scholarly journals Fabrication of Six Manganese Containing Polyoxometalate Modified Graphite C3N4 Nanosheets Catalysts Used to Catalyze Water Decomposition

Catalysts ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 856
Author(s):  
Yue Wu ◽  
Xiaoxia Yu ◽  
Zhijing Fu ◽  
Jianye Pei ◽  
Lihua Bi
Keyword(s):  
Composite Film ◽  
Composite Electrode ◽  
Low Cost ◽  
Structure Characteristic ◽  
Hydrogen Energy ◽  
High Electron ◽  
Human Beings ◽  
Water Decomposition ◽  
Assembly Technology ◽  
Decomposition Of Water

With the increase in gas population, the demand for clean and renewable energy is increasing. Hydrogen energy has a high combustion conversion energy while water is its combustion product. In recent years, a way to convert water into hydrogen and oxygen has been found by human beings inspired by plant photosynthesis. However, water decomposition consumes a significant amount of energy and is expensive. People expect to obtain a water decomposition catalyst with low cost and high efficiency. This work selected a six-manganese containing polyoxometalate with a similar structure characteristic to photosynthesizing PSII to fabricate with graphite C3N4 nanosheets for the construction of composite film (Mn6SiW/g-C3N4NSs) electrode via layer by layer self-assembly technology, which was used for the photo-electrochemical decomposition of water under visible light conditions. The binary composite film electrode displayed good catalytic efficiency. The photoelectric density of the composite electrode is 46 μA/cm2 (at 1.23 V vs. Ag/AgCl) and 239 μA/cm2 (at 1.5 V vs. Ag/AgCl). Compared with the g-C3N4NSs electrode alone, the photoelectric density of the composite electrode increased by 1 time. The reason is attributed to the fact that Mn6SiW has a similar structure characteristic to photosynthesizing PSII and high electron transferability. The construction of the composite film containing low-cost Mn6SiW to modify g-C3N4NSs can effectively improve the photocatalytic decomposition of water, thus this study provides valuable reference information for the development of low-cost and high-performance photo-electrocatalytic materials.

scholarly journals Photocatalytic Overall Water Splitting by SrTiO3 with Surface Oxygen Vacancies

Nanomaterials ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2572
Author(s):  
Yanfei Fan ◽  
Yan Liu ◽  
Hongyu Cui ◽  
Wen Wang ◽  
Qiaoyan Shang ◽  
...  
Keyword(s):  
Visible Light ◽  
Water Splitting ◽  
Oxygen Vacancies ◽  
Low Cost ◽  
Energy Levels ◽  
Light Response ◽  
Hydrogen Energy ◽  
Surface Oxygen ◽  
Carbon Reduction ◽  
Overall Water Splitting

Strontium Titanate has a typical perovskite structure with advantages of low cost and photochemical stability. However, the wide bandgap and rapid recombination of electrons and holes limited its application in photocatalysis. In this work, a SrTiO3 material with surface oxygen vacancies was synthesized via carbon reduction under a high temperature. It was successfully applied for photocatalytic overall water splitting to produce clean hydrogen energy under visible light irradiation without any sacrificial reagent for the first time. The photocatalytic overall water splitting ability of the as-prepared SrTiO3-C950 is attributed to the surface oxygen vacancies that can make suitable energy levels for visible light response, improving the separation and transfer efficiency of photogenerated carriers.

scholarly journals Engineering Mesoporous NiO with Enriched Electrophilic Ni3+ and O− toward Efficient Oxygen Evolution

Catalysts ◽  
2018 ◽  
Vol 8 (8) ◽  
pp. 310 ◽  
Author(s):  
Xiu Liu ◽  
Zhi-Yuan Zhai ◽  
Zhou Chen ◽  
Li-Zhong Zhang ◽  
Xiu-Feng Zhao ◽  
...  
Keyword(s):  
Surface Area ◽  
Oxygen Evolution ◽  
Low Cost ◽  
Large Surface Area ◽  
Nucleophilic Attack ◽  
Title Reaction ◽  
Highly Active ◽  
Decomposition Of Water ◽  
Uniform Mesopores

