中文摘要：

通过电子探针（EMPA）、X射线光电子能谱（Ⅺ]S）、漫反射谱（DlRs）、光致发光谱（PL）、透射电镜（TEM）、扫描电镜（sEM）和霍尔效应（Hall—effect）等测试手段对天然闪锌矿样品的半导体物理化学性能进行了表征分析。分析结果认为，天然闪锌矿良好的可见光响应性能主要源自其晶格内丰富的类质同像替代离子。此外，样品中的变价元素Fe能够参与价带光生空穴的捕获，提高导带光生电子的利用率，从而提高其光催化活性。样品中丰富的缺陷也有利于光催化活性的提高，大量的解理面和裂开面能够提供较完整的晶面增加反应活性点位，空位缺陷和晶格膨胀畸变等可以提高光生电子空穴对的分离效率。与其特殊的物理化学性质相符，天然闪锌矿光催化还原降解甲基橙的实验证明了其较高的可见光催化还原活性。本研究结果也预示着天然半导体矿物闪锌矿作为一种新的低成本、高效率的可见光催化材料将在环境污染治理领域具有一定的应用前景。

英文摘要：

Natural sphalerite as a novel cost-effective photocatalyst was characterized by means of electron microprobe analysis （EM- PA）, X-ray photoelectron spectroscopy （XPS）, diffuse reflectance spectroscopy （DRS）, photoluminescence （PL）, transmission elec- tron microscope （TEM）, scanning electron microscope （SEM） and Hall-effect measurements. The results show that the visible light response of the natural sphalerite sample results from the presence of substituting metal ions. Besides, the variable-valence element of Fe can act as a hole scavenger in the process of Fe2＋ ＋ h＋--＊ Fe3＋ , thus improving the efficiency of conduction band electrons and strengthening the photoactivity. Cleavage planes and fracture surfaces can improve the photocatalytic activity by providing more active sites than perfect faces. Other defects like charge vacancies and lattice expansion with their possible roles of improving the efficiency of electron-hole pair separation are analyzed. The photoreductive reactions prove that the natural sphalerite sample exhibits a high pho- toactivity on reducing methyl orange under visible light irradiation, which is consistent with its specific characterization. The results also demonstrate that natural sphalerite as a new cost-effective photocatalyst driven by visible light will have certain application prospects in environmental remediation.