Titanium Dioxide Nanomaterials: Synthesis, Properties, Modifications, and Applications

In the present review we try to give a comprehensive and most up to date view to the field, with an emphasis on the currently most investigated anodic TiO2 nanotube arrays. We will first give an overview of different synthesis approaches to produce TiO2 nanotubes and TiO2 nanotube arrays, and then deal with physical and chemical properties of TiO2 nanotubes and techniques to modify them. Finally, we will provide an overview of the most explored and prospective applications of nanotubular TiO2.

One-dimensional titanium dioxide nanomaterials: nanotubes.

https://hal.archives-ouvertes.fr/hal-00120432/document

Raman Spectroscopy of Nanomaterials: How Spectra Relate to Disorder, Particle Size and Mechanical Properties

Nanostructured oxides in chemistry: characterization and properties.

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...

Hydrothermal synthesis of graphene-TiO 2 nanotube composites with enhanced photocatalytic activity

Titanium dioxide (TiO2 ) nanocrystals are prepared by a hydrolysis process of tetrabutyl titanate. Nanocrystal samples with various sizes of 6.8-27.9 nm are obtained after annealing from 100 to 650 °C. The crystal structures and the average particle sizes are examined using x-ray diffraction. Raman scattering was employed to investigate the evolution of the anatase phase in the nanocrystals during annealing. Phonon confinement and non-stoichiometry effects are responsible for the blueshift and broadening of the lowest-frequency Eg Raman mode. The influence of interfacial vibrations on the Raman linewidth is also discussed.

https://iopscience.iop.org/article/10.1088/0022-3727/33/8/305/pdf

Raman scattering study on anatase TiO2 nanocrystals

An energy-efficient tactile-sensing element composed of a triboelectric nanogenerator (TENG) and an electrolyte-gated synaptic transistor (EGT) is presented for biological tactile sensory neuron emulation. As the mechanoreceptor, TENG converts pressure signals into voltage pulses directly. The EGT is used as a neuromorphic device to emulate the behaviors of biological synapse. Typical functions of tactile sensory neuron to perceive dynamic pressures with different intensities, amounts and frequencies are studied. Besides, spiders’ ability of identifying prey by sensing the vibrations of cobweb is also emulated.

Oxide Synaptic Transistors Coupled With Triboelectric Nanogenerators for Bio-Inspired Tactile Sensing Application

The biological visual system encodes optical information into spikes and processes them by the neural network, which enables the perception with high throughput of visual processing with ultralow energy budget. This has inspired a wide spectrum of devices to imitate such neural process, while precise mimicking such procedure is still highly required. Here, a highly bio‐realistic photoelectric spiking neuron for visual depth perception is presented. The firing spikes generated by the TaOX memristive spiking encoders have a biologically similar frequency range of 1–200 Hz and sub‐micro watts power. Such spiking encoder is integrated with a photodetector and a network of neuromorphic transistors, for information collection and recognition tasks, respectively. The distance‐dependent response and eye fatigue of biological visual systems have been mimicked based on such photoelectric spiking neuron. The simulated depth perception shows a recognition improvement by adapting to sights at different distances. The results can advance the technologies in bioinspired or robotic systems that may be endowed with depth perception and power efficiency at the same time.

A Photoelectric Spiking Neuron for Visual Depth Perception

In recent years, the rapid increase in the data volume to be processed has led to urgent requirements for highly efficient computing paradigms. Brain-like computing that mimics the way the biological brain processes information has attracted growing interest due to extremely high energy efficiency. Particularly, dynamics play an essential role in neural spike information processing. Here, we offer a brief review and perspective in the field of electrolyte-gated neuromorphic transistors for brain-like dynamic computing. We first introduce the biological foundation of dynamic neural functions. Then dynamic synaptic plasticity, dynamic dendritic integration, dynamic neural functions, and bio-inspired somatosensory systems realized based on the electrolyte-gated neuromorphic transistors are presented. At last, conclusions and perspectives are given.

Yongli He

Papers

Raman scattering study on anatase TiO2 nanocrystals

Oxide Synaptic Transistors Coupled With Triboelectric Nanogenerators for Bio-Inspired Tactile Sensing Application

A Photoelectric Spiking Neuron for Visual Depth Perception

Electrolyte-gated neuromorphic transistors for brain-like dynamic computing

Indium-Gallium-Zinc-Oxide Based Photoelectric Neuromorphic Transistors for Modulable Photoexcited Corneal Nociceptor Emulation