In connection with the development of hydrogen energy, special attention is currently being paid to the creation of highly efficient water electrolyzers, including electrolyzers with alkaline ...electrolyte. The main disadvantage of hydrogen production by water electrolysis is its high energy consumption. The present article shows that energy consumption can be reduced by changing of the electrodes and diaphragm layout. The phase inversion method used for the manufacture of polymer-based porous diaphragms for alkaline water electrolysers made it possible to create an electrode-diaphragm assembly, where elements of electrode-diaphragm assembly represent a single element. The comparative research of electrolysis cells with different electrode-diaphragm assemblies and cells of the traditional "zero gap" was carried out.
At present, hydrogen is increasingly being used in various industries. Moreover, among all technologies for producing hydrogen, the proportion of electrolytic hydrogen is constantly increasing. The ...most widely used technology is industrial water alkaline electrolysers of various capacities. In parallel, the direction associated with the development of high-pressure water alkaline electrolysers begins to develop. This paper considers the issue of creating and testing a high-pressure water alkaline electrolyser of coaxial configuration. Possible problems are considered during the operation of its components under high pressures, and ways to solve these problems. The proposed type of coaxial configuration and the changes made to the composition of the diaphragm material made it possible to reach a pressure of 100 bar.
We report the first search for dark sectors performed at the NA64 experiment employing a high energy muon beam and a missing energy-momentum technique. Muons from the M2 beamline at the CERN Super ...Proton Synchrotron with a momentum of 160 GeV / c are directed to an active target. The signal signature consists of a single scattered muon with momentum < 80 GeV / c in the final state, accompanied by missing energy, i.e., no detectable activity in the downstream calorimeters. For a total dataset of ( 1.98 ± 0.02 ) × 10 10 muons on target, no event is observed in the expected signal region. This allows us to set new limits on the remaining ( m Z ′ , g Z ′ ) parameter space of a new Z ′ ( L μ − L τ ) vector boson which could explain the muon ( g − 2 ) μ anomaly. Additionally, our study excludes part of the parameter space suggested by the thermal dark matter relic abundance. Our results pave the way to explore dark sectors and light dark matter with muon beams in a unique and complementary way to other experiments. Published by the American Physical Society 2024
The paper presents a new porous coating of electrodes for water electrolyzers with an alkaline electrolyte, as well as methods for its modification with catalysts for the reaction of hydrogen and ...oxygen evolution. The coating is formed from a suspension of nickel-cobalt powder in an electroplating bath for applying a nickel-cobalt coating and is characterized by an acicular structure and a developed specific surface. Nickel-cobalt powder is obtained by thermal decomposition of mixed nickel-cobalt formate in 1,4-butanediol, which is a modifying additive for nickel plating bath. The results of studies of new electrode materials by physicochemical and electrochemical methods are reported.
The article is devoted to the features of the alkaline water electrolyzers use in power plants with a hydrogen energy storage systems based on renewable energy sources. The technology of ...nickel–cobalt electrodes electrochemical formation according to a printed 2–dimensional sketch is proposed. A new technique for the synthesis of diaphragms with a zirconium hydroxide hydrogel as a hydrophilic filler is considered. The current–voltage characteristics of an electrolytic cell located inside outer containment shell, designed for pressures up to 160 atm, are investigated.
The purpose of this research paper is to describe the characteristics and electrochemical performances of a pressurized alkaline water electrolysis short stack (5-cells, 0.5 kW) operated at 80 °C, ...from atmospheric pressure up to 100 bars. Expanded grids of metallic nickel covered with specific porous catalytic structures have been used as working electrodes. A polysulfone-based diaphragm with a high ionic conductivity has been specifically designed for operation in pressurized alkaline water electrolysis cells. I–V polarization curves have been recorded at current densities up to 1000 mA/cm2, at temperatures up to 80 °C and under pressures up to 100 bars. The water electrolysis efficiency of this short-stack has been determined. A specific energy consumption of ca. 4.4–4.5 kWh/Nm3 has been obtained in the high current density range. Durability tests have been performed on the short stack over 1000 h. A limited degradation rate <5 μV/h has been recorded over that period of test.
•Expanded nickel grids with catalysts coatings were optimized for the HER and OER.•Thin porous polysulfone diaphragms containing TiO2 fillers were used as separator.•A 0.5 kW alkaline water electrolysis short-stack was developed and tested.•Current densities up to 1 A/cm2 and pressures up to 100 bars were achieved.
We propose the first
Se
arch for
D
ark
S
ector at the Brazilian Synchrotron Light Laboratory, site of Sirius, a fourth-generation storage ring. We show that UVX, Sirius predecessor, can be a ...promising dark sector detector,
SeDS
, with unprecedented sensitivity. The search is based on a
1
-
3
GeV positron beam impinging on a thick target leading the
e
+
e
-
→
γ
A
′
reaction, followed by a missing mass spectrum event reconstruction. We show that
SeDS
has the potential to probe dark photons with masses up to 55 MeV and kinetic coupling down to
ϵ
2
∼
10
-
12
. Therefore, such experiment would constitute the best dark photon probe worldwide in the
10
-
55
MeV mass range, being able to probe an unexplored region of parameter space.
We report the results of a search for a new vector boson (
A
′
) decaying into two dark matter particles
χ
1
χ
2
of different mass. The heavier
χ
2
particle subsequently decays to
χ
1
and an ...off-shell Dark Photon
A
′
∗
→
e
+
e
-
. For a sufficiently large mass splitting, this model can explain in terms of new physics the recently confirmed discrepancy observed in the muon anomalous magnetic moment at Fermilab. Remarkably, it also predicts the observed yield of thermal dark matter relic abundance. A detailed Monte-Carlo simulation was used to determine the signal yield and detection efficiency for this channel in the NA64 setup. The results were obtained re-analyzing the previous NA64 searches for an invisible decay
A
′
→
χ
χ
¯
and axion-like or pseudo-scalar particles
a
→
γ
γ
. With this method, we exclude a significant portion of the parameter space justifying the muon g-2 anomaly and being compatible with the observed dark matter relic density for
A
′
masses from 2
m
e
up to 390 MeV and mixing parameter
ε
between
3
×
10
-
5
and
2
×
10
-
2
.
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