Solvent-mediated crystalline phases of NixSy anchored on rGO sheets as electrocatalysts for hydrogen evolution application

A facile, one-pot solvent-mediated hydrothermal process was adopted to prepare nickel sulfide nanoparticles decorated on reduced graphene oxide (NixSy/rGO) as electrocatalysts for hydrogen evolution reaction (HER). The designed solvent (ethylene glycol and deionized water) played a decisive role in controlling both crystalline phase and morphology of NixSy/rGO composites, leading to pure [Formula: see text]-NiS nanoparticles uniformly distributed on rGO sheets under suitable volume ratio of ethylene glycol and deionized water (2:1). The optimized [Formula: see text]-NiS/rGO showed prominent HER catalytic performance with a rather small Tafel slope of 93[Formula: see text]mV/decade and prominent current density of 10[Formula: see text]mA/cm2 at the overpotential of 177[Formula: see text]mV in alkaline environments when compared to pristine [Formula: see text]-NiS and NiS2/rGO catalysts. The excellent catalytic performance and long-term durability even after 8000 cycles confirmed the potential of [Formula: see text]-NiS/rGO composites as efficient electrocatalysts for HER in the alkaline media.

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Nitrogen Functionalization of CVD Grown Three-Dimensional Graphene Foam for Hydrogen Evolution Reactions in Alkaline Media

Materials ◽

10.3390/ma14174952 ◽

2021 ◽

Vol 14 (17) ◽

pp. 4952

Author(s):

Daniela Ion-Ebrașu ◽

Radu Dorin Andrei ◽

Stanică Enache ◽

Simona Căprărescu ◽

Constantin Cătălin Negrilă ◽

...

Keyword(s):

Hydrogen Evolution ◽

Photoelectron Spectroscopy ◽

Hydrothermal Process ◽

Three Dimensional ◽

Chemical Vapor ◽

Alkaline Media ◽

Active Nitrogen ◽

Graphene Foam ◽

Graphene Layers ◽

Nitrogen Doped

Three-dimensional graphene foam (3D-GrFoam) is a highly porous structure and sustained lattice formed by graphene layers with sp2 and sp3 hybridized carbon. In this work, chemical vapor deposition (CVD)—grown 3D-GrFoam was nitrogen-doped and platinum functionalized using hydrothermal treatment with different reducing agents (i.e., urea, hydrazine, ammonia, and dihydrogen hexachloroplatinate (IV) hydrate, respectively). X-ray photoelectron spectroscopy (XPS) survey showed that the most electrochemically active nitrogen-doped sample (GrFoam3N) contained 1.8 at % of N, and it exhibited a 172 mV dec−1 Tafel plot associated with the Volmer–Heyrovsky hydrogen evolution (HER) mechanism in 0.1 M KOH. By the hydrothermal process, 0.2 at % of platinum was anchored to the graphene foam surface, and the resultant sample of GrFoamPt yielded a value of 80 mV dec−1 Tafel associated with the Volmer–Tafel HER mechanism. Furthermore, Raman and infrared spectroscopy analysis, as well as scanning electron microscopy (SEM) were carried out to understand the structure of the samples.

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One-pot synthesis of alloyed PdAg networks as efficient catalysts of ethylene glycol electro-oxidation in alkaline media

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2020.157075 ◽

2021 ◽

Vol 854 ◽

pp. 157075

Author(s):

Fangfang Ren ◽

Lijie Xu ◽

Hui Xu ◽

Yiwen Tang ◽

Zongtang Liu ◽

...

Keyword(s):

Ethylene Glycol ◽

Alkaline Media ◽

One Pot ◽

One Pot Synthesis ◽

Electro Oxidation

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One-pot synthesized boron-doped RhFe alloy with enhanced catalytic performance for hydrogen evolution reaction

Applied Catalysis B Environmental ◽

10.1016/j.apcatb.2018.02.034 ◽

2018 ◽

Vol 230 ◽

pp. 58-64 ◽

Cited By ~ 57

Author(s):

Lishang Zhang ◽

Jiajia Lu ◽

Shibin Yin ◽

Lin Luo ◽

Shengyu Jing ◽

...

Keyword(s):

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Catalytic Performance ◽

One Pot ◽

Boron Doped

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N Coupling with S-Coordinated Ru Nanoclusters for Highly Efficient Hydrogen Evolution in Alkaline Media

Journal of Materials Chemistry A ◽

10.1039/d1ta02568f ◽

2021 ◽

Author(s):

Chengfei Li ◽

Jia-Wei Zhao ◽

Ling-Jie Xie ◽

Yu Wang ◽

Haibo Tang ◽

...

