Solvothermal and hydrothermal processes: the main physico-chemical factors involved and new trends

Demazeau, G.

doi:10.1007/s11164-011-0240-z

Cited by 44 publications

(25 citation statements)

References 136 publications

(117 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Thus chemical reactivity of a substance can be hugely modified under hydro‐/solvothermal conditions depending on the temperature and pressure conditions and percentage fill of the reactor. Majority of the hydro‐/solvothermal reactions reported in the literature are related to the synthesis of inorganic nanocrystals and are already reviewed in details in the literature . This review is intended to give an outlook on the low temperature hydro‐/solvothermal processing of graphene and of its related materials.…”

Section: Hydro‐/solvothermal Process: General Aspectsmentioning

confidence: 99%

Advances in Subcritical Hydro‐/Solvothermal Processing of Graphene Materials

2017

View full text Add to dashboard Cite

Many promising graphene-based materials are kept away from mainstream applications due to problems of scalability and environmental concerns in their processing. Hydro-/solvothermal techniques overwhelmingly satisfy both the aforementioned criteria, and have matured as alternatives to wet-chemical methods with advances made over the past few decades. The insolubility of graphene in many solvents poses considerable difficulties in their processing. In this context hydro-/solvothermal techniques present an ideal opportunity for processing of graphenic materials with their versatility in manipulating the physical and thermodynamic properties of the solvent. The flexibility in hydro-/solvothermal techniques for manipulation of solvent composition, temperature and pressure provides numerous handles to manipulate graphene-based materials during synthesis. This review provides a comprehensive look at the subcritical hydro-/solvothermal synthesis of graphene-based functional materials and their applications. Several key synthetic strategies governing the morphology and properties of the products such as temperature, pressure, and solvent effects are elaborated. Advances in the synthesis, doping, and functionalization of graphene in hydro-/solvothermal media are highlighted together with our perspectives in the field.

show abstract

Section: Hydro‐/solvothermal Process: General Aspectsmentioning

confidence: 99%

Advances in Subcritical Hydro‐/Solvothermal Processing of Graphene Materials

2017

View full text Add to dashboard Cite

show abstract

“…5 In 2003, Yamasaki 8 proposed how information obtained from the study of fundamental Earth principles can inspire the development of new technologies in order to establish a sustainable society. 9 The earliest reports on laboratory scale hydrothermal experiments date back to 1845. 8 Since then scien-tic research papers on the technological possibilities of the conversion of carbon dioxide under hydrothermal conditions are being published on a regular basis.…”

Section: (Feo) Rock + H 2 O / (Fe 2 O 3 ) Rock + Hmentioning

confidence: 99%

Hydrothermal conversion of carbon dioxide into formate with the aid of zerovalent iron: the potential of a two-step approach

et al. 2015

View full text Add to dashboard Cite

Our research focuses on the hydrothermal conversion of carbon dioxide into formate with the aid of zerovalent iron. Conventionally, a one-step approach is applied wherein both (I) the production of hydrogen gas, through the oxidation of zerovalent iron in an aqueous medium and (II) the conversion of carbon dioxide with this hydrogen gas into formate/formic acid, are performed under the same reaction conditions at a temperature of approximately 300 °C. Until now, the yields of formate/formic acid mentioned in the literature are, in the absence of a catalytic substance, low (13.5%). Recently, we developed a hydrothermal hydrogen gas production method based on the oxidation of zerovalent iron and performed under mild conditions (temperature of 160 °C). This synthesis method produces hydrogen gas with a high purity (>99 mol%) and a significant yield (approximately 80 mol%). These experimental results suggested that the optimal hydrothermal reaction conditions for the production of hydrogen gas and the conversion of carbon dioxide, are strongly different in case of applying zerovalent iron as the reducing agent. Therefore, this paper studies the potential of a two-step approach to enhance the carbon conversion yields. The first step is the production of hydrogen gas via the developed method at 160 °C. The second step is the conversion of carbon dioxide at higher temperatures (250-350 °C). This study reveals that the solubility of hydrogen gas into the aqueous solution is a key parameter in order to achieve a high amount of carbon conversion. Therefore, a high temperature, the degree of filling and the initial hydrogen gas amount are necessary to successfully perform the carbon dioxide conversion step with high carbon conversion yields. Applying these insights have led to the experimental observation that via a two-step approach the conversion of potassium hydrogen carbonate into potassium formate can be successfully performed with higher carbon conversion yields, up to 77.9 wt%, and a selectivity of at least 81% when applying a reaction temperature of 280 °C for 24 hours, a degree of filling with water of 50 vol% and an initial amount of hydrogen gas of 100 mmol.

show abstract

“…This route, despite the synthetic advantages that it gives (almost always a pure hexagonal phase 215,216 , with very narrow size distributions 215 and small diameters 215 ) to the particles, needs harmful precursors, a carefully controlled inert atmosphere and high temperature, making this synthetic route very hard to manage and prone to danger in the laboratory. C) Hydro-and solvo-thermal routes are very simple synthetic strategies that give generally high quality nanocrystals 10,36,211,[217][218][219][220][221] due to the high temperature and autogenous pressure that generates inside the autoclave container; however, 36,217,222,223 . Another drawback of this synthetic route lies in the long reaction kinetic (sometimes more than 24 hours are needed to complete one synthesis 220 ) needed to complete the formation of the materials.…”

