Lignin-Assisted Water Electrolysis for Energy-Saving Hydrogen Production With Ti/PbO2 as the Anode

Replacing the oxygen evolution reaction (OER), which is of high energy consumption and slow kinetics, with the more thermodynamically favorable reaction at the anode can reduce the electricity consumption for hydrogen production. Here we developed a lignin-assisted water electrolysis (LAWE) process by using Ti/PbO2 with high OER overpotential as the anode aimed at decreasing the energy consumption for hydrogen production. The influence of key operating parameters such as temperature and lignin concentration on hydrogen production was analyzed. Compared with alkaline water electrolysis (AWE), the anode potential can be decreased from 0.773 to 0.303 (V vs. Hg/HgO) at 10 mA/cm2 in LAWE, and the corresponding cell voltage can be reduced by 546 mV. With increasing the temperature and lignin concentration, current density and H2 production rate were efficiently promoted. Furthermore, the anode deactivation was investigated by analyzing the linear sweep voltammetry (LSV) and cyclic voltammetry (CV) tests. Results showed that the anode deactivation was affected by the temperature.

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Energy-saving hydrogen production by chlorine-free hybrid seawater splitting coupling hydrazine degradation

Nature Communications ◽

10.1038/s41467-021-24529-3 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Fu Sun ◽

Jingshan Qin ◽

Zhiyu Wang ◽

Mengzhou Yu ◽

Xianhong Wu ◽

...

Keyword(s):

Hydrogen Production ◽

Low Voltage ◽

Neutral Hydrogen ◽

Water Electrolysis ◽

High Energy ◽

Hydrogen Energy ◽

Scale Production ◽

Alkaline Water Electrolysis ◽

Self Powered ◽

Seawater Electrolysis

AbstractSeawater electrolysis represents a potential solution to grid-scale production of carbon-neutral hydrogen energy without reliance on freshwater. However, it is challenged by high energy costs and detrimental chlorine chemistry in complex chemical environments. Here we demonstrate chlorine-free hydrogen production by hybrid seawater splitting coupling hydrazine degradation. It yields hydrogen at a rate of 9.2 mol h–1 gcat–1 on NiCo/MXene-based electrodes with a low electricity expense of 2.75 kWh per m3 H2 at 500 mA cm–2 and 48% lower energy equivalent input relative to commercial alkaline water electrolysis. Chlorine electrochemistry is avoided by low cell voltages without anode protection regardless Cl– crossover. This electrolyzer meanwhile enables fast hydrazine degradation to ~3 ppb residual. Self-powered hybrid seawater electrolysis is realized by integrating low-voltage direct hydrazine fuel cells or solar cells. These findings enable further opportunities for efficient conversion of ocean resources to hydrogen fuel while removing harmful pollutants.

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Multiphysical Models for Hydrogen Production Using NaOH and Stainless Steel Electrodes in Alkaline Electrolysis Cell

Journal of Combustion ◽

10.1155/2021/6673494 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Ivan Newen Aquigeh ◽

Merlin Zacharie Ayissi ◽

Dieudonné Bitondo

Keyword(s):

Stainless Steel ◽

Hydrogen Production ◽

Supporting Electrolyte ◽

Cell Voltage ◽

Water Electrolysis ◽

Maximum Error ◽

Electrolysis Cell ◽

Alkaline Water Electrolysis ◽

Interelectrode Gap ◽

Alkaline Electrolysis

The cell voltage in alkaline water electrolysis cells remains high despite the fact that water electrolysis is a cleaner and simpler method of hydrogen production. A multiphysical model for the cell voltage of a single cell electrolyzer was realized based on a combination of current-voltage models, simulation of electrolyzers in intermittent operation (SIMELINT), existing experimental data, and data from the experiment conducted in the course of this work. The equipment used NaOH as supporting electrolyte and stainless steel as electrodes. Different electrolyte concentrations, interelectrode gaps, and electrolyte types were applied and the cell voltages recorded. Concentrations of 60 wt% NaOH produced lowest range of cell voltage (1.15–2.67 V); an interelectrode gap of 0.5 cm also presented the lowest cell voltage (1.14–2.71 V). The distilled water from air conditioning led to a minimum cell voltage (1.18–2.78 V). The water from a factory presented the highest flow rate (12.48 × 10−1cm3/min). It was found that the cell voltage of the alkaline electrolyzer was reduced considerably by reducing the interelectrode gap to 0.5 cm and using electrolytes that produce less bubbles. A maximum error of 1.5% was found between the mathematical model and experimental model, indicating that the model is reliable.

