To prevent metal catalysts from agglomeration and leaching, encapsulating metal nanoparticles in carbon shells has attracted much attention in electro-Fenton (EF) processes. However, most of the carbon–metal catalysts were suffering from slow regeneration of Fe²⁺ due to the unavailable redox reactions at electrode surface, which hindered the EF efficiency. Here, we report a novel boron doped graphene (BrGO) wrapped FeS₂ nanocomposite (FeS₂@BrGO), which exhibits extremely high catalytic performance due to the synthetic interaction between BrGO and FeS₂, as well as the efficient regeneration of Fe(II). The EF system with FeS₂@BrGO could completely remove 50 mg L^-1 bisphenol A within 20 min under neutral pH. EPR results suggest the existing of abundant persistent free radicals and reductive sulfur could directly donate electron to Fe(III). The electrochemical measurements further demonstrated the decreased reduction potential of Fe(III)/Fe(II) by the coordination between Fe(III) and surface oxygen-containing functional groups. Reactive organic radicals also played an important role in reducing Fe(III) to Fe(II). These findings provide a new strategy for hybrid catalysts combining graphene shells with metal sulfide, which has great potential in wastewater treatment.

为了防止金属催化剂的团聚和浸出，将金属纳米颗粒封装在碳壳中已引起电子芬顿（EF）工艺的广泛关注。但是，大多数碳金属催化剂由于电极表面无法进行的氧化还原反应而使Fe ^2+的再生缓慢，从而阻碍了EF效率。在这里，我们报道了一种新型的掺硼石墨烯（BrGO）包裹的FeS ₂纳米复合材料（FeS ₂ @BrGO），由于BrGO和FeS ₂之间的合成相互作用以及Fe（II）的高效再生，其表现出极高的催化性能。）。带有FeS ₂ @BrGO的EF系统可以完全去除50 mg L ^-1双酚A在中性pH下20分钟内。EPR结果表明存在大量持久的自由基和还原性硫可以直接将电子赠予Fe（III）。电化学测量结果进一步表明，通过Fe（III）和表面含氧官能团之间的配位，Fe（III）/ Fe（II）的还原电位降低。反应性有机基团在将Fe（III）还原为Fe（II）中也发挥了重要作用。这些发现为石墨烯壳与金属硫化物结合的杂化催化剂提供了新的策略，在废水处理中具有巨大的潜力。