The oxygen reduction reaction (ORR

The oxygen reduction reaction (ORR ) is an important process in energy conversion and storage
devices such as fuel cells and metal-air batteries[1-2]. Pt and its alloys are well known as most
efficient catalysts for ORR[3-4], but their sluggish kinetics in ORR, high price, limit supply, and poor
durability impede the development and commercialization of these devices. Nowadays, tremendous
effort has been geared towards developing non-platinum-group-metal (non-PGM) catalysts for ORR 5
in view of low cost and better durability and tolerance to fuel crossover. In general, there are three
types of non-PGM materials. First one is macrocyclic metal-N4 complexes, containing single
macrocycle[5], cofacial macrocycle-based dimmers[6], and their derivatives[7]. Second one is carbon
materials doped with heteroatoms (such as N[8-9], P[10], S[11], Se[12], B[13], and F[14]) , including
dual-doped[15] and trinary-doped[16] carbon materials. The last is the materials based on transition 10
metals, such as transition metal chalcogenide[17], transition metal nitride[18-19], and transition metal or
metal oxide supported on nitrogen-doped carbon materials[20-21].
No matter what type of catalyst will be used, to be viable, its activity should at least approach
that of traditional but more expensive Pt/C catalysts. Among various materials, N-doped carbon
materials, including N-doped graphene (usually referred to as reduced graphene oxide, N-rGO), 15
N-doped carbon nanotubes (N-CNT) and their composites (N-rGO-CNT), have attracted much
attention[8,22-23]. In linear sweep voltammetry (LSV) measurements, N-rGO often exhibited more
positive on-set potential (close to that of Pt/C catalysts) owing to more catalytically active sites, but
inferior half-wave potential and current density caused by the insufficient conductivity and mass
transfer due to incomplete reduction and stacking of graphene sheets. N-CNT commonly showed 20
insufficient electrocatalytic activity for ORR but held the merits of good conductivity and mass
transfer. Taking in account these facts, N-rGO-CNT prepared via several methods were reported and
exhibited reasonable catalytic activity and durability for ORR[12-23-24], although their activities still
need to be much improved. On the other hand, N-doped porous carbon materials allowed more active
sites to engage in ORR due to large surface area, and thus demonstrated enhanced ORR catalytic 25
activity[25]. However, the activities of these porous catalysts still much lower than that of Pt-based
catalysts despite tremendous efforts have been made. The main reason could be attributed to poor
electron conductivity caused by heavy heteroatom doping and porous structures.
In consideration of these situations, we reported here a porous nitrogen-doped graphene/carbon
nanotubes composite with enhanced electrocatalytic performance for ORR by boosting the activity of 30

結果 (中文) 3:

氧还原反应（ORR）是一个重要的过程，在能源转换和存储
设备如燃料电池和金属-空气电池[ 1-2 ]。铂及其合金是众所周知的最
高效催化剂ORR [3-4]，但他们的呆滞动力学奥尔，价格高，限制供应，
耐久性差阻碍了这些设备的发展和商业化。如今，巨大的
的努力已朝向非铂族金属（非PGM）为
5或在低成本和更好的耐久性和耐燃料交叉视图催化剂。一般来说，有三种非金属材料
。第一个是大环metal-n4配合物，含单
大环[ 5 ]，[ 6 ] cofacial大环为基础的调光器，和它们的衍生物[ 7 ]。第二个是碳
杂原子掺杂材料（如N [ 8 ]，P [ 10 ]的[ 11 ]，[ 12 ]，硒，B和F [ 13 ]，[ 14 ]），包括
双掺杂[ 15 ]和[ 16 ]三元掺杂碳材料。最后是基于10
过渡金属材料，如过渡金属硫属化合物[ 17 ]，过渡金属氮化物[日]，和过渡金属或金属氧化物负载的
氮掺杂的碳材料[ 21 ]。
无论是什么类型的催化剂将被使用，是可行的，其活性至少应
传统方法，但更昂贵的Pt／C催化剂。在各种材料中，氮掺杂碳
材料，包括N-掺杂的石墨烯（通常称为还原氧化石墨烯，n-rgo），15
氮掺杂碳纳米管（n-cnt）及其复合材料（n-rgo-cnt），吸引了很多的关注[ 8
，22 ]。线性扫描伏安法（LSV）测量，n-rgo往往表现出积极的集势更
（接近的Pt／C催化剂）由于更多的催化活性位点，但
下半波电位和电流不足的电导率和由于不完全还原的石墨烯片层的质量和
转移引起的密度。n-cnt通常显示20
没有足够的氧还原催化活性而举行的良好的导电性和质量
转移的优点。考虑到这些事实，通过几种方法的报道和
表现出催化活性和耐久性的合理12-23-24 ]或者[准备n-rgo-cnt，虽然他们的活动仍然
需要很大的改进。在另一方面，氮掺杂多孔炭材料允许更积极的
网站从事或者由于大的表面面积，从而表现出增强的氧还原的催化活性的25
[ 25 ]。然而，这些多孔催化剂的活性仍然远低于铂基催化剂
尽管已作出了巨大的努力。主要的原因可以归因于穷人
电子导电性造成的重杂原子掺杂的多孔结构。
在这些情况考虑，本文报道一多孔氮掺杂石墨/碳纳米管增强
电催化性能提高30
ORR活性复合材料