Section: Methods Hosts Remarksmentioning

confidence: 99%

“…C) Hydro-and solvo-thermal routes are very simple synthetic strategies that give generally high quality nanocrystals 10,36,211,[217][218][219][220][221] due to the high temperature and autogenous pressure that generates inside the autoclave container; however, 36,217,222,223 . Another drawback of this synthetic route lies in the long reaction kinetic (sometimes more than 24 hours are needed to complete one synthesis 220 ) needed to complete the formation of the materials. D) Microwave-assisted synthesis uses homogeneous heating, which generates crystalline solids in few minutes and that gives the freedom for controlled morphology and size of the derived product through an accurate tuning of synthetic conditions.…”

Section: Methods Hosts Remarksmentioning

confidence: 99%

“…However, to date, solvo-thermal modeling of UCNPs nucleation and growth has not been thoroughly studied yet, due to the intrinsic difficulties given by the limited control over reaction conditions, lack of visual observation and the thermal inertia of the reactors and the different pressure/temperature conditions that are found in autoclaves as compared to the glassware-based syntheses. 220 The lack of detailed models for nano-sized UC materials under solvothermal conditions is giving an opportunity for a deeper study of the nucleation and growth of nano-sized NaYF 4 : Yb, Ln. It is known that preparation of such crystals, under solvothermal conditions, generally form micro or sub-micro sized systems 36,211,223 (see Figure 1.26).…”

Section: Methods Hosts Remarksmentioning

confidence: 99%

See 1 more Smart Citation

Rationale Design of Up-Converting Nanoparticles Towards Advanced Optical Applications

Guzzetta¹

View full text Add to dashboard Cite

 F.G. would like to thank the Generalitat Valenciana for the "Santiago Grisolía" Scholarship (GRISOLIA/2014/018) for funding the Ph.D. position that has permitted carry out the research.  F.G. would like to thank the Gonel-Balaguer Hermanos Foundation from the Universitat Jaume I and the COST Action MP 1202: Rational design of hybrid organic-inorganic interfaces (HINT) for the economical contributions as a scholarship and stipend, towards the short stay at the Université Pierre et Marie Curie in Paris that has permitted to promote high impact research partnerships between the Instituto de nanomaterials Avanzados (INAM-UJI), Química Inorgánica y Órganica department and UJI as institution and the former.  F.G. would like to thank the COST Action MP 1202: Rational design of hybrid organic-inorganic interfaces (HINT) for financing in form of scholarship the COST school "Bottom-up approaches of hybrid materials: preparation and design", held at the Jozef Stefan Institute, in Ljubljana, Slovenia, 26-28/05/2015. "The principles of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom. It is not an attempt to violate any laws; it is something, in principle, that can be done, but in practice it has not been done because we are too big." Richard P. Feynman (1959) A me stesso, per la forza che ho avuto a rialzarmi A mia moglie Ana Cecilia, che ha avuto la forza di aspettarmi Alla mia famiglia, che non ha mai smesso di aiutarmi This work (2014-2018) is dedicated to my family, which moral and sometimes financial support has been of great help in difficult moments, to my wife Ana that had the patience to wait for this day to happen and to me, who, after a long time of sacrifices and depression, finally realize this dream. It is also dedicated to all the people who encouraged me not to give up, starting from my thesis director, Beatriz Julián-López. This work, outcome of a three years journey in a wonderful part of Spain, has been carried out by me. However, as always, it could not be done without the help of people both in the private and in the working life that helped me growing both as a man and as a professional. Therefore, here there is a list of persons that I want to thank. First of all I want to thankequallymy family, dad (Salvatore), mum (Vincenza), brother (Giorgio), my wife (Ana Cecilia), and my thesis director, Beatriz Julián-López to have given me this opportunity and to have believed in me when no one would have bet a penny in my favor. Furthermore I want to thank my advisor to have helped me in understanding the academic world far better than I previously did and to have been present both in my academic and private life as a friend. Secondly I want to thank the Generalitat Valenciana, from which I have benefitted economically these three years through a Grisolía doctoral scholarship. I want to thank the personnel at the Servicio Central de Instrumentación Científica whose friendship and technical knowledge has helped me in achieving the amazing results presented...

show abstract

Solvothermal and hydrothermal processes: the main physico-chemical factors involved and new trends

Cited by 44 publications

References 136 publications

Advances in Subcritical Hydro‐/Solvothermal Processing of Graphene Materials

Advances in Subcritical Hydro‐/Solvothermal Processing of Graphene Materials

Hydrothermal conversion of carbon dioxide into formate with the aid of zerovalent iron: the potential of a two-step approach

Rationale Design of Up-Converting Nanoparticles Towards Advanced Optical Applications

Contact Info

Product

Resources

About