Design of a Three-Dimensional Interconnected Hierarchical Micro-Mesoporous Structure of Graphene as Support Material for Spinel NiCo2O4 Electrocatalysts toward Oxygen Reduction Reaction
Design of a Three-Dimensional Interconnected Hierarchical Micro-Mesoporous Structure of Graphene as Support Material for Spinel NiCo2O4 Electrocatalysts toward Oxygen Reduction Reaction
复制标题
石墨烯三维互连多级微介孔结构作为尖晶石NiCo2O4电催化剂氧还原反应载体材料的设计
DOI：
10.1021/acs.jpcc.8b08692
复制
发表时间：
2018
影响因子：
3.7
通讯作者：
Wang Suwen
中科院分区：
文献类型：
--
作者：
Zhang Tingwei;Li Zhongfang;Zhang Zhixu;Wang Likai;Sun Peng;Wang Suwen
开发具有成本效益的高性能氧还原反应电催化剂是燃料电池和金属空气电池的主要问题。在此，首先通过模板法制备了一种新型互连分层三维石墨烯（3D-HG），其中煤焦油沥青和CaCO3分别用作碳前驱体和模板。 CaCO3在800℃下热解可产生CaO和CO2，所获得的CaO可以作为模板，CO2可以促进微孔的形成，从而促进3D-HG中介孔的互连。采用水热法在3D-HG上合成尖晶石NiCo2O4，记为NiCo2O4/3D-HG。所制备的NiCo2O4/3D-HG催化剂保留了石墨烯的分级微介孔结构。受益于分级结构的质量传输便利性，NiCo2O4/3D-HG表现出比NiCo2O4/还原氧化石墨烯（0.79V）、NiCo2O4/碳纳米管（0.73V）和20wt%Pt/C（0.81V）更好的高性能半波电位（0.82V vs 可逆氢电极（RHE）），并且表现出比20%更高的耐久性。重量％Pt/C。这项工作证明NiCo2O4/3D-HG是一种经济高效的燃料电池或金属空气电池电催化剂。
The development of cost-effective electrocatalysts with high performance for oxygen reduction reaction is the main problem for fuel cells and metal-air batteries. Herein, a novel interconnected hierarchical three-dimensional graphene (3D-HG) is first fabricated by the templated method, where coal tar pitch and CaCO3 were used as carbon precursor and template, respectively. The pyrolysis of CaCO3 could produce CaO and CO2 at 800 degrees C, where the obtained CaO can serve as the template and CO2 can promote the formation of micropores to facilitate the interconnect of the mesopores in 3D-HG. Spinel NiCo2O4 is synthesized on 3D-HG by the hydrothermal method, which is denoted as NiCo2O4/3D-HG. The as-prepared NiCo2O4/3D-HG catalysts retain the hierarchical micro-mesoporous structure of graphene. Benefiting from the mass transport convenience of the hierarchical structure, NiCo2O4/3D-HG exhibits high-performance half-wave potential (0.82 V vs reversible hydrogen electrode (RHE)) better than NiCo2O4/reduced graphene oxide (0.79 V), NiCo2O4/carbon nanotubes (0.73 V), and 20 wt % Pt/C (0.81 V), and shows higher durability than 20 wt % Pt/C. This work proves that NiCo2O4/3D-HG is a cost-effective electrocatalyst for fuel cells or metal-air batteries.