Tremendous efforts have been devoted to develop low-cost and highly active electrocatalysts for oxygen evolution reaction (OER). Here, we report the synthesis of mesoporous nickel oxide by the template method and its application in the title reaction. The as-prepared mesoporous NiO possesses a large surface area, uniform mesopores, and rich surface electrophilic Ni3+ and O− species. The overpotential of meso-NiO in alkaline medium is 132 mV at 10 mA cm−1 and 410 mV at 50 mA cm−1, which is much smaller than that of the other types of NiO samples. The improvement in the OER activity can be ascribed to the synergy of the large surface area and uniform mesopores for better mass transfer and high density of Ni3+ and O− species favoring the nucleophilic attack by OH− to form a NiOOH intermediate. The reaction process and the role of electrophilic Ni3+ and O− were discussed in detail. This results are more conducive to the electrochemical decomposition of water to produce hydrogen fuel as a clean and renewable energy.

scholarly journals Lead Oxide-Graphite Composite Electrode for pH Measurement

2015 ◽  
Vol 15 (1) ◽  
pp. 61-66
Author(s):  
Ranjan Nepal ◽  
Raja Ram Pradhananga
Keyword(s):  
Metal Ions ◽  
Lead Oxide ◽  
Composite Electrode ◽  
Low Cost ◽  
Potential Gradient ◽  
Ph Measurement ◽  
Indicator Electrode ◽  
Quick Response ◽  
Acid Base ◽  
Graphite Composite

Lead oxide-graphite composite electrode for pH measurement had been fabricated with different percentage of PbO2 in the composite. The proportions of lead oxide affected the sensitivity of the electrode. The electrode composed of 50% lead oxide and 50% graphite gave reproducible result and behaved in Nernstian manner with a potential gradient of -58.8±0.3 mV per unit change in pH. Metal ions such as iron (II), iron (III) and lead (II) interfered in the measurement of pH, while silver (I), copper (II), oxidizing agents such as dichromate and permanganate do not interfere. In absence of interfering ion, the lead oxide-graphite composite electrode could be used for the measurement of pH from 2 to 11. This electrode can also be used as an indicator electrode for acid base titrations. Low cost, quick response, easy to fabricate are some of the advantages of the lead oxide-graphite composite electrode. This electrode is also found to be sensitive to Pb2+ -ions and can be used as a Pb2+-ion sensor up to 10-4M.DOI: http://dx.doi.org/10.3126/njst.v15i1.12015  Nepal Journal of Science and TechnologyVol. 15, No.1 (2014) 61-66

scholarly journals Electrodeposition of Iridium-Nickel Thin Films on Copper Foam: Effects of Loading and Solution Temperature on HER Performance of Electrocatalyst in Alkaline Water

2020 ◽  
Author(s):  
Jianwen Liu ◽  
Wangping Wu ◽  
Xiang Wang
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Hydrogen Evolution ◽  
Electrocatalytic Activity ◽  
Electrochemical Impedance ◽  
Low Cost ◽  
Solution Temperature ◽  
High Deposition Rate ◽  
Hydrogen Energy ◽  
Copper Foam

Developing novel hydrogen evolution reaction (HER) catalysts with high activity, high stability and low cost is of great importance for the applications of hydrogen energy. In this work, iridium-nickel (Ir-Ni) thin films were electrodeposited on a copper foam as electrocatalyst for HER, and electrodeposition mechanism of Ir-Ni film was studied. The morphology and chemical composition of thin films were determined by scanning electron microscopy and energy-dispersive spectroscopy, respectively. The electrocatalytic performances of the films were estimated by linear sweep voltammograms, electrochemical impedance spectroscopy and cyclic voltammetry. The results show that Ir-Ni thin films were attached to the substrate of porous structure and hollow topography. The deposition of Ni was preferable in the electrolyte without the addition of additives, and Ir-Ni thin film was alloyed, resulting in high deposition rate for Ir42Ni58 thin film, and subsequently an increase of Ir content in the thin films of Ir80Ni20 and Ir88Ni12. Ir-Ni thin films with Tafel slopes of 40-49 mV·dec-1 exhibited highly efficient electrocatalytic activity for HER. The electrocatalytic activity of Ir-Ni thin films showed a loading dependence. As the solution temperature raised from 20 oC to 60 oC, the hydrogen evolution performance of Ir-Ni thin films improved. The apparent activation energy value of Ir88Ni12 film was 7.1 kJ·mol-1. Long-term hydrogen evolution tests exhibited excellent electrocatalystic stability in alkaline solution.

scholarly journals Preparation of Cerium Oxide-MWCNTs Nanocomposite Bulk Modified Carbon Ceramic Electrode: A Sensitive Sensor for Tamoxifen Determination in Human Serum Samples

