析氧反应(OER)作为一种主要的阳极反应,在许多电化学能量转换过程中起到了重要的作用.尽管铱(Ir)基材料是目前最先进的OER催化剂,其稀缺性很大程度上限制了该类材料的实际应用.在此,我们利用简便的硼酸辅助法成功制备了硼掺杂的无定形...析氧反应(OER)作为一种主要的阳极反应,在许多电化学能量转换过程中起到了重要的作用.尽管铱(Ir)基材料是目前最先进的OER催化剂,其稀缺性很大程度上限制了该类材料的实际应用.在此,我们利用简便的硼酸辅助法成功制备了硼掺杂的无定形氧化铱(IrO_(x)-B).该催化剂在300 mV过电位处展现出2779 A g^(-1)的超高OER质量活性,是已报道的最佳酸性OER催化剂之一.我们发现硼酸不仅可以促进Ir位点的暴露,还能够以偏硼酸根的形式掺杂进入无定形Ir O_(x)中,并进一步优化Ir的电子与配位结构,进而实现本征活性的提升.有趣的是,这种方法具有一定的普适性,能够提升其他金属氧化物催化剂的OER催化活性.这为制备高质量活性的OER电催化剂提供了一种通用的策略.展开更多
The sluggish reaction kinetics of oxygen evolution reaction(OER)has largely lowered the efficiency of electrochemical water splitting.Ir represents one of the state-of-the-art electrocatalysts for promoting OER especi...The sluggish reaction kinetics of oxygen evolution reaction(OER)has largely lowered the efficiency of electrochemical water splitting.Ir represents one of the state-of-the-art electrocatalysts for promoting OER especially in acidic electrolytes.However,it remains a formidable challenge to synthesize high-quality one-dimensional(1D)Ir-based nanostructures for improved electrocatalytic performance.Herein,a template-assisted synthesis method is reported wherein 1D porous Ir-Te nanowires(Ir-Te NWs)are synthesized with Te NWs serving as the template.The Ir-Te NWs exhibit highly enhanced OER performance compared to commercial IrO_(2) and Ir/C.In detail,the overpotentials to reach 10 mA cm^(-2) are 248 and 284 mV in 1 M KOH and 0.5 M H2S04,respectively,much lower than those of commercial catalysts.The Ir-Te NWs also show smaller Tafel slopes than commercial IrO_(2) and Ir/C,signifying faster reaction kinetics.Besides,much more durable OER activity can be maintained for Ir-Te NWs with negligible decay during 25 and 20 h stability tests in 1 M KOH and 0.5 M H_(2)SO_(4),respectively.Further analysis indicates that the significantly improved OER performance of Ir-Te NWs could be ascribed to the larger electrochemical surface area and smaller electrical resistance.More significantly,the templated synthesis of Ir-Te NWs can be facilely extended to the fabrication of other metal-Te NWs including Ru-Te,Rh-Te and Pt-Te NWs.The design and synthesis of 1D metal-based NWs in this work provide important inspiration for the synthesis of diversified 1D metallic nanostructures with distinctly enhanced catalytic performance and beyond.展开更多
基金financially supported by the Ministry of Science and Technology (2017YFA0208200 and 2016YFA0204100)the National Natural Science Foundation of China (22025108 and 51802206)+3 种基金the Natural Science Foundation of Jiangsu Province (BK20180846)the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)the Project of Scientific and Technologic Infrastructure of Suzhou (SZS201905)the Start-up Supports from Xiamen University。
文摘析氧反应(OER)作为一种主要的阳极反应,在许多电化学能量转换过程中起到了重要的作用.尽管铱(Ir)基材料是目前最先进的OER催化剂,其稀缺性很大程度上限制了该类材料的实际应用.在此,我们利用简便的硼酸辅助法成功制备了硼掺杂的无定形氧化铱(IrO_(x)-B).该催化剂在300 mV过电位处展现出2779 A g^(-1)的超高OER质量活性,是已报道的最佳酸性OER催化剂之一.我们发现硼酸不仅可以促进Ir位点的暴露,还能够以偏硼酸根的形式掺杂进入无定形Ir O_(x)中,并进一步优化Ir的电子与配位结构,进而实现本征活性的提升.有趣的是,这种方法具有一定的普适性,能够提升其他金属氧化物催化剂的OER催化活性.这为制备高质量活性的OER电催化剂提供了一种通用的策略.
基金supported by the National Key R&D Program of China(Nos.2017YFA0208200 and 2016YFA0204100)the National Natural Science Foundation of China(No.22025108)。
文摘The sluggish reaction kinetics of oxygen evolution reaction(OER)has largely lowered the efficiency of electrochemical water splitting.Ir represents one of the state-of-the-art electrocatalysts for promoting OER especially in acidic electrolytes.However,it remains a formidable challenge to synthesize high-quality one-dimensional(1D)Ir-based nanostructures for improved electrocatalytic performance.Herein,a template-assisted synthesis method is reported wherein 1D porous Ir-Te nanowires(Ir-Te NWs)are synthesized with Te NWs serving as the template.The Ir-Te NWs exhibit highly enhanced OER performance compared to commercial IrO_(2) and Ir/C.In detail,the overpotentials to reach 10 mA cm^(-2) are 248 and 284 mV in 1 M KOH and 0.5 M H2S04,respectively,much lower than those of commercial catalysts.The Ir-Te NWs also show smaller Tafel slopes than commercial IrO_(2) and Ir/C,signifying faster reaction kinetics.Besides,much more durable OER activity can be maintained for Ir-Te NWs with negligible decay during 25 and 20 h stability tests in 1 M KOH and 0.5 M H_(2)SO_(4),respectively.Further analysis indicates that the significantly improved OER performance of Ir-Te NWs could be ascribed to the larger electrochemical surface area and smaller electrical resistance.More significantly,the templated synthesis of Ir-Te NWs can be facilely extended to the fabrication of other metal-Te NWs including Ru-Te,Rh-Te and Pt-Te NWs.The design and synthesis of 1D metal-based NWs in this work provide important inspiration for the synthesis of diversified 1D metallic nanostructures with distinctly enhanced catalytic performance and beyond.
