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Hydrazine

About: Hydrazine is a(n) research topic. Over the lifetime, 11059 publication(s) have been published within this topic receiving 121281 citation(s). The topic is also known as: diazane & tetrahydridodinitrogen.
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Journal ArticleDOI
Abstract: The preparation of solution-processable graphene from graphite oxide typically involves a hydrazine reduction step, but the use of such a reagent in the large-scale implementation of this approach is not desirable due to its high toxicity. Here, we compare the deoxygenation efficiency of graphene oxide suspensions by different reductants (sodium borohydride, pyrogallol, and vitamin C, in addition to hydrazine), as well as by heating the suspensions under alkaline conditions. In almost all cases, the degree of reduction attainable and the subsequent restoration of relevant properties (e.g., electrical conductivity) lag significantly behind those achieved with hydrazine. Only vitamin C is found to yield highly reduced suspensions in a way comparable to those provided by hydrazine. Stable suspensions of vitamin C-reduced graphene oxide can be prepared not only in water but also in common organic solvents, such as N,N-dimethylformamide (DMF) or N-methyl-2-pyrrolidone (NMP). These results open the perspective ...

1,119 citations


Journal ArticleDOI
Xingfa Gao1, Joonkyung Jang1, Shigeru Nagase1Institutions (1)
Abstract: The density functional theory method (M05-2X/6-31G(d)) was used to investigate reaction mechanisms for deoxygenation of graphene oxides (GOs) with hydrazine or heat treatment. Three mechanisms were identified as reducing epoxide groups of GO with hydrazine as a reducing agent. No reaction path was found for the hydrazine-mediated reductions of the hydroxyl, carbonyl, and carboxyl groups of GO. We instead discovered the mechanisms for dehydroxylation, decarbonylation, and decarboxylation using heat treatment. The hydrazine de-epoxidation and thermal dehydroxylation of GO have opposite dependencies on the reaction temperature. In both reduction types, the oxygen functionalities attached to the interior of an aromatic domain in GO are removed more easily, both kinetically and thermodynamically, than those attached at the edges of an aromatic domain. The hydrazine-mediated reductions of epoxide groups at the edges are suspended by forming hydrazino alcohols. We provide atomic-level elucidation for the deoxyge...

922 citations


Journal ArticleDOI

638 citations


Journal ArticleDOI
01 Mar 1967-Water Research
Abstract: An automated procedure for the simultaneous determinations of nitrate and nitrite in water is presented. Nitrite initially present in the sample is determined by a conventional diazotization-coupling reaction. Nitrate in another portion of sample is quantitatively reduced with hydrazine sulfate to nitrite which is then determined by the same diazotization-coupling reaction. Subtracting the nitrite initially present in the sample from that after reduction yields nitrite equivalent to nitrate initially in the sample. The rate of analysis is 20 samples/hr. Applicable range of the described method is 0.05–10 mg/l nitrite or nitrate nitrogen; however, increased sensitivity can be obtained by suitable modifications.

616 citations


Journal ArticleDOI
Mahendra Yadav1, Qiang Xu1Institutions (1)
Abstract: In the search for future energy supplies, the application of hydrogen as an energy carrier is seen as a prospective issue. However, the implementation of a hydrogen economy is suffering from several unsolved problems. Particularly challenging is the storage of appropriate amounts of hydrogen. In this context one of the promising hydrogen storage techniques relies on liquid-phase chemical hydrogen storage materials, in particular, aqueous sodium borohydride, ammonia borane, hydrazine, hydrazine borane and formic acid. The use of these materials in hydrogen storage provides high gravimetric and volumetric hydrogen densities, low potential risk, and low capital investment because it is largely compatible with the current transport infrastructure. In this review, we survey the research progresses in hydrogen generation from these liquid-phase chemical hydrogen storage materials and their regeneration.

607 citations


Performance
Metrics
No. of papers in the topic in previous years
YearPapers
20225
2021225
2020259
2019330
2018352
2017343

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Topic's top 5 most impactful authors

N. V. Russavskaya

34 papers, 187 citations

V. A. Grabel’nykh

20 papers, 111 citations

A. I. Albanov

15 papers, 77 citations

Qiang Xu

13 papers, 1.5K citations

Zhang-Hui Lu

12 papers, 461 citations