Block Copolymer Self‐Assembly Guided Synthesis of Mesoporous Carbons with In‐Plane Holey Pores for Efficient Oxygen Reduction Reaction

Abstract

In this paper, a simple approach, using interfacial self‐assembly of block copolymers (BCPs) on self‐sacrificial templates, for preparing mesoporous carbons with in‐plane holey pores, including nitrogen atom‐doped carbon nanosheets and nanoflowers (denoted as NHCSs and NHCFs), is reported. The approach employs sheet‐ or flower‐like layered double hydroxide as the templates, P123 copolymer as the pore‐directing agent, and m‐phenylenediamine as the carbon source. The holey mesopores may shorten the mass transfer distance in the internal active sites of stacked nanosheets, while the 3D packing mode of nanosheets can reduce pore blockage caused by their tight stacking. Profiting from these structural advantages, acting as electrocatalysts for oxygen reduction reaction (ORR), both NHCSs and NHCFs show excellent catalytic performance better than that of carbon nanosheets without holey pores. Particularly, NHCFs exhibit a high half‐wave‐potential (0.82 V) and a limiting current density (5.4 mA cm−2), close to those of commercial Pt–C catalysts. This study provides valuable clues on building mesoporous materials with in‐plane holey pores as well as on the effect of pore structure and stacking mode of 2D materials on their electrocatalytic ORR performance.

Practical Classification of Catalysts for Oxygen Reduction Reactions: Optimization Strategies and Mechanistic Analysis

“…The electrochemical test shows that the half-wave potential Co 9 S 8 applied to ORR is 0.707 V, which is better than most nonnoble metal ORR catalysts and the most advanced Pt/C catalysts. Jiang et al [46] used a simple strategy of interfacial self-assembly of block copolymers (BCPs) on self-sacrificial templates, and used flaky or flower-like layered double hydroxides as templates to prepare N-atom-doped carbon nanoplates and nanoflowers (denoted as NHCSs and NHCFs) (Figure 1c,d). The porous mesoporous structure can shorten the mass transfer distance of the active site inside the stacked nanosheet, while the nanosheet is 3D Stacking mode reduces hole clogging caused by its tight stacking.…”

“…Reproduced with permission. [ 46 ] Copyright 2022, Wiley‐VCH; e) SEM image of ZIF@HMCS‐25%, f) TEM image of ZIF@HMCS‐25%. Reproduced with permission.…”

“…Copyright 2019, Wiley-VCH; SEM images of c) 2D sheet-like NHCSs, d) 3D flower-like NHCFs. Reproduced with permission [46]. Copyright 2022, Wiley-VCH; e) SEM image of ZIF@HMCS-25%, f) TEM image of ZIF@HMCS-25%.…”

Two-dimensional sandwich-like MXene–conductive polymer nanocomposite with in-plane cylindrical mesopores for long cycling lithium-sulfur batteries

“…However, the in-situ polymerization of the functional monomers adsorbed on the surface of MXene to construct sandwich-like heterostructures leads to the formation of dense coating organic layers on MXene surface, which causes limited exposure of active sites and impedes the improvement of sulfur loading [57]. To tackle these issues, the introduction of in-plane mesopores within the organic layers on the 2D sandwich-like heterostructures can provide a large internal active surface area to host sulfur and offer abundant electro/ion channels for electrochemical reactions [58][59][60][61][62][63]. Therefore, the active site utilization of the 2D sandwich-like heterostructures and the electrochemical performance of the resultant Li-S batteries can be improved by employing this promising strategy.…”

One‐Dimensional Helical Nanostructures from the Hierarchical Self‐Assembly of an Achiral “Rod−Coil” Alternating Copolymer

“…[19][20][21]25] In spite of these merits, the selfassembly behavior of ACPs has remained much less explored compared with that of polymers with other topologies such as block copolymers. [26][27][28][29][30][31][32][33][34] In particular, helical nanostructures formed by the self-assembly of ACPs have so far been very rarely documented. To our knowledge, there was only one successful case.…”