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Towards the Hydrogen Economy—A Review of the Parameters That Influence the Efficiency of Alkaline Water Electrolyzers

Energies ◽

10.3390/en14113193 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3193

Author(s):

Ana L. Santos ◽

Maria-João Cebola ◽

Diogo M. F. Santos

Keyword(s):

Energy Content ◽

Water Electrolysis ◽

High Energy ◽

Operating Conditions ◽

Energy Sources ◽

Alkaline Water Electrolysis ◽

Alkaline Water ◽

New Energy ◽

Recent Developments ◽

Cell Components

Environmental issues make the quest for better and cleaner energy sources a priority. Worldwide, researchers and companies are continuously working on this matter, taking one of two approaches: either finding new energy sources or improving the efficiency of existing ones. Hydrogen is a well-known energy carrier due to its high energy content, but a somewhat elusive one for being a gas with low molecular weight. This review examines the current electrolysis processes for obtaining hydrogen, with an emphasis on alkaline water electrolysis. This process is far from being new, but research shows that there is still plenty of room for improvement. The efficiency of an electrolyzer mainly relates to the overpotential and resistances in the cell. This work shows that the path to better electrolyzer efficiency is through the optimization of the cell components and operating conditions. Following a brief introduction to the thermodynamics and kinetics of water electrolysis, the most recent developments on several parameters (e.g., electrocatalysts, electrolyte composition, separator, interelectrode distance) are highlighted.

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TiO 2 -NT electrodes modified with Ag and diamond like carbon (DLC) for hydrogen production by alkaline water electrolysis

Applied Surface Science ◽

10.1016/j.apsusc.2017.05.180 ◽

2017 ◽

Vol 420 ◽

pp. 416-428 ◽

Cited By ~ 4

Author(s):

Evrim Baran ◽

Zeynep Baz ◽

Ramazan Esen ◽

Birgül Yazici Devrim

Keyword(s):

Hydrogen Production ◽

Water Electrolysis ◽

Diamond Like Carbon ◽

Alkaline Water Electrolysis ◽

Alkaline Water

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Electrode Materials for Hydrogen Production by Alkaline-Water Electrolysis Powered by Renewable Energy Sources

10.1109/khpiweek53812.2021.9570062 ◽

2021 ◽

Author(s):

Antonina Maizelis ◽

Alexei Pilipenko

Keyword(s):

Renewable Energy ◽

Hydrogen Production ◽

Electrode Materials ◽

Renewable Energy Sources ◽

Water Electrolysis ◽

Energy Sources ◽

Alkaline Water Electrolysis ◽

Alkaline Water

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Analysis of Energy System in Norway with Focus on Energy Consumption Prediction

Management of Sustainable Development ◽

10.1515/msd-2017-0008 ◽

2017 ◽

Vol 9 (1) ◽

pp. 5-14 ◽

Cited By ~ 2

Author(s):

Maryam Hamlehdar ◽

Alireza Aslani

Keyword(s):

Energy Consumption ◽

Energy Demand ◽

Fossil Fuels ◽

Renewable Energy Sources ◽

Electricity Consumption ◽

Energy System ◽

High Energy ◽

Regression Result ◽

Industry Growth ◽

The Status

Abstract Today, the fossil fuels have dominant share of energy supply in order to respond to the high energy demand in the world. Norway is one of the countries with rich sources of fossil fuels and renewable energy sources. The current work is to investigate on the status of energy demand in Norway. First, energy and electricity consumption in various sectors, including industrial, residential are calculated. Then, energy demand in Norway is forecasted by using available tools. After that, the relationship between energy consumption in Norway with Basic economics parameters such as GDP, population and industry growth rate has determined by using linear regression model. Finally, the regression result shows a low correlation between variables.

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Development of an operation strategy for hydrogen production using solar PV energy based on fluid dynamic aspects

Open Engineering ◽

10.1515/eng-2017-0020 ◽

2017 ◽

Vol 7 (1) ◽

pp. 141-152 ◽

Cited By ~ 5

Author(s):

Ernesto Amores ◽

Jesús Rodríguez ◽

José Oviedo ◽

Antonio de Lucas-Consuegra

Keyword(s):

Hydrogen Production ◽

Fluid Dynamic ◽

Renewable Energy Sources ◽

Water Electrolysis ◽

Weather Conditions ◽

Energy Sources ◽

Electrolysis Cell ◽

Operation Strategy ◽

Solar Pv ◽

Alkaline Water Electrolysis

AbstractAlkaline water electrolysis powered by renewable energy sources is one of the most promising strategies for environmentally friendly hydrogen production. However, wind and solar energy sources are highly dependent on weather conditions. As a result, power fluctuations affect the electrolyzer and cause several negative effects. Considering these limiting effects which reduce the water electrolysis efficiency, a novel operation strategy is proposed in this study. It is based on pumping the electrolyte according to the current density supplied by a solar PV module, in order to achieve the suitable fluid dynamics conditions in an electrolysis cell. To this aim, a mathematical model including the influence of electrode-membrane distance, temperature and electrolyte flow rate has been developed and used as optimization tool. The obtained results confirm the convenience of the selected strategy, especially when the electrolyzer is powered by renewable energies.

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