Electrochemical co-reduction of nitrate(NO_(3)^(-))and carbon dioxide(CO_(2))has been widely regarded as a promising route to produce urea under ambient conditions,however the yield rate of urea has remained limited.H...Electrochemical co-reduction of nitrate(NO_(3)^(-))and carbon dioxide(CO_(2))has been widely regarded as a promising route to produce urea under ambient conditions,however the yield rate of urea has remained limited.Here,we report an atomically ordered intermetallic pallium-zinc(PdZn)electrocatalyst comprising a high density of PdZn pairs for boosting urea electrosynthesis.It is found that Pd and Zn are responsible for the adsorption and activation of NO_(3)^(-)and CO_(2),respectively,and thus the co-adsorption and co-activation NO_(3)^(-)and CO_(2) are achieved in ordered PdZn pairs.More importantly,the ordered and well-defined PdZn pairs provide a dual-site geometric structure conducive to the key C-N coupling with a low kinetical barrier,as demonstrated on both operando measurements and theoretical calculations.Consequently,the PdZn electrocatalyst displays excellent performance for the co-reduction to generate urea with a maximum urea Faradaic efficiency of 62.78%and a urea yield rate of 1274.42μg mg^(-1) h^(-1),and the latter is 1.5-fold larger than disordered pairs in PdZn alloys.This work paves new pathways to boost urea electrosynthesis via constructing ordered dual-metal pairs.展开更多
基金supported by the National Natural Science Foundation of China(22379100,U21A20312)the Shenzhen Science and Technology Program(Grant No.20231121200418001)+1 种基金the Guangdong Basic and Applied Basic Research Foundation(2022B1515120084)the Key Project of Department of Education of Guangdong Province(2023ZDZX3020)。
文摘Electrochemical co-reduction of nitrate(NO_(3)^(-))and carbon dioxide(CO_(2))has been widely regarded as a promising route to produce urea under ambient conditions,however the yield rate of urea has remained limited.Here,we report an atomically ordered intermetallic pallium-zinc(PdZn)electrocatalyst comprising a high density of PdZn pairs for boosting urea electrosynthesis.It is found that Pd and Zn are responsible for the adsorption and activation of NO_(3)^(-)and CO_(2),respectively,and thus the co-adsorption and co-activation NO_(3)^(-)and CO_(2) are achieved in ordered PdZn pairs.More importantly,the ordered and well-defined PdZn pairs provide a dual-site geometric structure conducive to the key C-N coupling with a low kinetical barrier,as demonstrated on both operando measurements and theoretical calculations.Consequently,the PdZn electrocatalyst displays excellent performance for the co-reduction to generate urea with a maximum urea Faradaic efficiency of 62.78%and a urea yield rate of 1274.42μg mg^(-1) h^(-1),and the latter is 1.5-fold larger than disordered pairs in PdZn alloys.This work paves new pathways to boost urea electrosynthesis via constructing ordered dual-metal pairs.
基金supported by Shenzhen Science and Technology Program (JCYJ20200109105803806, SGDX20201103095802006, RCYX20200714114535052,JCYJ20190808150001775,and CYJ20190808143007479)the National Natural Science Foundation of China (U21A20312 and 21975162)Guangdong Basic and Applied Basic Research Foundation (2022B1515120084)。
文摘合理设计铂纳米颗粒尺寸是制备高效氧还原电催化剂的关键.本工作中,我们借助静电纺丝和ZIF-8的双重限域作用合成了超细铂纳米颗粒锚定在多孔碳纳米纤维上的催化材料.低Pt负载(4.2 wt%)的Pt@PCNFs在碱性和酸性电解质中均表现出优异的氧还原反应活性,其质量活性分别为41和51 A gPt^(-1),分别是商业Pt/C催化剂相应值的8倍和10倍.在不同温度的碱性和酸性环境的计时安培试验和加速稳定性实验中, Pt@PCNFs的稳定性均优于Pt/C基准.该催化剂的优异性能可归因于小尺寸的Pt纳米颗粒、丰富多孔的纤维结构、Pt纳米颗粒与N掺杂碳纳米纤维之间的强金属载体相互作用以及碳壳层的保护作用.
