Bio‐Inspired Synthesis of an Ordered N/P Dual‐Doped Porous Carbon and Application as an Anode for Sodium‐Ion Batteries

Abstract

Carbonaceous materials are one of the most promising anode materials for sodium-ion batteries, because of their abundance, stability, and safe usage. However, the practical application of carbon materials is hindered by poor specific capacity and low initial Coulombic efficiency. The design of porous structure and doping with heteroatoms are two simple and effective methods to promote the sodium storage performance. Herein, the N, P co-doped porous carbon materials are fabricated using renewable and biodegradable gelatin as carbon and nitrogen resource, phosphoric acid as phosphorus precursor and polystyrene nanospheres as a template. The product can deliver a reversible capacity of 230 mA h g at a current density of 0.2 A g , and even a high capacity of 113 mA h g at 10 Ag . The enhanced sodium storage performance is attributed to the synergistic effect of the porosity and the dual-doping of nitrogen and phosphorus.

Synthesis Strategies and Structural Design of Porous Carbon‐Incorporated Anodes for Sodium‐Ion Batteries

“…Besides, gelatin, a biopolymer produced by acid or alkali denaturation of collagen, is considered as a promising carbon and nitrogen precursor due to its rich heteroatom elements (e.g., N and P), which would be effective for enhancing the electronic conductivity of carbon anode material and provide more active sites for carbon and Na ion interaction. A bio‐inspired N, P codoped, ordered and porous carbon material was reported by Yang's group using cheap and biodegradable gelatin as their carbon and nitrogen source, assisted by phosphoric acid and polystyrene nanospheres as phosphorus precursor and template, respectively (Figure j–m) . The sodium storage performance was evaluated and found to feature good cycling stability (230 mAh g −1 at 0.2 A g −1 after 700 cycles) and excellent rate capability (113 mAh g −1 at 10 A g −1 ), which could be attributed to the synergistic effects of the ordered porous 3D structure and dual‐doping of N and P.…”

“…j,k) SEM images, and l,m) TEM images of NP‐OPC material. Reproduced with permission . Copyright 2017, Wiley‐VCH.…”

A Heterostructure Coupling of Bioinspired, Adhesive Polydopamine, and Porous Prussian Blue Nanocubics as Cathode for High‐Performance Sodium‐Ion Battery

“…[ 4–8 ] Among these, the sodium‐ion batteries (SIBs) have received growing research attention, on account of the inexhaustible and low‐cost nature of sodium resource, as well as its suitable redox potential and safety. [ 9–12 ]…”

Highly crystalline nickel hexacyanoferrate as a long-life cathode material for sodium-ion batteries

“…However, a signicant distortion of and strain on the crystal lattice may be induced due to the broad radius of Na + during the incorporation phase, and this also poses challenges in nding relevant electrode materials for SIBs. [18][19][20][21] Some cathodes, P 2 -Na 0.6 7Co 1Àx Ti x O 2 , 22 Na 3 V 2 (PO 4 ) 3 , 23,24 NaTi 2 (PO 4 ) 3 , 25,26 and Na 0.7 [Mn 1Àx Li x ]O 2+y , 27 demonstrated signicant performance in terms of variable capacity, including rate efficiency, but due to certain phase transitions, and large changes in volume during cycling, they have failed to meet long cycling-life requirements. Prussian blue analogs (PBAs), a kind of metal-organic framework with the formula A x M y [M 0 (CN) 6 ] z $nH 2 O, where A refers to an alkaline metal and M, M 0 refer to transition metals, have been widely studied as attractive cathodes for SIBs in the past decade due to their high theoretical capacity and long-cycle life.…”