Electrochemical CO₂ reduction reaction (ECO₂RR) is a potentially promising way of producing sustainable energy by converting CO₂ into fuels or useful chemicals using alternative power sources such as solar and wind. However, finding cheap and abundant materials with a high catalytic activity for CO₂ reduction is critical for future larger-scale applications of ECO₂RR. Herein, we used petroleum coke (PC), an industrial waste, as the carbon source for preparing highly efficient ECO₂RR catalysts. By doping nickel and nitrogen into oxidized PC (Ni–N-PC), an ∼97% Faradaic efficiency of CO production has been achieved with a current density of ∼18 mA/cm² at −0.8 V versus the reversible hydrogen electrode. By further doping iron into the Ni–N-PC catalyst (forming Fe/Ni–N-PC), a 90% Faradaic efficiency of CO and a 20 mA/cm² CO partial current density were achieved. The ECO₂RR performance of the above PC-based catalysts was comparable to that of traditional graphite-based catalysts, but the former is an industrial waste and costs little. Findings from this work provide insight into transfer of industrial waste into a carbon precursor under similar treatment to synthesize efficient ECO₂RR catalysts.

中文翻译：

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源自工业废石油焦的高效镍，铁和氮共掺杂碳催化剂，用于电化学还原CO ₂

电化学CO ₂还原反应（ECO ₂ RR）是一种潜在有希望的方法，可通过使用替代能源（例如太阳能和风能）将CO ₂转化为燃料或有用的化学物质来产生可持续的能源。但是，对于ECO ₂ RR的未来大规模应用而言，找到便宜且丰富的具有高催化活性的材料来降低CO ₂至关重要。在此，我们使用工业废料石油焦（PC）作为制备高效ECO ₂ RR催化剂的碳源。通过将镍和氮掺杂到氧化的PC（Ni–N-PC）中，在电流密度约为18 mA / cm ^{2的情况下}，CO产生的法拉第效率达到了97％相对于可逆氢电极的电压为-0.8V。通过将铁进一步掺杂到Ni-N-PC催化剂中（形成Fe / Ni-N-PC），可实现90％的CO法拉第效率和20 mA / cm ^2的CO分流密度。上述基于PC的催化剂的ECO ₂ RR性能可与传统的基于石墨的催化剂相媲美，但是前者是工业废料并且成本低廉。这项工作的发现为深入了解工业废物在相似处理下向碳前体的转移提供了有效的ECO ₂ RR催化剂。