Abatement of elemental mercury (Hg⁰) pollution in coal combustion flue gas remains a challenging task especially for the optimal trade-off among effectiveness, environmental-friendliness and cost. In this work, magnetite (Fe₃O₄) was simply selenized (Fe₃O_4-xSe_y) as an efficient and recyclable sorbent for Hg⁰ sequestration from coal combustion flue gas. The Fe₃O_4-xSe_y as obtained exhibited an advantageous core-shell like spherical structure, in which the interior Fe₃O₄ core kept unchanged during the selenization process and warranted the recyclability of Fe₃O_4-xSe_y, while the exterior part exposed to Hg⁰ was selenized into iron diselenide (FeSe₂) that has high affinity towards Hg⁰. Moreover, the selenization process introduced more mesopores that were favorable for Hg⁰ migration and accommodation. Co-benefitted from these perspectives, the Fe₃O_4-xSe_y exhibited a Hg⁰ adsorption capacity and uptake rate as high as 8.8 mg g^-1 and 3.7 μg g^-1 min^-1, respectively, far exceeding the capacity and rate of bare Fe₃O₄ and traditional Hg⁰ remediators. The Hg⁰ stably immobilized by Fe₃O_4-xSe_y primarily as mercury selenide (HgSe) indicates the Hg-laden Fe₃O_4-xSe_y has negligible mercury re-emission concerns when it is dumped and landfilled. The spent Fe₃O_4-xSe_y can also be effectively retrieved and regenerated for reusing purpose with mercury recovery simultaneously, which could dramatically save the operation costs. Thus, the Fe₃O_4-xSe_y can be expected to be a promising alternative to traditional sorbents for Hg⁰ sequestration from coal combustion flue gas considering its high efficiency, negligible environmental risk and decent recyclability and reusability.

减少燃煤烟气中的汞（Hg ⁰）污染仍然是一项艰巨的任务，尤其是要在有效性，环境友好性和成本之间实现最佳平衡。在这项工作中，磁铁矿（Fe ₃ O ₄）被简单地硒化（Fe ₃ O _4-x Se _y），作为从煤燃烧烟气中吸收Hg ⁰的有效且可回收的吸附剂。中的Fe ₃ ö _4-x硒_ý作为获得表现出有利的核-壳状的球形结构，其中，所述内部的Fe ₃ ö ₄在硒化过程中，铁芯保持不变，并保证了Fe ₃ O _4-x Se _y的可回收性，而暴露于Hg ⁰的外部部分则被硒化为对Hg ⁰具有高亲和力的二硒化铁（FeSe ₂）。此外，硒化过程引入了更多的中孔，这些孔有利于Hg ^0的迁移和调节。从这些角度共同受益，Fe ₃ O _4-x Se _y表现出Hg ⁰吸附能力，吸收率高达8.8 mg g ^-1和3.7μgg ^-1 min ^-1分别远远超过了裸Fe ₃ O ₄和传统Hg ⁰修复剂的容量和速率。汞⁰稳定地固定化的Fe ₃ ö _4-x硒_ý主要作为硒化汞（HgSe）表示汞载货的Fe ₃ ö _4-x硒_ý具有可忽略的汞再排放的关注时，它被倾倒和填埋。用过的Fe ₃ O _4-x Se _y也可以被有效地回收和再生，以实现再利用，同时回收汞，可以大大节省运营成本。因此，Fe ₃ O_考虑到4-x Se _y高效，可忽略的环境风险以及良好的可回收性和可再利用性，它有望成为从煤烟气中分离Hg ^0的传统吸附剂的有前途的替代品。