Carbonyl-Iron Electrodes for Rechargeable-Iron Batteries

2015 ◽  
Vol 1 (1) ◽  
Author(s):  
A. Sundar Rajan ◽  
M. K. Ravikumar ◽  
K. R. Priolkar ◽  
S. Sampath ◽  
A. K. Shukla

AbstractNickel-iron and iron-air batteries are attractive for large-scale-electrical-energy storage because iron is abundant, low-cost and non-toxic. However, these batteries suffer from poor charge acceptance due to hydrogen evolution during charging. In this study, we have demonstrated iron electrodes prepared from carbonyl iron powder (CIP) that are capable of delivering a specific discharge capacity of about 400 mAh g−1 at a current density of 100 mA g−1 with a faradaic efficiency of about 80%. The specific capacity of the electrodes increases gradually during formation cycles and reaches a maximum in the 180th cycle. The slow increase in the specific capacity is attributed to the low surface area and limited porosity of the pristine CIP. Evolution of charge potential profiles is investigated to understand the extent of charge acceptance during formation cycles. In situ XRD pattern for the electrodes subsequent to 300 charge/discharge cycles confirms the presence of Fe with Fe(OH)2 as dominant phase.

2019 ◽  
Vol 116 (48) ◽  
pp. 23915-23922 ◽  
Author(s):  
Yongtao Meng ◽  
Xiao Zhang ◽  
Wei-Hsuan Hung ◽  
Junkai He ◽  
Yi-Sheng Tsai ◽  
...  

Electrochemical reduction of CO2 to useful chemicals has been actively pursued for closing the carbon cycle and preventing further deterioration of the environment/climate. Since CO2 reduction reaction (CO2RR) at a cathode is always paired with the oxygen evolution reaction (OER) at an anode, the overall efficiency of electrical energy to chemical fuel conversion must consider the large energy barrier and sluggish kinetics of OER, especially in widely used electrolytes, such as the pH-neutral CO2-saturated 0.5 M KHCO3. OER in such electrolytes mostly relies on noble metal (Ir- and Ru-based) electrocatalysts in the anode. Here, we discover that by anodizing a metallic Ni–Fe composite foam under a harsh condition (in a low-concentration 0.1 M KHCO3 solution at 85 °C under a high-current ∼250 mA/cm2), OER on the NiFe foam is accompanied by anodic etching, and the surface layer evolves into a nickel–iron hydroxide carbonate (NiFe-HC) material composed of porous, poorly crystalline flakes of flower-like NiFe layer-double hydroxide (LDH) intercalated with carbonate anions. The resulting NiFe-HC electrode in CO2-saturated 0.5 M KHCO3 exhibited OER activity superior to IrO2, with an overpotential of 450 and 590 mV to reach 10 and 250 mA/cm2, respectively, and high stability for >120 h without decay. We paired NiFe-HC with a CO2RR catalyst of cobalt phthalocyanine/carbon nanotube (CoPc/CNT) in a CO2 electrolyzer, achieving selective cathodic conversion of CO2 to CO with >97% Faradaic efficiency and simultaneous anodic water oxidation to O2. The device showed a low cell voltage of 2.13 V and high electricity-to-chemical fuel efficiency of 59% at a current density of 10 mA/cm2.


2015 ◽  
Vol 3 (37) ◽  
pp. 19011-19017 ◽  
Author(s):  
Boyang Ruan ◽  
Jun Wang ◽  
Dongqi Shi ◽  
Yanfei Xu ◽  
Shulei Chou ◽  
...  

Sodium-ion batteries (SIBs) have been attracting intensive attention at present as the most promising alternative to lithium-ion batteries in large-scale electrical energy storage applications, due to the low-cost and natural abundance of sodium.


2021 ◽  
Author(s):  
Madison R Tuttle ◽  
Christopher Walter ◽  
Emma Brackman ◽  
Curtis Moore ◽  
Matthew Espe ◽  
...  

