Mixture Phases Engineering of PtFe Nanofoams for Efficient Hydrogen Evolution

Abstract

Phase engineering is a promising but challenging approach to construct PtFe‐based catalysts with efficient hydrogen evolution reaction (HER) performance. Herein, the authors successfully synthesize PtFe nanofoams with face center cubic (fcc) phase, with simple cubic crystalline (scc) phase and with the mixture phases of fcc and scc phases (PtFe‐mix) by hydrogen‐assisted calcination for the first time. By benchmarking the HER activity, PtFe‐mix exhibits excellent activity in 1.0 m KOH, requiring an overpotential of 28 mV to achieve 10 mA cm−2, which is better than the commercial Pt/C (34 mV). PtFe‐mix also possesses remarkable stability up to 24 h. Density functional theory calculations further verify that PtFe‐mix shows a more suitable d‐band center and lower energy barrier for the initial water dissociation, facilitating the HER process. This work provides a meaningful strategy to design PtFe‐based catalysts with efficient activity for hydrogen evolution.

Sun, heat and electricity. A comprehensive study of non‐pollutant alternatives to produce green hydrogen

“…Current novel alkaline approaches focus on composite membranes like polybenzimidazole incorporating graphitic carbon nitride nanosheets (PBI/g‐C 3 N 4 ) and pore‐filling polytetrafluoroethylene/layered double hydroxide (PTFE/LHD), 230‐234 and Ru nanoclusters on nitrogen‐doped graphene as catalyst 235 . For AEM, Ni‐based catalysts and polysulfone (PSF) or polystyrene (PS) hydrocarbon polymer backbone membranes they are the most accepted in more recent developments 236‐239 …”

Plasma synthesis of defect-rich flexible carbon cloth decorated with PtRu alloyed nanoclusters for highly efficient pH-universal electrocatalytic hydrogen evolution

“…The Pt 5d orbitals are almost completely filled, and strong Pauli repulsion occurs when they are overlapped with water molecular orbitals, resulting in inefficient HO–H bond cleavage (Volmer step) on the Pt surface. 14,15 Therefore, Pt generally has sluggish HER kinetics in alkaline electrolytes. 4,16–18…”

Experimental and Theoretical Insights into Enhanced Hydrogen Evolution over PtCo Nanoalloys Anchored on a Nitrogen-Doped Carbon Matrix

“…18−25 Up to now, a series of PtM (M = Co, Ni, Fe, Cu, etc.) alloys have been developed as low Pt-based HER electrocatalysts, [18][19][20][21][22]24 resulting in Co being one of the most promising elements to realize synergistic effect toward the HER. 26−28 Apart from the enhancement of intrinsic electrocatalysis through component optimization, it is equally essential to decrease the size of Pt-based alloys to nanoscale, thereby maximizing the number of exposed active sites.…”

“…Alloying Pt with 3d transition metals provides an effective strategy to reduce the Pt usage and improve the intrinsic HER catalysis with greatly increased Pt utilization efficiency. − Up to now, a series of PtM (M = Co, Ni, Fe, Cu, etc.) alloys have been developed as low Pt-based HER electrocatalysts, − , resulting in Co being one of the most promising elements to realize synergistic effect toward the HER. − Apart from the enhancement of intrinsic electrocatalysis through component optimization, it is equally essential to decrease the size of Pt-based alloys to nanoscale, thereby maximizing the number of exposed active sites. ,− Nevertheless, with the downsizing of PtM nanoparticles, how to stabilize these nanoalloys becomes another challenge needed to be resolved .…”

“…Alloying Pt with 3d transition metals provides an effective strategy to reduce the Pt usage and improve the intrinsic HER catalysis with greatly increased Pt utilization efficiency. − Up to now, a series of PtM (M = Co, Ni, Fe, Cu, etc.) alloys have been developed as low Pt-based HER electrocatalysts, − , resulting in Co being one of the most promising elements to realize synergistic effect toward the HER. − Apart from the enhancement of intrinsic electrocatalysis through component optimization, it is equally essential to decrease the size of Pt-based alloys to nanoscale, thereby maximizing the number of exposed active sites. ,− Nevertheless, with the downsizing of PtM nanoparticles, how to stabilize these nanoalloys becomes another challenge needed to be resolved . To this end, in situ growth of well-dispersed PtM nanoalloys on N-doped carbon matrix serves as another rational design strategy, which can not only avoid the aggregation of alloy nanoparticles but also ensure strong coupling between the active PtM nanoparticles and the carbon substrate with rapid electron transfer. − Therefore, constructing uniform Pt-based nanoalloys grown in situ on the N-doped carbon matrix is anticipated to act as a more efficient and durable electrocatalyst than commercial 20 wt % Pt/C benchmark, yet it remains to be testified.…”