scholarly journals Correlating hydrogen oxidation and evolution activity on platinum at different pH with measured hydrogen binding energy

2015 ◽  
Vol 6 (1) ◽  
Author(s):  
Wenchao Sheng ◽  
Zhongbin Zhuang ◽  
Minrui Gao ◽  
Jie Zheng ◽  
Jingguang G. Chen ◽  
...  
Keyword(s):  
Binding Energy ◽  
Hydrogen Oxidation ◽  
Hydrogen Binding

scholarly journals Universal dependence of hydrogen oxidation and evolution reaction activity of platinum-group metals on pH and hydrogen binding energy

2016 ◽  
Vol 2 (3) ◽  
pp. e1501602 ◽  
Author(s):  
Jie Zheng ◽  
Wenchao Sheng ◽  
Zhongbin Zhuang ◽  
Bingjun Xu ◽  
Yushan Yan
Keyword(s):  
Binding Energy ◽  
Hydrogen Oxidation ◽  
Ph Dependence ◽  
Platinum Group Metals ◽  
Hydrogen Binding ◽  
Hydrogen Oxidation Reaction ◽  
Promoting Effect ◽  
Onset Potential ◽  
Co Stripping ◽  
Platinum Group

Understanding how pH affects the activity of hydrogen oxidation reaction (HOR) and hydrogen evolution reaction (HER) is key to developing active, stable, and affordable HOR/HER catalysts for hydroxide exchange membrane fuel cells and electrolyzers. A common linear correlation between hydrogen binding energy (HBE) and pH is observed for four supported platinum-group metal catalysts (Pt/C, Ir/C, Pd/C, and Rh/C) over a broad pH range (0 to 13), suggesting that the pH dependence of HBE is metal-independent. A universal correlation between exchange current density and HBE is also observed on the four metals, indicating that they may share the same elementary steps and rate-determining steps and that the HBE is the dominant descriptor for HOR/HER activities. The onset potential of CO stripping on the four metals decreases with pH, indicating a stronger OH adsorption, which provides evidence against the promoting effect of adsorbed OH on HOR/HER.

scholarly journals Hydrogen Oxidation on Ni-Based Electrocatalysts: The Effect of Metal Doping

2018 ◽  
Author(s):  
Elena S. Davydova ◽  
Jérémie Zaffran ◽  
Kapil Dhaka ◽  
Maytal Caspary Toroker ◽  
Dario R. Dekel
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Binding Energy ◽  
Density Functional ◽  
Hydrogen Oxidation ◽  
Ni Catalyst ◽  
Hydrogen Chemisorption ◽  
Hydrogen Binding ◽  
X Ray ◽  
Transmission Electron

Carbon supported nanoparticles of monometallic Ni catalyst and binary Ni-Transition Metal (Ni-TM/C) electrocatalytic composites were synthesized via chemical reduction method, where TM stands for the doping elements Fe, Co, and Cu. The chemical composition, structure and morphology of the Ni-TM/C materials were characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffractometry (XRD), transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM) and energy-dispersive X-ray spectroscopy (EDS). The electrochemical properties towards hydrogen oxidation reaction in alkaline medium were studied using the rotating disc electrode and cycling voltammetry methods. A significant role of the TM dopant in the promotion of the hydrogen electrooxidation kinetics of the binary Ni-TM/C materials were revealed. A record-high in exchange current density value of 0.060 mA cm2Ni was measured for Ni3Fe1/C, whereas the monometallic Ni/C counterpart has only shown 0.039 mA cm2Ni. In order to predict the feasibility of the electrocatalysts for hydrogen chemisorption, density functional theory was applied to calculate the hydrogen binding energy and hydroxide binding energy values for bare Ni and Ni3TM1.

scholarly journals Hydrogen Oxidation on Ni-Based Electrocatalysts: The Effect of Metal Doping

Catalysts ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 454 ◽  
Author(s):  
Elena Davydova ◽  
Jérémie Zaffran ◽  
Kapil Dhaka ◽  
Maytal Toroker ◽  
Dario Dekel
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Binding Energy ◽  
Density Functional ◽  
Hydrogen Oxidation ◽  
Ni Catalyst ◽  
Hydrogen Chemisorption ◽  
Hydrogen Binding ◽  
X Ray ◽  
Transmission Electron

Carbon supported nanoparticles of monometallic Ni catalyst and binary Ni-Transition Metal (Ni-TM/C) electrocatalytic composites were synthesized via the chemical reduction method, where TM stands for the doping elements Fe, Co, and Cu. The chemical composition, structure and morphology of the Ni-TM/C materials were characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM) and energy-dispersive X-ray spectroscopy (EDS). The electrochemical properties towards hydrogen oxidation reaction in alkaline medium were studied using the rotating disc electrode and cycling voltammetry methods. A significant role of the TM dopants in the promotion of the hydrogen electrooxidation kinetics of the binary Ni-TM/C materials was revealed. A record-high in exchange current density value of 0.060 mA cm2Ni was measured for Ni3Fe1/C, whereas the monometallic Ni/C counterpart has only shown 0.039 mA cm2Ni. In order to predict the feasibility of the electrocatalysts for hydrogen chemisorption, density functional theory was applied to calculate the hydrogen binding energy and hydroxide binding energy values for bare Ni and Ni3TM1.

