RuxSe@MoS2 hybrid as a highly efficient electrocatalyst toward hydrogen evolution reaction

Optimizing water dissociation energy and hydrogen adsorption Gibbs free energy of active sites through redistributing charges in heterostructures are a promising strategy for improving alkaline hydrogen evolution reaction (HER). Herein,...

Download Full-text

Electrochemically Induced In-Situ Generated Co(OH)2 Nanoplates to Promote the Volmer Process Toward Efficient Alkaline Hydrogen Evolution Reaction

10.26434/chemrxiv.12636974 ◽

2020 ◽

Author(s):

Hong Liu ◽

Jian-Jun Wang ◽

Li-Wen Jiang ◽

Yuan Huang ◽

Bing Bing Chen ◽

...

Keyword(s):

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Active Sites ◽

Water Electrolysis ◽

Water Dissociation ◽

Alkaline Water Electrolysis ◽

Additional Water ◽

Dissociation Step ◽

Insight Into

Hydrogen production via alkaline water electrolysis is of significant interest. However, the additional water dissociation step makes the Volmer step a relatively more sluggish kinetics and consequently leads to a slower reaction rate than that in acidic solution. Herein, we demonstrate an effective strategy that Co(OH)2 can promote the Volmer process by accelerating water dissociation and enhance the electrocatalytic performance of CoP toward alkaline hydrogen evolution reaction. The Co(OH)2 nanoplates are electrochemically induced in-situ generated to form a nanotree-like structure with porous CoP nanowires, endowing the hybrid electrocatalyst with superior charge transportation, more exposed active sites, and enhanced reaction kinetics. This strategy may be extended to <a></a><a>other phosphides and chalcogenides </a>and provide insight into the design and fabrication of efficient alkaline HER catalysts.

Download Full-text

Electrochemically Induced In-Situ Generated Co(OH)2 Nanoplates to Promote the Volmer Process Toward Efficient Alkaline Hydrogen Evolution Reaction

10.26434/chemrxiv.12636974.v1 ◽

2020 ◽

Author(s):

Hong Liu ◽

Jian-Jun Wang ◽

Li-Wen Jiang ◽

Yuan Huang ◽

Bing Bing Chen ◽

...

Keyword(s):

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Active Sites ◽

Water Electrolysis ◽

Water Dissociation ◽

Alkaline Water Electrolysis ◽

Additional Water ◽

Dissociation Step ◽

Insight Into

Hydrogen production via alkaline water electrolysis is of significant interest. However, the additional water dissociation step makes the Volmer step a relatively more sluggish kinetics and consequently leads to a slower reaction rate than that in acidic solution. Herein, we demonstrate an effective strategy that Co(OH)2 can promote the Volmer process by accelerating water dissociation and enhance the electrocatalytic performance of CoP toward alkaline hydrogen evolution reaction. The Co(OH)2 nanoplates are electrochemically induced in-situ generated to form a nanotree-like structure with porous CoP nanowires, endowing the hybrid electrocatalyst with superior charge transportation, more exposed active sites, and enhanced reaction kinetics. This strategy may be extended to <a></a><a>other phosphides and chalcogenides </a>and provide insight into the design and fabrication of efficient alkaline HER catalysts.

Download Full-text

Surface Modifications of 2D-Ti3C2O2 by Nonmetal Doping for Obtaining High Hydrogen Evolution Reaction Activity: A Computational Approach

Catalysts ◽

10.3390/catal11020161 ◽

2021 ◽

Vol 11 (2) ◽

pp. 161

Author(s):

Fangtao Li ◽

Xiaoxu Wang ◽

Rongming Wang

Keyword(s):

Catalytic Activity ◽

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Active Sites ◽

High Performance ◽

Hydrogen Adsorption ◽

Low Cost ◽

Level Shift ◽

High Hydrogen ◽

Catalytic Active Sites

As a typical two-dimensional (2D) MXene, Ti3C2O2 has been considered as a potential material for high-performance hydrogen evolution reaction (HER) catalyst, due to its anticorrosion and hydrophilic surface. However, it is still a challenge to improve the Ti3C2O2 surficial HER catalytic activity. In this work, we investigated the HER activity of Ti3C2O2 after the surface was doped with S, Se, and Te by the first principles method. The results indicated that the HER activity of Ti3C2O2 is improved after being doped with S, Se, Te because the Gibbs free energy of hydrogen adsorption (ΔGH) is increased from −2.19 eV to 0.08 eV. Furthermore, we also found that the ΔGH of Ti3C2O2 increased from 0.182 eV to 0.08 eV with the doping concentration varied from 5.5% to 16.7%. The HER catalytic activity improvement of Ti3C2O2 is attributed to the local crystal structure distortion in catalytic active sites and Fermi level shift leads to the p-d orbital hybridization. Our results pave a new avenue for preparing a low-cost and high performance HER catalyst.

