Hydrogen Evolution Activity of Ruthenium Phosphides Encapsulated in Nitrogen‐ and Phosphorous‐Codoped Hollow Carbon Nanospheres

Abstract

RuP nanoparticles (NPs) encapsulated in uniform N,P-codoped hollow carbon nanospheres (RuP @NPC) have been synthesized through a facile route in which aniline-pyrrole copolymer nanospheres are used to disperse Ru ions followed by a gas phosphorization process. The as-prepared RuP @NPC exhibits a uniform core-shell hollow nanospherical structure with RuP NPs as the core and N,P-codoped carbon (NPC) as the shell. This strategy integrates many advantages of hollow nanostructures, which provide a conductive substrate and the doping of a nonmetal element. At high temperatures, the obtained thin NPC shell can not only protect the highly active phase of RuP NPs from aggregation and corrosion in the electrolyte but also allows variation in the electronic structures to improve the charge-transfer rate greatly by N,P codoping. The optimized RuP @NPC sample at 900 °C exhibits a Pt-like performance for the hydrogen evolution reaction (HER) and long-term durability in acidic, alkaline, and neutral solutions. The reaction requires a small overpotential of only 51, 74, and 110 mV at 10 mA cm in 0.5 m H SO , 1.0 m KOH, and 1.0 m phosphate-buffered saline, respectively. This work provides a new way to design unique phosphide-doped carbon heterostructures through an inorganic-organic hybrid method as excellent electrocatalysts for HER.

Ru–Ru2PΦNPC and NPC@RuO2 Synthesized via Environment‐Friendly and Solid‐Phase Phosphating Process by Saccharomycetes as N/P Sources and Carbon Template for Overall Water Splitting in Acid Electrolyte

“…Furthermore, the Ru–Ru 2 PΦNPC also performed high HER catalytic activities in 1.0 m KOH (onset potential of −10 mV, overpotential of 46 mV@10 mA cm −2 and Tafel slope of 39.75 mV dec −1 ) and 1.0 m phosphate buffered saline (onset potential of 0 mV, overpotential of 41 mV@10 mA cm −2 , and Tafel slope of 56.79 mV dec −1 ) (Figure S17, Supporting Information). The remarkable HER performance of Ru–Ru 2 PΦNPC (η 10 = 42 mV, Tafel slope = 39.75 mV dec −1 ) was better than, or at least comparable to, those of Ru‐based catalysts including Ru/GLC (35 mV, 46 mV dec −1 ), RuP 2 @NPC (38 mV, 38 mV dec −1 ),9b Ru–MoO 2 nanocomposites (55 mV, 44 mV dec −1 ), RuP 2 (55 mV, 34 mV dec −1 ) and RuP x @NPC (51 mV, 46 mV dec −1 ), and Ni@Ni 2 P‐Ru (51 mV, 35 mV dec −1 ) in acidic solution.…”

Ruthenium Nanoparticles for Catalytic Water Splitting

“…of phosphorus and the increase in corrosion resistance of the nanomaterials at acidic pH induced by the presence of phosphorus; the latter improves their stability . Thus, for Ru NPs, the introduction of P has been shown to be extremely productive in HER catalysis under acidic conditions, but also at neutral and basic pH, normally generating composite systems in which the effect of the C‐based material is essential for preventing aggregation and for tuning of the electronic properties of the NPs . For example, very stable HER catalytic systems at all pH values have been obtained by encapsulating RuP x NPs inside N,P‐doped C shells (RuP 2 @NPC; Table , entry 13; Table , entry 11) and nanospheres (RuP x @NPC; Table , entry 9; Table , entry 7).…”

“…[91] Thus, for Ru NPs, the introduction of Ph as been shownt ob ee xtremelyp roductivei nH ER catalysis under acidic conditions, but also at neutrala nd basic pH, normally generating composite systems in which the effecto ft he C-based material is essential for preventing aggregation and for tuning of the electronic properties of the NPs. [92][93][94][95] For example,v ery stable HER catalytic systemsa ta ll pH values have been obtained by encapsulating RuP x NPs inside N,P-doped C shells [93] (RuP 2 @NPC;T able 3, entry 13;T able 4, entry 11)a nd nanospheres [92] (RuP x @NPC;T able 3, entry 9; Ta ble 4, entry 7). Twoh ighly active systems concerning the use of these pH-versatile RuP x NPs on C-based supports have been reported recently by Li et al, [94,95] in whicht he synergistic interactions between the NPs and C-baseds upport provoke an increasei n electron mobility and ar edistributiono fc harge density between them;t he latter inducesa no ptimal hydrogen adsorption energy close to zero, and thus, highly active HER electrocatalysts.…”

Synthesis of Ru‐Doped VN by a Soft‐Urea Pathway as an Efficient Catalyst for Hydrogen Evolution

“…However, the unfavorable aggregation and coarsening of Ru in synthesizing process have significantly affected its activity and stability . To overcome this dilemma, some proper supports, such as carbon materials, metal oxide, and hydroxides, are introduced to anchor and stabilize ultra‐small Ru species . More than acting as anchoring sites, these supports also have a significant impact on the catalyst activity and stability of Ru species …”

“…[23,24] To overcome this dilemma, some proper supports, such as carbon materials, metal oxide, and hydroxides, are introduced to anchor and stabilize ultrasmall Ru species. [25][26][27][28][29] More than acting as anchoring sites, these supports also have a significant impact on the catalyst activity and stability of Ru species. [30,31] Transition metal nitrides (TMNs), known as its special electronic structure, have attracted considerable attention in energy fields.…”