Enhanced Solar Water Splitting by Swift Charge Separation in Au/FeOOH Sandwiched Single-Crystalline Fe2O3 Nanoflake Photoelectrodes
Enhanced Solar Water Splitting by Swift Charge Separation in Au/FeOOH Sandwiched Single-Crystalline Fe2O3 Nanoflake Photoelectrodes
复制标题
通过 Au/FeOOH 夹层单晶 Fe2O3 纳米片光电极中的快速电荷分离增强太阳能水分解
DOI：
10.1002/cssc.201700522
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发表时间：
2017-07-10
期刊：
影响因子：
8.4
通讯作者：
Schmuki, Patrik
中科院分区：
文献类型：
--
作者：
Wang, Lei;Nhat Truong Nguyen;Schmuki, Patrik
在这项工作中，单晶 α-Fe2O3 纳米片 (NF) 通过热氧化技术在 Fe 基底上接种 Au 形成高密度阵列。 NFs 共形地装饰有一层薄薄的 FeOOH 助催化剂层。光电化学 (PEC) 测量表明，与 Fe 基底上的普通 α-Fe2O3 纳米结构相比，这种光电阳极采用基于 Au/Fe 结构的 α-Fe2O3/FeOOH NF，表现出显着增强的 PEC 水氧化性能。 Au/Fe光阳极上的a-Fe2O3/FeOOH NF在AM 1.5G（00 mWcm（-2））模拟太阳光照射下，在1m KOH中产生3.1 mA cm（-2）的光电流密度和0.5-0.6 V-RHE的非常低的起始电位。 PEC性能的增强可归因于FeOOH顶部装饰和Au底层的协同效应，其中FeOOH促进电极/电解质界面处的空穴传输，而Au层为电子传输到背接触提供了接收器。这使得单晶 α-Fe2O3 NF 光电阳极的电荷分离效率显着提高。
In this work, single crystalline alpha-Fe2O3 nanoflakes (NFs) are formed in a highly dense array by Au seeding of a Fe substrate by a thermal oxidation technique. The NFs are conformally decorated with a thin FeOOH cocatalyst layer. Photoelectrochemical (PEC) measurements show that this photoanode, incorporating alpha-Fe2O3/ FeOOH NFs rooted on the Au/Fe structure, exhibits significantly enhanced PEC water oxidation performance compared to the plain alpha-Fe2O3 nanostructure on the Fe substrate. The a-Fe2O3/ FeOOH NFs on Au/Fe photoanode yields a photocurrent density of 3.1 mA cm(-2) a remarkably low onset potential of 0.5- 0.6 V-RHE in 1m KOH under AM 1.5G (00 mWcm(-2)) simulated sunlight illumination. The enhancement in PEC performance can be attributed to a synergistic effect of the FeOOH top decoration and the Au underlayer, whereby FeOOH facilitates hole transfer at the interface of electrode/electrolyte and the Au layer provides a sink for the electron transport to the back contact. This results in a drastically improved charge-separation efficiency in the single crystalline alpha-Fe2O3 NF photoanode.