2021 ◽  
Author(s):  
Sepideh Shafaei ◽  
Elyas Hosseinzadeh ◽  
Gulsah Saydan Kanberoglu ◽  
Balal Khalilzadeh ◽  
Rahim Mohammad-Rezaei
Keyword(s):  
Cerium Oxide ◽  
Limit Of Detection ◽  
Low Cost ◽  
High Electron ◽  
Range Limit ◽  
Serum Samples ◽  
Important Species ◽  
Carbon Ceramic Electrode ◽  
Carbon Ceramic

Abstract In this study, cerium oxide and multi-walled carbon nanotubes nanocomposite was incorporated into the carbon ceramic electrode (CeO2-MWCNTs/CCE) as a renewable electrode for the electrocatalytic purposes. To demonstrate capability of the fabricated electrode, determination of Tamoxifen as an important anticancer drug with differential pulse voltammetry technique was evaluated. Linear range, limit of detection and sensitivity of the developed sensor were found to be 0.2-40 nM, 0.132 nM and 1.478 µA nM-1 cm-2, respectively. Ease of production, low cost and high electron transfer rate of CeO2-MWCNTs/CCE promise it as a novel electro-analytical tool for determination of important species in real samples.

Design Strategy of Tightening Spindle System on the Principle of Modularity

2011 ◽  
Vol 141 ◽  
pp. 39-42
Author(s):  
Ya Wei Zhang ◽  
Jian Guo Yang
Keyword(s):  
Modular Design ◽  
Low Cost ◽  
Design Strategy ◽  
Torque Control ◽  
Spindle System ◽  
Assembly Technology ◽  
Bolt Connection ◽  
Module Partition ◽  
Standard Components

Modern and reliable tightening spindle systems are indispensable due to importance of bolt connection in assembly technology, and the tightening spindle system is developed in order that automated tightening processes is able to ensure uniform quality of the tightened bolt connection. In this paper, the strategy “torque control and angle checked” of tightening is discussed and analyzed on the basis that the process mechanism of forming bolt connection is clarified. This strategy builds the base and boundary conditions of modular design strategy for tightening spindle system which is introduced, because it makes design flexibly, and many standard components can be chosen with more efficiency and low cost. The module partition bases on the function of the components of the system. The possibility of expansion of the tightening system comes into discussion too.

Low cost stretchable carbon graphite composite electrode

2020 ◽  
Vol 26 (4) ◽  
pp. 126-132
Author(s):  
Su-Yong Nam ◽  
Shinyoung Kim ◽  
Se-Hoon Park ◽  
Hyun Jin Nam
Keyword(s):  
Composite Electrode ◽  
Low Cost ◽  
Graphite Composite

EFFICIENCY INVESTIGATION OF THE WAYS OF COMBINING NPP WITH A HYDROGEN COMPLEX FOR THE PURPOSE OF SALE OF HYDROGEN AND GENERATION OF ADDITIONAL ELECTRIC POWER

2020 ◽  
pp. 19-29
Author(s):  
V.E. Yurin ◽  
◽  
A.N. Egorov ◽  
D.O. Bashlykov ◽  
A.B. Moskalenko ◽  
...  
Keyword(s):  
Economic Efficiency ◽  
Low Cost ◽  
Energy System ◽  
Operating Conditions ◽  
Hydrogen Energy ◽  
Utilization Factor ◽  
Energy Complex ◽  
Load Schedule ◽  
Installed Capacity ◽  
Maximum Utilization

With an increase in the share of NPPs in the energy system, it becomes necessary for them to participate in the regulation of the electric load schedule. At the same time, the operation of the NPP with the maximum utilization factor of the installed capacity of the reactor was economically and technically justified. One of the promising ways to solve this problem is to install consumers-regulators at NPPs. The hydrogen energy complex can be effectively used as a consumer-regulator. The authors have previously developed an autonomous hydrogen energy generating complex, scientifically substantiated its economic efficiency. As the study has shown, the economic efficiency of an autonomous hydrogen energy complex directly depends on the sale tariffs for electricity. The low cost of electricity sold leads to a deterioration in economic indicators, up to a lack of recoupment. In this regard, as an alternative option, this work considers the possibility of selling hydrogen and oxygen as a commercial product at existing prices. A comparative study for a range of electricity tariffs and prices for hydrogen and oxygen was carried out on the basis of the methodology presented earlier by the authors, which makes it possible to study ways to improve NPPs on the basis of a comprehensive analysis of economic efficiency, safety and system effects achieved during the installation of new and modernization of existed equipment. The results obtained make it possible to choose the type of hydrogen energy complex depending on the operating conditions for the selected region of operation.

