Due to its unique properties, manganese dioxide (MnO) has been widely used in various environmental applications. However, its efficiency is not ideal, which limits its further applications. Fortunately, facet engineering has become an important strategy for improving its efficiency. This review aims to summarize the recent research progress in the facet engineering of MnO. Firstly, the synthesis strategies of MnO with specific exposed facets are introduced in detail. Subsequently, the facet dependent properties of MnO crystals including surface energy, exposed atoms and electronic structure are concisely discussed. Furthermore, the applications of faceted MnO in terms of organic pollutant removal, air pollutant removal, heavy metal removal, energy production and storage are systematically reviewed. Finally, the remaining challenges are summarized and the perspectives for future research are stated. These are believed to provide guidelines for the development of facet engineering of MnO crystals.

中文翻译：

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MnO2 的面工程：提高其效率的重要策略

由于其独特的性能，二氧化锰（MnO）已广泛应用于各种环境应用中。但其效率并不理想，限制了其进一步的应用。幸运的是，分面工程已成为提高其效率的重要策略。本文旨在总结MnO晶面工程的最新研究进展。首先，详细介绍了具有特定暴露面的MnO的合成策略。随后，简要讨论了 MnO 晶体的晶面相关特性，包括表面能、暴露原子和电子结构。此外，系统综述了多面MnO在有机污染物去除、空气污染物去除、重金属去除、能源生产和储存等方面的应用。最后，总结了剩余的挑战并阐述了未来研究的前景。这些被认为为 MnO 晶体晶面工程的发展提供了指导。