Keyword(s):

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Catalytic Performance ◽

Alkaline Media ◽

Metal Nanoclusters ◽

Highly Efficient ◽

Active Metal

Optimizing coordination/surrounding environments of active metal nanoclusters to promote the catalytic performance of hydrogen evolution reaction (HER) in alkaline media is great important, but extremely challenge. Here, we demonstrate that...

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Precursor Investigation in the Synthesis of PtPb Nanocatalysts

MRS Proceedings ◽

10.1557/opl.2012.1736 ◽

2013 ◽

Vol 1491 ◽

Author(s):

Nathan Porter ◽

Hong Wu ◽

Minji Kong ◽

Kai Sun ◽

Amar Kumbhar ◽

...

Keyword(s):

Catalytic Activity ◽

Volume Ratio ◽

Catalytic Performance ◽

Polyol Synthesis ◽

One Pot ◽

Nucleation Stage ◽

Synthesis Technique ◽

Metal Precursor ◽

Synthetic Strategy ◽

Shape Controlled

ABSTRACTIn recent years, platinum-based single crystalline nanoalloys as nanoscale catalysts, such as Pt-M (M = Ni, Co, Fe..etc.), have exhibited improved catalytic performance due to the increase in the surface-to-volume ratio. Some Pt-M nanopolyhedra such as nanocubes and nano-octahedra have been reported with enhanced activity when being used as electrocatalysts. In order to further establish a correlation between the exposed nanocrystal facets (shapes) and their corresponding activities, a pursuit of shape-controlled nanocatalyst synthesis is essential. Although PtPb nanoalloys have been prepared using solution-based methods, few studies have highlighted their catalytic activity as a function of the nanocrystal shape. This work focuses on a modified polyol synthesis technique and an adjustment of the Pb-metal precursor, which serves as a “buffer” in the nucleation stage of the shape-controlled nanoalloy development. Using this developed synthetic strategy, shape-controlled hexagonally close-packed PtPb nanoalloys can be prepared in a one-pot synthesis without additional post-treatment. The as-prepared PtPb nanocrystals demonstrate an improved anode electrocatalytic performance.

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Cysteine-Induced Hybridization of 2D Molybdenum Disulfide Films for Efficient and Stable Hydrogen Evolution Reaction

Materials ◽

10.3390/ma14051165 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1165

Author(s):

Arunas Jagminas ◽

Paulius Gaigalas ◽

Carla Bittencourt ◽

Vaclovas Klimas

Keyword(s):

Electron Microscopy ◽

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Photoelectron Spectroscopy ◽

Hydrogen Adsorption ◽

Hydrothermal Process ◽

Linear Sweep Voltammetry ◽

One Pot ◽

Tafel Slope ◽

Highly Active

The noble, metal-free materials capable of efficiently catalyzing water splitting reactions currently hold a great deal of promise. In this study, we reported the structure and electrochemical performance of new MoS2-based material synthesized with L-cysteine. For this, a facile one-pot hydrothermal process was developed and an array of densely packed nanoplatelet-shaped hybrid species directly on a conductive substrate were obtained. The crucial role of L-cysteine was determined by numerous methods on the structure and composition of the synthesized material and its activity and stability for hydrogen evolution reaction (HER) from the acidic water. A low Tafel slope of 32.6 mV dec−1, close to a Pt cathode, was registered for the first time. The unique HER performance at the surface of this hybrid material in comparison with recently reported MoS2-based electrocatalysts was attributed to the formation of more defective 1T, 2H-MoS2/MoOx, C nanostructures with the dominant 1T-MoS2 phase and thermally degraded cysteine residues entrapped. Numerous stacks of metallic (1T-MoS2 and MoO2) and semiconducting (2H-MoS2 and MoO3) fragments relayed the formation of highly active layered nanosheets possessing a low hydrogen adsorption free energy and much greater durability, whereas intercalated cysteine fragments had a low Tafel slope of the HER reaction. X-ray photoelectron spectroscopy, scanning electron microscopy, thermography with mass spectrometry, high-resolution transmission electron microscopy, Raman spectroscopy techniques, and linear sweep voltammetry were applied to verify our findings.

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One-pot synthesis of boron-doped ordered mesoporous carbons as efficient electrocatalysts for the oxygen reduction reaction

RSC Advances ◽

10.1039/c6ra01296e ◽

2016 ◽

Vol 6 (29) ◽

pp. 24728-24737 ◽

Cited By ~ 13

Author(s):

Jianmin Su ◽

Xuecheng Cao ◽

Jiao Wu ◽

Chao Jin ◽

Jing-Hua Tian ◽

...

