵列，具有广泛的纳米管结构，具有良好的均匀性和一致性。合成的二氧化钛纳米管在还原气氛（H-2）下退火，这将无定形纳米管阵列转化为光活性的纳米晶相，并且它有助于掺杂碳（来自乙二醇的还原）以得到TiO 2-xCx型光阳极。阴极材料通过用初湿含浸法将Pt纳米颗粒（通过将Pt盐还原成Pt（0））合成到二氧化钛纳米管阵列中来制备。各种表征技术，即，场发射扫描电子显微镜、能量色散谱、X射线光电子能谱、高分辨率透射电子显微镜、电子衍射和掠射角X射线衍射等，用于研究纳米管的形貌、物相、带隙和掺杂。
This paper describes the design of a photoelectrochemical (PEC) cell using carbon-doped titanium dioxide (TiO2-xCx) nanotube arrays as the photoanode and platinum, Pt nanoparticles incorporated in TiO2 (titania) nanotube arrays, as the cathode. The PEC cell is found to be highly efficient (i.e., gives good photocurrent at a low external bias, j(p) = 2.5-2.8 mA/cm(2) at -0.4 V-Ag/AgCl), inexpensive (only 0.4 wt % Pt on TiO2), and robust (continuously run for 80 h without affecting the photocurrent) for hydrogen generation by water splitting under the illumination of simulated one sun intensity. The synthesis of the photoanode is carried out by the sonoelectrochemical anodization technique using aqueous ethylene glycol and ammonium fluoride solution. This anodization process gives self-organized hexagonally ordered TiO2 nanotube arrays with a wide range of nanotube structure, which possess good uniformity and conformability. As-synthesized titania nanotubes are annealed under reducing atmosphere (H-2), which converts the amorphous nanotube arrays to photoactive anatase phase as well as it helps in doping of the carbon (from the reduction of ethylene glycol) to give the TiO2-xCx type photoanode. The cathode material is prepared by synthesizing Pt nanoparticles (by reduction of a Pt salt to Pt(0)) into the titania nanotubular arrays by the incipient wetness method. Various characterization techniques, viz., field emission scanning electron microscopy, energy dispersive spectroscopy, X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, electron diffraction, and glancing angle X-ray diffraction, etc., are used to study the morphology, phase, band gap, and doping of the nanotubes.