Uniform Pd0.33Ir0.67 nanoparticles supported on nitrogen-doped carbon with remarkable activity toward the alkaline hydrogen oxidation reaction

2019 ◽  
Vol 7 (7) ◽  
pp. 3161-3169 ◽  
Author(s):  
Yuanyuan Cong ◽  
Ian T. McCrum ◽  
Xueqiang Gao ◽  
Yang Lv ◽  
Shu Miao ◽  
...  
Keyword(s):  
Oxidation Reaction ◽  
Hydrogen Oxidation ◽  
Hydrogen Binding ◽  
Hydrogen Oxidation Reaction ◽  
Nitrogen Doped ◽  
Electrocatalytic Performance ◽  
Nitrogen Doped Carbon

The excellent alkaline HOR electrocatalytic performance on Pd1−xIrx/N-C arises from the appropriate strength of hydrogen binding and the strongest oxophilic property.

Silicon-Hydrogen Bonds in Boron and Phosphorous Doped Polycrystalline Silicon Thin Films

2004 ◽  
Vol 808 ◽  
Author(s):  
R. Saleh ◽  
N. H. Nickel
Keyword(s):  
Binding Energy ◽  
Polycrystalline Silicon ◽  
Binding Energies ◽  
Vibration Modes ◽  
Laser Crystallization ◽  
Hydrogen Binding ◽  
Local Vibration ◽  
Silicon Thin Films ◽  
The One ◽  
Hydrogen Effusion

ABSTRACTHydrogen bonding in laser crystallized boron and phosphorous doped polycrystalline silicon is investigated using Raman spectroscopy and hydrogen effusion measurements. During laser crystallization the intensity of the local vibration modes near 2000 and 2100 cm−1 decreases. The intensity of vibration mode at 2000 cm−1 decreases faster than the one at 2100 cm−1. From H effusion measurements, the hydrogen density-of-states (H DOS) distribution is derived. For undoped amorphous silicon the H DOS exhibits two prominent peaks at hydrogen binding energies of E– μH = –1.1 and –1.5 eV. In B doped a-Si:H the peak at –1.1 eV is less pronounced while in P doped a-Si:H the H binding energy increases by about 0.1 eV. In all samples laser crystallization causes an increase of the H binding energy by about 0.2 – 0.3 eV. However, the peaks in the H DOS observed in B-doped samples are preserved during laser crystallization.

Different Approach to Estimation of Hydrogen-Binding Energy in Nanospace-Engineered Activated Carbons

2013 ◽  
Vol 118 (2) ◽  
pp. 955-961 ◽  
Author(s):  
L. Firlej ◽  
M. Beckner ◽  
J. Romanos ◽  
P. Pfeifer ◽  
B. Kuchta
Keyword(s):  
Binding Energy ◽  
Activated Carbons ◽  
Hydrogen Binding

Hydrogen Structures in Heavily Hydrogenated Crystalline and Amorphous Silicon

1998 ◽  
Vol 513 ◽  
Author(s):  
W. B. Jackson ◽  
A. Franz ◽  
Y. Chabal ◽  
M. K. Weldon ◽  
H.-C. Jin ◽  
...  
Keyword(s):  
Binding Energy ◽  
Ir Spectra ◽  
Amorphous Silicon ◽  
Deformation Mode ◽  
Hydrogen Binding ◽  
Transport Barrier ◽  
Surface Evolution ◽  
Amorphous Si ◽  
Two Peaks ◽  
Strong Mode

ABSTRACTThe hydrogen binding energy distribution and IR spectra of hydrogen platelets in c-Si have been measured and compared to H in other forms of silicon including hydrogenated polycrystalline and amorphous Si. The binding distribution for platelet containing samples, determined using H evolution, exhibits two peaks: a bulk peak at 1.8–1.9 eV below the transport barrier, and a second possibly surface related peak 1.8–1.9 eV below the surface evolution barrier. The bulk peak grows at 250C and is consistent with calculated energies for platelet structures. The same two evolution peaks are found in hydrogenated polycrystalline Si and amorphous silicon. The IR spectra for heavily hydrogenated c-Si are dominated by the stretching modes at 2076 and 2128 cm-1. Most surprisingly there appears to be a strong mode at 856 cm-1 which is associated with a deformation mode of SiH3. Even more surprising, this SiH3 856 cm-1 mode remains until 550 C indicating that the SiH3 containing structures are rather stable.

scholarly journals An Efficient Nickel Hydrogen Oxidation Catalyst for Hydroxide Exchange Membrane Fuel Cells

2021 ◽  
Author(s):  
Weiyan Ni ◽  
Teng Wang ◽  
Florent Heroguel ◽  
Anna Krammer ◽  
seunghwa lee ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Hydrogen Oxidation ◽  
Platinum Group Metal ◽  
Carbon Support ◽  
Oxidation Catalyst ◽  
Electronic Interaction ◽  
Ni Nanoparticles ◽  
Hydrogen Binding ◽  
Hydrogen Oxidation Reaction ◽  
Exchange Membrane

The hydroxide exchange membrane fuel cell (HEMFC) is a promising energy conversion technology, but it is limited by the need of platinum-group-metal (PGM) electrocatalysts, especially for the hydrogen oxidation reaction (HOR). Here we report a Ni-based HOR catalyst that exhibits an electrochemical surface area-normalized exchange current density of 70 μA/cm2, the highest among PGM-free catalysts. The catalyst comprises of Ni nanoparticles embedded in a nitrogen-doped carbon support. According to X-ray and ultraviolet photoelectron spectroscopy as well as H2 chemisorption, the electronic interaction between the Ni nanoparticles and its support leads to an optimal hydrogen binding energy, which is the likely origin of its high activity. PGM-free HEMFCs employing this Ni HOR catalyst give a peak power density of 450 mW/cm2, up to 6 times higher than previous best-performing analogous. This work demonstrates the feasibility of efficient PGM-free HEMFCs.<br>

Sign in / Sign up

Export Citation Format

Share Document