Insights into the multirole CoAl layered double hydroxide on boosting photoelectrochemical activity of hematite: Application to hydrogen peroxide sensing.
Insights into the multirole CoAl layered double hydroxide on boosting photoelectrochemical activity of hematite: Application to hydrogen peroxide sensing.
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DOI：
10.1016/j.talanta.2023.124681
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发表时间：
2023-05
期刊：
影响因子：
6.1
通讯作者：
Jiaqi Lv;Mingwei Wu;Ming Fan;Q. Zhang;Zhixian Chang;Xinshou Wang;Qian Zhou;Li Wang;R. Cho
中科院分区：
文献类型：
--
作者：
Jiaqi Lv;Mingwei Wu;Ming Fan;Q. Zhang;Zhixian Chang;Xinshou Wang;Qian Zhou;Li Wang;R. Cho
过氧化氢（H2O2）是许多工业和生物过程中的重要化合物，高浓度时会对人体健康造成危害。因此，开发高灵敏度、高选择性的传感器用于水质监测、食品质量控制等领域的实际h2o2检测迫在眉睫。本文采用简单的水热法制备了装饰赤铁矿（CoAl- ldh /α-Fe2O3）的煤层状双氢氧化物超薄纳米片光电极。煤- ldh /α- fe2o3具有较宽的线性范围（1 ~ 2000 μM），高灵敏度为132.0 μA mM−1cm−2，低检出限为0.04 μM (S/N≥3)，优于文献中基于α- fe2o3的传感器。利用电化学阻抗谱、Mott-Schottky图、循环伏安法、开路电位和强度调制光电流谱等（光）电化学表征方法，研究了煤- ldh对α- fe2o3对H2O2的PEC响应的改善作用。结果表明，煤- ldh不仅可以钝化α-Fe2O3的表面态，扩大α-Fe2O3的能带弯曲，还可以作为空穴的俘获中心，继而作为h2o2氧化的活性位点，从而促进电荷的分离和转移。提高脉冲电场响应的策略将有助于半导体脉冲电场传感器的进一步发展。
As an important compound in many industrial and biological processes, hydrogen peroxide (H2O2) would cause harmfulness to human health at high concentration level. It thus is urgent to develop highly sensitive and selective sensors for practical H2O2detection in the fields of water monitoring, food quality control, and so on. In this work, CoAl layered double hydroxide ultrathin nanosheets decorated hematite (CoAl-LDH/α-Fe2O3) photoelectrode was successfully fabricated by a facile hydrothermal process. CoAl-LDH/α-Fe2O3displays the relatively wide linear range from 1 to 2000 μM with a high sensitivity of 132.0 μA mM−1cm−2and a low detection limit of 0.04 μM (S/N ≥ 3) for PEC detection of H2O2, which is superior to other similar α-Fe2O3-based sensors in literatures. The (photo)electrochemical characterizations, such as electrochemical impedance spectroscopy, Mott-Schottky plot, cyclic voltammetry, open circuit potential and intensity modulated photocurrent spectroscopy, were used to investigate the roles of CoAl-LDH on the improved PEC response of α-Fe2O3toward H2O2. It revealed that, CoAl-LDH could not only passivate the surface states and enlarge the band bending of α-Fe2O3, but also could act as trapping centers for holes and followed by as active sites for H2O2oxidation, thus facilitated the charge separation and transfer. The strategy for boosting PEC response would be help for the further development of semiconductor-based PEC sensors.