Keyword(s):

Catalytic Performance ◽

Reduction Reaction ◽

Alkaline Media ◽

Doping Content ◽

Mesoporous Carbons ◽

One Pot ◽

Ordered Mesoporous Carbons ◽

Boron Doped ◽

Ordered Mesoporous ◽

Excellent Catalytic Performance

Boron-doped OMCs with a high doping content of 1.17 wt% show excellent catalytic performance for ORR in alkaline media.

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One-Pot Synthesis of W2C/WS2 Hybrid Nanostructures for Improved Hydrogen Evolution Reactions and Supercapacitors

Nanomaterials ◽

10.3390/nano10081597 ◽

2020 ◽

Vol 10 (8) ◽

pp. 1597 ◽

Cited By ~ 2

Author(s):

Sajjad Hussain ◽

Iqra Rabani ◽

Dhanasekaran Vikraman ◽

Asad Feroze ◽

Muhammad Ali ◽

...

Keyword(s):

Hydrogen Evolution ◽

High Performance ◽

Hybrid Nanostructures ◽

Alkaline Media ◽

Supercapacitor Electrode ◽

One Pot ◽

Energy Applications ◽

Symmetric Supercapacitor ◽

Acidic And Alkaline Media ◽

First Time

Tungsten sulfide (WS2) and tungsten carbide (W2C) are materialized as the auspicious candidates for various electrochemical applications, owing to their plentiful active edge sites and better conductivity. In this work, the integration of W2C and WS2 was performed by using a simple chemical reaction to form W2C/WS2 hybrid as a proficient electrode for hydrogen evolution and supercapacitors. For the first time, a W2C/WS2 hybrid was engaged as a supercapacitor electrode and explored an incredible specific capacitance of ~1018 F g−1 at 1 A g−1 with the outstanding robustness. Furthermore, the constructed symmetric supercapacitor using W2C/WS2 possessed an energy density of 45.5 Wh kg−1 at 0.5 kW kg−1 power density. For hydrogen evolution, the W2C/WS2 hybrid produced the low overpotentials of 133 and 105 mV at 10 mA cm−2 with the small Tafel slopes of 70 and 84 mV dec−1 in acidic and alkaline media, respectively, proving their outstanding interfaced electrocatalytic characteristics. The engineered W2C/WS2-based electrode offered the high-performance for electrochemical energy applications.

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Facile Synthesis of Well-Dispersed Ni2P on N-Doped Nanomesh Carbon Matrix as a High-Efficiency Electrocatalyst for Alkaline Hydrogen Evolution Reaction

Nanomaterials ◽

10.3390/nano9071022 ◽

2019 ◽

Vol 9 (7) ◽

pp. 1022 ◽

Cited By ~ 1

Author(s):

Fan Yang ◽

Shuo Huang ◽

Bing Zhang ◽

Liqiang Hou ◽

Yi Ding ◽

...

Keyword(s):

Catalytic Activity ◽

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

High Efficiency ◽

Carbon Matrix ◽

Catalytic Performance ◽

Alkaline Media ◽

Mesh Structure ◽

Factors Affecting ◽

The Stability

The development of non-noble metal hydrogen evolution catalysts that can replace Pt is crucial for efficient hydrogen production. Herein, we develop a type of well-dispersed Ni2P on N-doped nanomesh carbon (NC) electrocatalyst by a facile pyrolysis method, which shows excellent hydrogen evolution reaction (HER) catalytic performance. It is rather remarkable that the overpotential of Ni2P/NC prepared under optimal proportion is 108 mV at 10 mA·cm−2 current density in 1 M KOH solution with the tafel slope of 67.3 mV·dec−1, the catalytic activity has no significant attenuation after 1000 cycles of cyclic voltammetry (CV)method. The hydrogen evolution performance of the electrocatalytic is better than most similar catalysts in alkaline media. The unique mesh structure of the carbon component in the catalyst facilitates the exposure of the active site and reduces the impedance, which improves the efficiency of electron transport as well as ensuring the stability of the hydrogen evolution reaction. In addition, we prove that nitrogen doping and pore structure are also important factors affecting catalytic activity by control experiments. Our results show that N-doped nanomesh carbon, as an efficient support, combined with Ni2P nanoparticles is of great significance for the development of efficient hydrogen evolution electrodes.

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