文献速递|湖南农业大学CEJ:洞察双Z型和压电性共同驱动的光催化剂，用于超速降解烯啶虫酰胺

第一作者：Sheng Xiong

通讯作者：邓垚成 教授/Daoxin Gong

通讯单位：湖南农业大学资源与环境学院

DOI:10.1016/j.cej.2022.138399

在此，我们选择了AgI、Ag3PO4和BaTiO3来构建一个双Z-scheme催化剂。据我们所知，Ag3PO4都具有优良的光催化性能和严重的光腐蚀。所以选择了AgI和BaTiO3来合成异质结进行保护。此外，AgI、Ag3PO4和BaTiO3的带状结构适合于理论上构建双Z-scheme。此外，BaTiO3具有很强的铁电性和压电性，引入它有利于压电光催化性能。因此，本工作报告了一种简单的一锅式制备AgI/Ag3PO4/BaTiO3复合材料的方法，由于双Z-scheme和压电性的协同作用，该材料具有超速降解NTP的功能。在最佳条件下，所制备的三元复合材料在10分钟内对NTP的去除率高达100%，AgI/Ag3PO4/BaTiO3的表观速率常数（kapp）是最佳二元材料Ag3PO4/BaTiO3的2.12倍。与其他光催化剂相比，这项工作表现出优异的NTP去除率。随后，材料表征验证了AgI/Ag3PO4/BaTiO3复合材料中电子-电洞分离和电荷转移性能的增强。这项工作为进一步发展压电光催化技术、促进光诱导的电子-空穴分离以及同时利用机械能和光能提供了一个有效的解决方案。

Fig. 1. a) XRD pattern of prepared materials. SEM images of b) AgI, c) Ag3PO4, d) BaTiO3 and e) AgI/Ag3PO4/BaTiO3 sample. f) TEM images of AgI/Ag3PO4/BaTiO3 sample at 100 nm and g) the lattice of AgI, BaTiO3, and Ag3PO4, h) Height sensor topography of AgI/Ag3PO4/BaTiO3, the insert is the height profile of the yellow line. i) HAADF-STEM image and corresponding EDS mapping profiles for Ag, I, O, P, Ba, and Ti.Fig. 2. a) PL spectra, b) transient photocurrent responses, c) EIS analysis, d) LSV curves and e) UV–vis diffuse reflectance spectra of all prepared materials. f) Mott-Schottky plots of AgI, Ag3PO4 and BaTiO3. UPS spectra for g) AgI, h) Ag3PO4 and i) BaTiO3.Fig. 3. NTP removal by prepared materials at different condition: a) piezocatalysis, b) photocatalysis and c) piezo-photocatalysis. d, e, f) The related kapp of prepared materials under different conditions. Comparison of g) NTP removal rate, and h) kapp of prepared materials under different conditions. i) Piezo-photocatalytic performance comparison different material (insert is the related kapp). [the molar ratio of AgI: Ag3PO4: BaTiO3 = 2: 3: 2,], [the molar ratio of AgI/Ag3PO4:BaTiO3 = 5: 2]. [NTP] = 5 mg/L, [Catalyst] = 10 mg, [pH] = 6.11.Fig. 4. a) The result of the quenching experiment on NTP degradation by AgI/Ag3PO4/BaTiO3 and b) related kapp. EPR detect of c) hydroxyl radicals, d) singlet oxygen, and e) superoxide radical. XPS high-resolution f) P 2p, g) I 3d, h) Ba 3d and i) Ti 2p spectra of Ag3PO4, AgI, BaTiO3 and AgI/Ag3PO4/BaTiO3 photocatalysts.Fig. 5. Ferroelectricity and piezoelectricity of AgI/Ag3PO4/BaTiO3 as studied with piezoresponse force microscopy. The 3D images of a) topography, b) amplitude, c) phase after the Gwyddion process. d) Piezoresponse amplitude-voltage, and e) phase-voltage curves. COMSOL simulation for the piezoelectric potential distribution in BaTiO3 nanocrystals: f) nanocube, g) nanostrip and h) nanosheet.Scheme 2. Possible mechanism of a) NTP removal by dual Z-scheme photocatalyst and b) the promotion effect by piezoelectricity of BaTiO3.Fig. 6. (a) The charge density difference (0.0015 e•Å-3) for BaTiO3/Ag3PO4. (b) Planar-averaged electron density difference ∆ρ(z) for BaTiO3/Ag3PO4. The yellow and cyan areas indicate electron accumulation and depletion, respectively.Fig. 7. Possible pathways proposed for NTP degradation by the piezo-photocatalysis of AgI/Ag3PO4/BaTiO3.