Stereodefined Codoping of sp-N and S Atoms in Few-Layer Graphdiyne for Oxygen Evolution Reaction

Abstract

Developing metal-free catalysts with high catalytic activity for oxygen evolution reaction (OER) is essentially important for energy and environment-related techniques. Compared with individual element doping, doping carbon materials with multiple heteroelements has more advantages for enhancing the OER performance. However, doped sites for the different atoms are highly uncontrollable under the reported methods, which hinder the deeper understanding on the relationship between structure and property, and also limit the enhancement of catalytic activity. Our latest research has reported a method to site-controlled introducing a new form of nitrogen atoms, i.e. sp-hybridized nitrogen (sp-N), into graphdiyne, showing its potential advantages in OER catalysis. Since the sites of sp-N atoms are defined in graphdiyne, and the doping sites for S atoms are well understood, the relative position between N and S can be further defined. It gives us a chance to understand deeply the mechanism in the N, S heteroelements doped metal-free catalyst. Experimental results present that the codoping of sp-N and S atoms brought an excellent OER performance with low overpotential and high current density owning to the effectively synergistic effect of the stereodefined heteroatoms.

Boosting ORR/OER Activity of Graphdiyne by Simple Heteroatom Doping

“…Yang et al heated the graphdiyne with benzyl disulfides, and the as‐prepared S‐doped graphdiyne behaves better than the pristine graphdiyne as the electrode for Li‐ion battery . Zhao et al synthesized N, S codoped graphdiyne (NSFLGDY) by calcining few‐layer graphdiyne oxides with melamine and dibenzyl sulfide and confirmed the superior OER activity of NSFLGDY, which is even better than RuO 2 …”

Nanostructured Carbon Based Heterogeneous Electrocatalysts for Oxygen Evolution Reaction in Alkaline Media

“…According to the research work, N doping types are diverse, while S atoms preferred to replace the carbon atoms at benzene rings . Thus, a N,S‐doped carbon was considered to be designed by fixing N locations in carbon framework . The N,S‐doped carbon with the specific N form (sp‐N) was achieved by heating graphdiyne, melamine, and sulfide at 900 °C, while the simple N‐doping or S‐doping carbons were fabricated by heating graphdiyne along with melamine or sulfide, respectively.…”

“…The N,S‐doped carbon with the specific N form (sp‐N) was achieved by heating graphdiyne, melamine, and sulfide at 900 °C, while the simple N‐doping or S‐doping carbons were fabricated by heating graphdiyne along with melamine or sulfide, respectively. The N,S‐doping carbonpyrolyzed at 900 °C delivered the lowest overpotential of 299 mV at 10 mA cm −2 as compared to N‐doping (314 mV at 10 mA cm −2 ) and S‐doping carbons (>320 mV at 10 mA cm −2 ) (Figure d) . Furthermore, the N,S‐doping carbon pyrolyzed at 900 °C showed a negligible decay current after 20000 s under the chronoamperometric test.…”

Probing the active sites of site-specific nitrogen doping in metal-free graphdiyne for electrochemical oxygen reduction reactions

“…Nowadays, compared with the well-studied carbon skeletons formed by sp 2 -and sp 3 -hybridized chemical bonds (e.g., graphene, carbon nanotubes and fullerenes) [37], novel carbon allotropes with topological ordered sp-and sp 2 -hybridized carbon network structure have gained increasing attention for their unique structures and tunable electronic properties [38][39][40]. As a first synthesized member in graphynes (GYs) family [41], graphdiyne (GDY) is constructed by inserting two ethynyl units (-CC-) between two neighboring aromatic rings, which can be thought of a twodimensional (2D) plane with periodically distributed pores [42].…”