本文研究课题“碘催化氯苯的氯代反应”来源于2021年全国统考高考化学试卷(浙江卷)的考题，其试题背后隐含了一系列化学基本概念和基本理论。前期文献对该题目进行了研究，所得结果与高考题目中的描述不一致。本文用密度泛函理论(DFT)方法重新对该反应进行了系统研究，确立了反应的催化活性组分及其形成机理，计算了氯苯氯代反应的分子机制、反应的热力学和动力学性质，比较了邻位、间位及对位取代的反应性能，分析了电子效应和空间效应对反应性能的影响。本文计算结果与高考题目中的描述一致，表明了该题目的严谨性和科学性。本文研究结果有助于学生加深对芳香化合物亲电取代反应的认识和理解。

采用原位聚合法制备了氯氧化铋(BiOCl)与聚苯胺(PANI)复合的Ⅱ型异质结光催化剂BiOCl/PANI，并采用X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)、紫外可见漫反射光谱(UV-Vis DRS)和N2吸附-脱附测试等多种技术手段对其进行了表征，考察了BiOCl/PANI在模拟可见光下对罗丹明B (RhB)的光催化降解性能。实验结果表明：BiOCl/PANI催化剂比PANI和BiOCl具有更高的光催化活性，在RhB质量浓度为50 mg·L^-1、PANI与BiOCl的物质的量之比为0.02∶1、50 mg·L^-1的催化剂条件下，所制备的BiOCl/PANI光催化150 min后，RhB降解率为98.8%，速率常数为0.031 min^-1；经过4次循环实验后，RhB降解率从98.8%降低至98.4%，表现出良好的稳定性和可重复利用性。光催化剂BiOCl/PANI实现了电子和空穴对的快速分离，降低了二者在催化剂内部的复合速率，提高了光催化性能。

仪器分析实验“分子荧光法测定罗丹明B的含量”存在实验过于简单、未考虑实际情况等问题。因此，本改进实验在三维荧光扫描模式下获取样本数据，不进行复杂预处理，而是运用化学计量学算法解析出目标分析物的纯信号，进而实现了染色辣椒中罗丹明6G和123的同时测定。本改进实验提高了学生全面考虑问题和创新解决问题的能力。

A simple two-step hydrothermal method synthesized four different CdS/Fe₃O₄ photocatalysts with varying ratios of mass of CdS to Fe₃O₄. The composition and morphology of the prepared samples were investigated using X-ray diffraction (XRD), Raman spectrum, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Solid UV reflectance spectra testing found that CdS/Fe₃O₄ nanocomposites had good light absorption throughout the spectral range, promoting their photocatalytic properties. Under visible light irradiation, CdS/Fe₃O₄ (2:5) with a mass ratio of 2:5 exhibited excellent photocatalytic performance, with a degradation rate of 98.8% for rhodamine B. Furthermore, after five cycles of photocatalytic degradation reaction, the rhodamine B degradation rate remained at 96.2%, indicating that the photocatalysts have good photocatalytic stability.

A flower-like BiOBr photocatalyst (CS/BiOBr) was prepared by using the carbon material derived from corn straw (CS) as the carrier. The prepared composites were characterized by X - ray diffraction (XRD), Fourier transform infrared (FIIR) spectra, scanning electron microscope (SEM), X - ray photoelectron spectra (XPS), and UV-Vis diffuse reflectance spectra (UV-Vis DRS). The SEM analyses indicate that the introduction of CS promotes the formation of a unique flower-like structure in BiOBr, which not only optimizes the efficiency of light capture but also increases the specific surface area of BiOBr. The bandgap of the composite was narrower compared with the pure BiOBr. The CS/BiOBr composites exhibited higher photocatalytic activity than pure CS and BiOBr under visible light irradiation, and a higher first-order reaction rate constant (k) of 0.043 7 min^-1 than BiOBr (0.014 6 min^-1), and exhibited excellent stability and reusability during the cyclic run. The enhanced photocatalytic activity is attributed to the efficient separation of photoinduced electrons and holes. Superoxide radicals and holes were the major active species.