Bioinspired Synthesis of Melaninlike Nanoparticles for Highly N-Doped Carbons Utilized as Enhanced CO₂ Adsorbents and Efficient Oxygen Reduction Catalysts

Abstract

Highly N-doped nanoporous carbons have been of great interest as a high uptake CO2 adsorbent and as an efficient metal-free oxygen reduction reaction (ORR) catalyst. Therefore, it is essential to produce porosity-tunable and highly N-doped carbons through cost-effective means. Herein, we introduce the bioinspired synthesis of a monodisperse and N-enriched melaninlike polymer (MP) resembling the sepia biopolymer (SP) from oceanic cuttlefish. These polymers were subsequently utilized for highly N-doped synthetic carbon (MC) and biomass carbon (SC) spheres. An adequate CO2 activation process fine-tunes the ultramicroporosity (<1 nm) of N-doped MC and SC spheres, those with maximum ultramicroporosities of which show remarkable CO2 adsorption capacities. In addition, N-doped MC and SC with ultrahigh surface areas of 2677 and 2506 m2/g, respectively, showed excellent ORR activities with a favored four electron reduction pathway, long-term durability, and better methanol tolerance, comparable to a commercial Pt-based catalyst.

Natural eumelanin-based porous N-doped carbon as an active bio-catalyst for base- and initiator-free aerobic oxidation of olefins and alkyl aromatic hydrocarbons

“…[19][20][21] The N-doped carbon synthesized from synthetic melanin has been reported to be an outstanding material for the adsorption of O 2 . 22 Recently, porous carbon has been prepared using allomelanin, which was synthesized from 1,8-dihydroxynaphthalene and is utilized for gas-and toxin-adsorption studies. 23 Furthermore, graphitic carbon nanotubes have been shown to perform a reduction of nitroarenes with doped synthetic melanin.…”

Micro Flower-Like Hierarchical Mo2C/Co@NC (N-Doped Carbon) for Efficient Bifunctional Electrocatalyst

“…401 eV), and N oxide (ca. 405 eV) were deconvoluted [38][39][40]. Interestingly, pyridinic-N, pyridinic-N, and graphite-N can provide more active sites, higher electron conduction, and greater stability during electrochemical processes [13,26,31], as mentioned earlier.…”

Progress in polydopamine-based melanin mimetic materials for structural color generation

“…From this viewpoint, research focusing on the structure-function relationship between natural melanin and PDA is progressing [ 49 ]. Inspired by the functionality of natural melanin, PDA-based functional materials such as free radical scavengers [ 50 ], UV absorbers [ 51 ], metal ion probes [ 52 ], catalyst [ 53 , 54 ], and antioxidants [ 55 ] have been developed.…”