Download Full-text

Theoretical Insights into the Hydrogen Evolution Reaction on the Ni3N Electrocatalyst

Catalysts ◽

10.3390/catal11060716 ◽

2021 ◽

Vol 11 (6) ◽

pp. 716

Author(s):

Russell W. Cross ◽

Sachin R. Rondiya ◽

Nelson Y. Dzade

Keyword(s):

Hydrogen Evolution ◽

Water Splitting ◽

Hydrogen Evolution Reaction ◽

Density Functional ◽

Hydrogen Adsorption ◽

Water Dissociation ◽

Metallic Nickel ◽

Surface Stability ◽

Adsorption Sites ◽

Surface Energies

Ni-based catalysts are attractive alternatives to noble metal electrocatalysts for the hydrogen evolution reaction (HER). Herein, we present a dispersion-corrected density functional theory (DFT-D3) insight into HER activity on the (111), (110), (001), and (100) surfaces of metallic nickel nitride (Ni3N). A combination of water and hydrogen adsorption was used to model the electrode interactions within the water splitting cell. Surface energies were used to characterise the stabilities of the Ni3N surfaces, along with adsorption energies to determine preferable sites for adsorbate interactions. The surface stability order was found to be (111) < (100) < (001) < (110), with calculated surface energies of 2.10, 2.27, 2.37, and 2.38 Jm−2, respectively. Water adsorption was found to be exothermic at all surfaces, and most favourable on the (111) surface, with Eads = −0.79 eV, followed closely by the (100), (110), and (001) surfaces at −0.66, −0.65, and −0.56 eV, respectively. The water splitting reaction was investigated at each surface to determine the rate determining Volmer step and the activation energies (Ea) for alkaline HER, which has thus far not been studied in detail for Ni3N. The Ea values for water splitting on the Ni3N surfaces were predicted in the order (001) < (111) < (110) < (100), which were 0.17, 0.73, 1.11, and 1.60 eV, respectively, overall showing the (001) surface to be most active for the Volmer step of water dissociation. Active hydrogen adsorption sites are also presented for acidic HER, evaluated through the ΔGH descriptor. The (110) surface was shown to have an extremely active Ni–N bridging site with ΔGH = −0.05 eV.

Download Full-text

MOFs-derived ruthenium-doped amorphous molybdenum dioxide hybrid for highly efficient hydrogen evolution reaction in alkaline media

Chemical Communications ◽

10.1039/d1cc05683b ◽

2021 ◽

Author(s):

Ji-Yuan Han ◽

Sheng-Hao Cai ◽

Ji-Yu Zhu ◽

Shuang Yang ◽

Ji-Sen Li

Keyword(s):

Graphene Oxide ◽

Synergistic Effect ◽

Reduced Graphene Oxide ◽

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Active Sites ◽

Alkaline Media ◽

Molybdenum Dioxide ◽

Highly Efficient ◽

Reduced Graphene

Ruthenium-doped amorphous molybdenum dioxide coupled with reduced graphene oxide hybrid (Ru-MoO2@PC/rGO) is synthesized using POMOF/GO as precursor. Benefitting from the synergistic effect of numerous exposed active sites, Ru dopants, and...

Download Full-text

Engineering of Ru/Ru2P interfaces superior to Pt active sites for catalysis of the alkaline hydrogen evolution reaction

Journal of Materials Chemistry A ◽

10.1039/c8ta11635k ◽

2019 ◽

Vol 7 (10) ◽

pp. 5621-5625 ◽

Cited By ~ 19

Author(s):

Zhao Liu ◽

Zhe Li ◽

Jing Li ◽

Jie Xiong ◽

Shunfa Zhou ◽

...

Keyword(s):

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Active Sites ◽

Synergistic Effects ◽

Water Dissociation ◽

Proton Reduction ◽

Mass Activity

Based on the synergistic effects of Ru on water dissociation and Ru2P on proton reduction, Ru/Ru2P interfaces were engineered in situ, and the mass activity of the new catalyst for the alkaline HER was doubled compared to Pt/C.

Download Full-text

Tailoring Water Dissociation Energy by Platinum Single-Atom Catalyst Coupled with Transition Metal/metal Oxide Heterostructure for Accelerating Alkaline Hydrogen Evolution Reaction

10.21203/rs.3.rs-155535/v1 ◽

2021 ◽

Author(s):

Changbao Han ◽

Kailing Zhou ◽

Qianqian Zhang ◽

Jingbing Liu ◽

Hui Yan ◽

...

Keyword(s):

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Dissociation Energy ◽

Active Sites ◽

Alkaline Media ◽

Water Dissociation ◽

High Mass ◽

Single Atom ◽

Adsorption Affinity ◽

Metal Metal

Abstract High-activity catalysts in alkaline media are compelling for durable hydrogen evolution reaction (HER). Single-atom catalysts (SACs) provide an effective approach to reduce the amount of precious metals meanwhile maintain their catalytic activity. However, the sluggish activity of SACs for water dissociation in alkaline media has extremely hampered advances in highly efficient hydrogen production. Herein, we developed a platinum SAC immobilized NiO/Ni heterostructure (PtSA-NiO/Ni) as an alkaline HER catalyst. It was found that Pt SACs coupled with NiO/Ni heterostructure enable the tunable binding abilities of hydroxyl ions (OH*) and hydrogen (H*), which efficiently tailors the water dissociation energy for accelerating alkaline HER. In particular, the dual active sites consisting of metallic Ni sites and O vacancies modified NiO sites near the interfaces of NiO/Ni in PtSA-NiO/Ni have preferred adsorption affinity for H* and OH* groups, respectively, which efficiently lowers the energy barrier of water dissociation of Volmer step. Moreover, anchoring Pt single atoms at the interfaces of NiO/Ni heterostructure induces more free electrons on Pt sites due to the elevated occupation of the Pt 5d orbital at the Fermi level and reaches a near-zero H binding energy (ΔGH*, 0.07 eV), which further promotes the H* conversion and H2 evolution. Further enhancement of alkaline HER performance was achieved by constructing PtSA-NiO/Ni nanosheets on the Ag nanowires to form a hierarchical three-dimensional (3D) morphology that provides abundant active sites and accessible channels for charge transfer and mass transport. Consequently, the fabricated PtSA-NiO/Ni catalyst displays extremely high alkaline HER performances with a quite high mass activity of 20.6 A mg-1 for Pt at the overpotential of 100 mV, which is 41 times greater than that of the commercial Pt/C catalyst, significantly outperforming the reported catalysts.

Download Full-text