Nitrate is the leading cause of eutrophication worldwide and is one of the most challenging pollutants for restoration of polluted surface waters such as lakes, rivers and reservoirs. We report herein a new architecture of iron nanoparticles for high-efficiency denitrification by selective reduction of nitrate (NO₃⁻) to dinitrogen (N₂). The iron nanoparticles are doped with nitrogen (FeN) and encapsulated within a thin layer of nitride-carbon (NC). The nanoparticles have high pyrrolic N content (17.4 at.%) and large specific surface area (2040 m²/g). Laboratory experiments demonstrated high N₂ selectivity (91%) and nitrate removal capacity (6004 mg N/g Fe) for treatment of nitrate-containing water. This iron-based nanomaterial overcomes shortcomings of conventional catalysts by eliminating the use of precious and toxic heavy metals (e.g., Pd, Pt, Cu, Ni) and minimizing the generation of undesirable byproducts (e.g., ammonia) from the reactions with nanoscale zero-valent iron (nZVI). The multiple electron transfers process from NO₃⁻ to N₂ can be fine-tuned by adjusting the NC shell thickness. Superior electrocatalytic performance, low cost and minimal environmental impact of the iron-derived nanocatalyst offer promising prospects for water purification, waste treatment and environmental remediation.

硝酸盐是全球富营养化的主要原因，并且是恢复受污染的地表水（如湖泊，河流和水库）的最具挑战性的污染物之一。（NO我们通过硝酸盐的选择性还原在此报告的铁纳米颗粒的高效率脱氮的新架构₃ ^- ），以二氮（N ₂）。铁纳米粒子掺杂有氮（FeN），并封装在氮化碳（NC）的薄层内。纳米颗粒具有高的吡咯N含量（17.4原子％）和大的比表面积（2040m ² / g）。实验室实验证明N ₂高选择性（91％）和硝酸盐去除能力（6004 mg N / g Fe）用于处理含硝酸盐的水。这种铁基纳米材料通过消除对贵重和有毒重金属（例如Pd，Pt，Cu，Ni）的使用，克服了传统催化剂的缺点，并最大程度地减少了与零级纳米级反应产生的不良副产物（例如氨）的产生。价铁（nZVI）。多电子转移处理从NO ₃ ^-到N ₂可以被微调通过调整NC壳厚度。源自铁的纳米催化剂优异的电催化性能，低成本和对环境的最小影响为水净化，废物处理和环境修复提供了有希望的前景。