scispace - formally typeset
Search or ask a question
Topic

Hydrothermal synthesis

About: Hydrothermal synthesis is a research topic. Over the lifetime, 13241 publications have been published within this topic receiving 316314 citations.


Papers
More filters
Journal ArticleDOI
TL;DR: The microspheres thus obtained possess a core-shell structure consisting of a highly aromatic nucleus (hydrophobic) and a hydrophilic shell containing a high concentration of reactive oxygen functional groups (i.e., hydroxyl/phenolic, carbonyl, or carboxylic).
Abstract: Carbon-rich-quick scheme: A carbon-rich solid product made up of uniform micrometer-sized spheres of tunable diameter has been synthesized by the hydrothermal carbonization of saccharides. These microspheres possess a core-shell chemical structure based on the different nature of the oxygen functionalities between the core and the outer layer (see figure).A carbon-rich solid product, here denoted as hydrochar, has been synthesized by the hydrothermal carbonization of three different saccharides (glucose, sucrose, and starch) at temperatures ranging from 170 to 240 degrees C. This material is made up of uniform spherical micrometer-sized particles that have a diameter in the 0.4-6 mum range, which can be modulated by modifying the synthesis conditions (i.e., the concentration of the aqueous saccharide solution, the temperature of the hydrothermal treatment, the reaction time, and type of saccharide). The formation of the carbon-rich solid through the hydrothermal carbonization of saccharides is the consequence of dehydration, condensation, or polymerization and aromatization reactions. The microspheres thus obtained possess, from a chemical point of view, a core-shell structure consisting of a highly aromatic nucleus (hydrophobic) and a hydrophilic shell containing a high concentration of reactive oxygen functional groups (i.e., hydroxyl/phenolic, carbonyl, or carboxylic).

1,194 citations

Journal ArticleDOI
Xun Wang1, Yadong Li1
TL;DR: In this article, a selective control hydrothermal method has been developed in the preparation of α- and β-MnO2 single-crystal nanowires, which can be influenced by the concentration of NH4+ and SO42-.
Abstract: A selective-control hydrothermal method has been developed in the preparation of α- and β-MnO2 single-crystal nanowires. The crystal structure and morphology of the final products can be influenced by the concentration of NH4+ and SO42-.

978 citations

Journal ArticleDOI
TL;DR: Interestingly, SEM, TEM, and HRTEM revealed a variety of structures ranging from nanostructured surface with a distinct platelike morphology to nanorod depending upon the hydrothermal reaction time employed during the preparation of the manganese oxide: increasing the amount of individual nanorods in the materials prepared with longer hydrother mal reaction time.
Abstract: The effect of varying the hydrothermal time to synthesize manganese oxide (MnO(2)) nanostructures was investigated along with their influence on structural, morphological, compositional, and electrochemical properties in supercapacitor electrode materials. XRD and TEM studies showed that the MnO(2) prepared in shorter hydrothermal dwell time was a mixture of amorphous and nanocrystalline particles, and there was an evolution of crystallinity of the nanostructures as the dwell time increased from 1 to 18 h. Interestingly, SEM, TEM, and HRTEM revealed a variety of structures ranging from nanostructured surface with a distinct platelike morphology to nanorods depending upon the hydrothermal reaction time employed during the preparation of the manganese oxide: increasing the amount of individual nanorods in the materials prepared with longer hydrothermal reaction time. The surface area of the synthesized nanomaterials varied from 100 to 150 m(2)/g. Electrochemical properties were evaluated using cyclic voltammetry (CV) and galvanostatic charge-discharge studies, and the capacitance values were in the range 72-168 F/g depending upon synthesis conditions. The formation mechanism of the nanorods and their impact on the specific capacitance were discussed in detail.

871 citations

Journal ArticleDOI
TL;DR: In this paper, the photocatalytic performance of the reduced graphene oxide (hGO)-TNT composites was evaluated for the photodegradation of malachite green using X-ray diffraction (XRD), Raman, FTIR, and XPS analysis.
Abstract: In this study, TiO2 nanotube (TNT)/reduced graphene oxide (hGO) composites were prepared by an alkaline hydrothermal process. This was achieved by decorating graphene oxide (GO) layers with commercially available TiO2 nanoparticles (P90) followed by hydrothermal synthesis, which converts the TiO2 nanoparticles to small diameter (∼9 nm) TNTs on the hGO surface. The alkaline medium used to synthesize the TNTs simultaneously converts GO to deoxygenated graphene oxide (hGO). Compared to GO, the hGO has a ∼70% reduction of oxygenated species after alkaline hydrothermal treatment. The graphene nature of hGO in the composites was confirmed by X-ray diffraction (XRD), Raman, FTIR, and X-ray photoelectron spectroscopy (XPS) analysis. The photocatalytic performance of the hGO-TNT composites was evaluated for the photodegradation of malachite green. It was found that the ratio of hGO to TNT in the composites significantly affects the photocatalytic activity. Higher amounts of hGO in hGO-TNT composites showed lower p...

868 citations

Journal ArticleDOI
TL;DR: The importance of hydrothermal technology in the preparation of nanomaterials has been discussed in detail with reference to the processing of advanced materials for nanotechnology as discussed by the authors, and the role of supercritical water and supercritical fluids is discussed with appropriate examples.

830 citations


Network Information
Related Topics (5)
Oxide
213.4K papers, 3.6M citations
91% related
Nanoparticle
85.9K papers, 2.6M citations
88% related
Raman spectroscopy
122.6K papers, 2.8M citations
88% related
Catalysis
400.9K papers, 8.7M citations
87% related
Carbon nanotube
109K papers, 3.6M citations
87% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
2023217
2022464
2021479
2020599
2019658
2018629