Formation of a Dimeric Precursor Intermediate during the Nonaqueous Synthesis of Titanium Dioxide Nanocrystals

Zimmermann, Mandy; Ibrom, Kerstin; Jones, Peter G.; Garnweitner, Georg

doi:10.1002/cnma.201600264

Cited by 8 publications

(9 citation statements)

References 64 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Phenomena of formation leading to binary and doped metal oxide nanoparticles were described in several papers ( [29,30] and [31,32], respectively). The mechanisms of secondary particle formation during the nonaqueous synthesis influenced subsequently dispersing [33], functionalization [34,35], or surface property tailoring [36,37].…”

Section: The Aggregation and Agglomeration Of Nanoparticles Dispersedmentioning

confidence: 99%

The Effect of Addition of Nanoparticles, Especially ZrO2-Based, on Tribological Behavior of Lubricants

Rylski

Siczek

2020

Lubricants

View full text Add to dashboard Cite

The aim of the paper was to discuss different effects, such as, among others, agglomeration of selected nanoparticles, particularly those from zirconia, on the tribological behavior of lubricants. The explanation of the difference between the concepts of ‘aggregation’ and ‘agglomeration’ for ZrO2 nanoparticles is included. The factors that influence such an agglomeration are considered. Classification and thickeners of grease, the role of additives therein, and characteristics of the lithium grease with and without ZrO2 additive are discussed in the paper. The role of nanoparticles, including those from ZrO2 utilized as additives to lubricants, particularly to the lithium grease, is also discussed. The methods of preparation of ZrO2 nanoparticles are described in the paper. The agglomeration of ZrO2 nanoparticles and methods to prevent it and the lubrication mechanism of the lithium nanogrease and its tribological evaluation are also discussed. Sample preparation and a ball-on disc tester for investigating of spinning friction are described. The effect of ZrO2 nanoparticles agglomeration on the frictional properties of the lithium grease is shown. The addition of 1 wt.% ZrO2 nanoparticles to pure lithium grease can decrease the friction coefficient to 50%. On the other hand, the agglomeration of ZrO2 nanoparticles in the lithium grease can increase twice the friction coefficient relative to that for the pure grease.

show abstract

Section: The Aggregation and Agglomeration Of Nanoparticles Dispersedmentioning

confidence: 99%

The Effect of Addition of Nanoparticles, Especially ZrO2-Based, on Tribological Behavior of Lubricants

Rylski

Siczek

2020

Lubricants

View full text Add to dashboard Cite

show abstract

“…The transient nature of intermediate species makes their characterization extremely challenging. For example, a recent study by Garnweitner and co‐workers showed the presence of defined oligomeric coordination complexes during the growth of anatase nanoparticles from titanium isopropoxide in benzyl alcohol . Using various NMR spectroscopy techniques and single crystal structure determination they were able to determine several intermediate species including a dimeric titanium benzyloxide [Ti(OBn) 4 (HOBn)] 2 with BnOH representing benzyl alcohol.…”

Section: Chemical Formation Mechanismsmentioning

confidence: 99%

“…Using various NMR spectroscopy techniques and single crystal structure determination they were able to determine several intermediate species including a dimeric titanium benzyloxide [Ti(OBn) 4 (HOBn)] 2 with BnOH representing benzyl alcohol. While this compound formed rather early in the synthesis, it was not recognized as the monomeric species for particle formation, but reacted to [Ti 16 O 16 ](OBn) 32 , which transformed into anatase …”

Section: Chemical Formation Mechanismsmentioning

confidence: 99%

“…For example, ar ecent study by Garnweitner and co-workers showedt he presence of defined oligomeric coordination complexes during the growth of anatase nanoparticles from titanium isopropoxidei nb enzyl alcohol. [122] Using various NMR spectroscopy techniques and single crystal structure determination they were able to determine severali ntermediates peciesi ncludingadimeric titaniumb enzyloxide [Ti(OBn) 4 (HOBn)] 2 with BnOH representing benzyl alcohol. While this compound formedr ather early in the synthesis, it wasn ot recognized as the monomeric species for particle formation,b ut reacted to [Ti 16 O 16 ](OBn) 32 ,w hich transformed into anatase.…”

Section: Chemical Formation Mechanismsmentioning

confidence: 99%

“…While this compound formedr ather early in the synthesis, it wasn ot recognized as the monomeric species for particle formation,b ut reacted to [Ti 16 O 16 ](OBn) 32 ,w hich transformed into anatase. [122] In spite of these findings about the complex nature of the intermediates, simplified schemes are still useful to explain many experimental observations and they provide valuablei nsight into the chemical pathways during the transformation of the precursors to the final nanoparticles.…”

Section: Chemical Formation Mechanismsmentioning

confidence: 99%

See 2 more Smart Citations

Mechanistic Aspects in the Formation, Growth and Surface Functionalization of Metal Oxide Nanoparticles in Organic Solvents

Deshmukh

Niederberger

2017

Chemistry A European J

106

112

View full text Add to dashboard Cite

The synthesis of metal oxide nanoparticles in organic solvents, so-called nonaqueous (or nonhydrolytic) processes represent powerful alternatives to aqueous approaches and have become an independent research field. 10 Years ago, when we published our first review on organic reaction pathways in nonaqueous sol-gel approaches, the number of examples was relatively limited. Nowadays, it is almost impossible to provide an exhaustive overview. Here we review the development of the last few years, without neglecting pioneering examples, which help to follow the historical development. The importance of a profound understanding of mechanistic aspects of nanoparticle crystallization and formation mechanisms can't be overestimated, when it comes to the design of rational synthesis concepts under minimization of trial-and-error experiments. The main reason for the progress in mechanistic understanding lies in the availability of characterization tools that make it possible to monitor chemical reactions from the dissolution of the precursor to the nucleation and growth of the nanoparticles, by ex situ methods involving sampling after different reaction times, but more and more also by in situ studies. After a short introduction to experimental aspects of nonaqueous sol-gel routes to metal oxide nanoparticles, we provide an overview of the main and basic organic reaction pathways in these approaches. Afterwards, we summarize the main characterization methods to study formation mechanisms, and then we discuss in great depth the chemical formation mechanisms of many different types of metal oxide nanoparticles. The review concludes with a paragraph on selected crystallization mechanisms reported for nonaqueous systems and a few illustrative examples of nonaqueous sol-gel concepts applied to surface chemistry.

show abstract

Particle-reinforced and functionalized hydrogels for SpineMan, a soft robotics application

et al. 2018

View full text Add to dashboard Cite

Formation of a Dimeric Precursor Intermediate during the Nonaqueous Synthesis of Titanium Dioxide Nanocrystals

Cited by 8 publications

References 64 publications

The Effect of Addition of Nanoparticles, Especially ZrO2-Based, on Tribological Behavior of Lubricants

The Effect of Addition of Nanoparticles, Especially ZrO2-Based, on Tribological Behavior of Lubricants

Mechanistic Aspects in the Formation, Growth and Surface Functionalization of Metal Oxide Nanoparticles in Organic Solvents

Particle-reinforced and functionalized hydrogels for SpineMan, a soft robotics application

Contact Info

Product

Resources

About