Sustainable hydrogen energy

2007 ◽  
Author(s):  
Peter P. Edwards ◽  
Vladimir L. Kuznetsov
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Energy Supply ◽  
Fossil Fuel ◽  
Low Cost ◽  
Hydrogen Energy ◽  
The Future ◽  
Energy Economy ◽  
Fossil Fuel Energy ◽  
Carbon Based

Hydrogen is the simplest and most abundant chemical element in our universe— it is the power source that fuels the Sun and its oxide forms the oceans that cover three quarters of our planet. This ubiquitous element could be part of our urgent quest for a cleaner, greener future. Hydrogen, in association with fuel cells, is widely considered to be pivotal to our world’s energy requirements for the twenty-first century and it could potentially redefine the future global energy economy by replacing a carbon-based fossil fuel energy economy. The principal drivers behind the sustainable hydrogen energy vision are therefore: • the urgent need for a reduction in global carbon dioxide emissions; • the improvement of urban (local) air quality; • the abiding concerns about the long-term viability of fossil fuel resources and the security of our energy supply; • the creation of a new industrial and technological energy base—a base for innovation in the science and technology of a hydrogen/fuel cell energy landscape. The ultimate realization of a hydrogen-based economy could confer enormous environmental and economic benefits, together with enhanced security of energy supply. However, the transition from a carbon-based(fossil fuel) energy system to a hydrogen-based economy involves significant scientific, technological, and socio-economic barriers. These include: • low-carbon hydrogen production from clean or renewable sources; • low-cost hydrogen storage; • low-cost fuel cells; • large-scale supporting infrastructure, and • perceived safety problems. In the present chapter we outline the basis of the growing worldwide interest in hydrogen energy and examine some of the important issues relating to the future development of hydrogen as an energy vector. As a ‘snapshot’ of international activity, we note, for example, that Japan regards the development and dissemination of fuel cells and hydrogen technologies as essential: the Ministry of Economy and Industry (METI) has set numerical targets of 5 million fuel cell vehicles and10 million kW for the total power generation by stationary fuel cells by 2020. To meet these targets, METI has allocated an annual budget of some £150 million over four years.

scholarly journals A SOLID Fe2O3-GRAPHITE COMPOSITE ELECTRODE FOR pH MEASUREMENT

2015 ◽  
Vol 12 (12) ◽  
pp. 44-47
Author(s):  
Suchi Srivastava ◽  
Raja Ram Pradhananga
Keyword(s):  
Electrode Potential ◽  
Composite Electrode ◽  
Low Cost ◽  
Ph Sensor ◽  
Potential Gradient ◽  
Graphite Composite ◽  
Ph Response ◽  
Potentiometric Response ◽  
Unit Change ◽  
Oxidized Graphite

A solid Fe2O3-graphite composite electrode was prepared and investigated for use as a potentiometric pH sensor. The electrode was constructed by mixing iron (III) oxide, oxidized graphite and wax that was put over silver disc onto a polypropylene rod. The response of the electrode was investigated by measuring electrode potential as a function of pH.The effect of composition of the electrode material (Fe2O3 and oxidized graphite ration) on the electrode response was investigated. The electrode with 40% Fe2O3, 30% graphite and 30% wax by mass was found to give the best potentiometric response. This electrode behaves in Nernstian manner with a potentiometric gradient of 56.6±0.4 mV per unit change in pH at 25?C within the working range of pH 2-9.The electrode was also used for the end-point detection in potentiometric acid-base titrations and found to be an excellent electrode for pH-metric titration. The effect of oxidation of electrode on pH response was investigated by dipping electrode in 0.1N KMnO4, 1:1HNO3 and 0.1N Ce4+ solutions for different interval of time. This treatment of the electrode with oxidizing agents increased the standard electrode potential of the electrode however potential gradient per unit change in pH remains unaltered. Low cost, quick response and easy to prepare are the advantages of the iron oxide - graphite composite electrode as a pH sensor. However some metal ions and oxidising agents interfered in the determination of pH using this electrode which is the limitation of using these electrodes.Scientific World, Vol. 12, No. 12, September 2014, page 44-47

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