Aqueous zinc-ion batteries (AZIBs) are promising candidates for large-scale electrical energy storage due to the inexpensive, safe, and non-toxic nature of zinc. One key area that requires further development is...


2021 ◽  
Author(s):  
Zhengyang Cai ◽  
Ping Wang ◽  
Ya Yan ◽  
Jiangwei Zhang ◽  
Xianying Wang

Abstract Nickel-iron based layered double hydroxides (NiFe LDH) have attracted tremendous research and industrial interests for oxygen evolution reaction electrocatalysis (OER). However, methodologies on simultaneous multi-regulations remain scarce. Herein, we report a versatile polyoxometallic acids (POMs) etching approach for ingeniously designing NiFe LDH, including morphological nanolayers tailoring, reconfiguration of Fe3+ and α-Ni(OH)2 active species, creating multiple vacancies of Ni, Fe and O and manufacturing interlayered POM polyanionic clusters as surface kinetic accelerators. Our experimental and theoretical data reveal that the key influencing factors are simultaneously controlled, resulting in synergistical enhancement with electrocatalytic OER activity of η10 = 206 mV, stability (negligible change of η500 for 24 h), and turnover frequency value (TOFFe, mol) of 2.03 s− 1. To elucidate the evolution, we derive an empirical formula to quantitatively identifying the key performance-determining factors, coinciding with the work and most of literature data. The expression offers an opportunity for first and fast reliability on materials screening. Moreover, the electrocatalyst is further produced on a large scale with low cost and high performance, demonstrating its feasibility of promising configuration of NiFe LDH-PMo12(+) ‖ Ni@NiFe LDH(-) for practical anion-exchange membrane (AEM)-electrode-stack cells water electrolysis.


Batteries ◽  
2018 ◽  
Vol 5 (1) ◽  
pp. 1 ◽  
Author(s):  
Alagar Paulraj ◽  
Yohannes Kiros ◽  
Mylad Chamoun ◽  
Henrik Svengren ◽  
Dag Noréus ◽  
...  

Fe-air or Ni-Fe cells can offer low-cost and large-scale sustainable energy storage. At present, they are limited by low coulombic efficiency, low active material use, and poor rate capability. To overcome these challenges, two types of nanostructured doped iron materials were investigated: (1) copper and tin doped iron (CuSn); and (2) tin doped iron (Sn). Single-wall carbon nanotube (SWCNT) was added to the electrode and LiOH to the electrolyte. In the 2 wt. % Cu + 2 wt. % Sn sample, the addition of SWCNT increased the discharge capacity from 430 to 475 mAh g−1, and charge efficiency increased from 83% to 93.5%. With the addition of both SWCNT and LiOH, the charge efficiency and discharge capacity improved to 91% and 603 mAh g−1, respectively. Meanwhile, the 4 wt. % Sn substituted sample performance is not on par with the 2 wt. % Cu + 2 wt. % Sn sample. The dopant elements (Cu and Sn) and additives (SWCNT and LiOH) have a major impact on the electrode performance. To understand the relation between hydrogen evolution and charge current density, we have used in operando charging measurements combined with mass spectrometry to quantify the evolved hydrogen. The electrodes that were subjected to prolonged overcharge upon hydrogen evolution failed rapidly. This insight could help in the development of better charging schemes for the iron electrodes.


2016 ◽  
Vol 4 (19) ◽  
pp. 7207-7213 ◽  
Author(s):  
Sangmin Park ◽  
Baskar SenthilKumar ◽  
Kyoungho Kim ◽  
Soo Min Hwang ◽  
Youngsik Kim

Cheap, familiar saltwater (NaCl solution) was utilized to build low-cost, safe rechargeable batteries for large-scale electrical energy storage applications.


1987 ◽  
Vol 19 (5-6) ◽  
pp. 701-710 ◽  
Author(s):  
B. L. Reidy ◽  
G. W. Samson

A low-cost wastewater disposal system was commissioned in 1959 to treat domestic and industrial wastewaters generated in the Latrobe River valley in the province of Gippsland, within the State of Victoria, Australia (Figure 1). The Latrobe Valley is the centre for large-scale generation of electricity and for the production of pulp and paper. In addition other industries have utilized the brown coal resource of the region e.g. gasification process and char production. Consequently, industrial wastewaters have been dominant in the disposal system for the past twenty-five years. The mixed industrial-domestic wastewaters were to be transported some eighty kilometres to be treated and disposed of by irrigation to land. Several important lessons have been learnt during twenty-five years of operating this system. Firstly the composition of the mixed waste stream has varied significantly with the passage of time and the development of the industrial base in the Valley, so that what was appropriate treatment in 1959 is not necessarily acceptable in 1985. Secondly the magnitude of adverse environmental impacts engendered by this low-cost disposal procedure was not imagined when the proposal was implemented. As a consequence, clean-up procedures which could remedy the adverse effects of twenty-five years of impact are likely to be costly. The question then may be asked - when the total costs including rehabilitation are considered, is there really a low-cost solution for environmentally safe disposal of complex wastewater streams?


BMC Biology ◽  
2019 ◽  
Vol 17 (1) ◽  
Author(s):  
Amrita Srivathsan ◽  
Emily Hartop ◽  
Jayanthi Puniamoorthy ◽  
Wan Ting Lee ◽  
Sujatha Narayanan Kutty ◽  
...  

Abstract Background More than 80% of all animal species remain unknown to science. Most of these species live in the tropics and belong to animal taxa that combine small body size with high specimen abundance and large species richness. For such clades, using morphology for species discovery is slow because large numbers of specimens must be sorted based on detailed microscopic investigations. Fortunately, species discovery could be greatly accelerated if DNA sequences could be used for sorting specimens to species. Morphological verification of such “molecular operational taxonomic units” (mOTUs) could then be based on dissection of a small subset of specimens. However, this approach requires cost-effective and low-tech DNA barcoding techniques because well-equipped, well-funded molecular laboratories are not readily available in many biodiverse countries. Results We here document how MinION sequencing can be used for large-scale species discovery in a specimen- and species-rich taxon like the hyperdiverse fly family Phoridae (Diptera). We sequenced 7059 specimens collected in a single Malaise trap in Kibale National Park, Uganda, over the short period of 8 weeks. We discovered > 650 species which exceeds the number of phorid species currently described for the entire Afrotropical region. The barcodes were obtained using an improved low-cost MinION pipeline that increased the barcoding capacity sevenfold from 500 to 3500 barcodes per flowcell. This was achieved by adopting 1D sequencing, resequencing weak amplicons on a used flowcell, and improving demultiplexing. Comparison with Illumina data revealed that the MinION barcodes were very accurate (99.99% accuracy, 0.46% Ns) and thus yielded very similar species units (match ratio 0.991). Morphological examination of 100 mOTUs also confirmed good congruence with morphology (93% of mOTUs; > 99% of specimens) and revealed that 90% of the putative species belong to the neglected, megadiverse genus Megaselia. We demonstrate for one Megaselia species how the molecular data can guide the description of a new species (Megaselia sepsioides sp. nov.). Conclusions We document that one field site in Africa can be home to an estimated 1000 species of phorids and speculate that the Afrotropical diversity could exceed 200,000 species. We furthermore conclude that low-cost MinION sequencers are very suitable for reliable, rapid, and large-scale species discovery in hyperdiverse taxa. MinION sequencing could quickly reveal the extent of the unknown diversity and is especially suitable for biodiverse countries with limited access to capital-intensive sequencing facilities.


2021 ◽  
Author(s):  
Mirai Ohara ◽  
A. Shahul Hameed ◽  
Kei Kubota ◽  
Akihiro Katogi ◽  
Kuniko Chihara ◽  
...  

K-ion batteries (KIBs) are promising for large-scale electrical energy storage owing to the abundant resources and the electrochemical specificity of potassium. Among the positive electrode materials for KIBs, vanadium-based polyanionic...


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