Metal doped/functionalized

The TID design proposed Patterson consists of an alkali metal doped cerwlc cylinder, containing an embedded heater surrounded by a cylindrical collector electrode [100]. The ceramic thermionic emitter is biased at a negative potential with respect to the collector electrode, and it is heated to a surface temperature of 400-800 C, depending on the mode of detection. The response of the detector to different elements depends on the electronic work function of the thermionic surface (i.e., the... 

EPR studies of metal-doped Ti02 and other oxide colloids were used for structural and functional characterization of such materials. This information is spread in many original articles, and was partially collected in [21, 220-222]. Various paramagnetic ions such as Mo5+, W5+, Cr5+, Nb4+, Ta4+, Mn4+, Mn3+, Cr3+, Fe3+, Ce3+, Al3+, Pt3+, Ni3+, Ni2+, Ni+, Co2+, Cu2+, etc., were used as spin dopants. As in the previous paragraph, Table 8.9 contents the spin-Hamittonian parameters of metal centers in Ti02 (rutile - R, anatase - A, brookite - B), and the same data concerning other wide bandgap semiconductor oxides are collected in Table 8.10. 

Schottky contact — Alternative denomination of metal-semiconductor contact presenting a Schottky barrier. Depending on metal - work function, semiconductor electron affinity, doping of the semiconductor, conditions of the surface of the semiconductor before contact preparation, and preparation process, Schottky contacts with high rectification can be prepared. Devices encor-porating such contacts behave like a diode and for this reason, are also denominated Schottky diodes, whose main features are the capability of high frequency operations and low forward-voltage drop. 

Metal-doped silica gels exhibit a wide range of optical properties which allow them to be used for optical and optoelectronic triplications. The preparation is done via the sol-gel process. Emission and absorption maxima as well as quantum yield can be adjusted by built-in functionalized silanes [2] or adsorbed semiconductor or metal colloids, respectively [3,4]. 

It is our aim to combine the outstanding properties of nano- microtubes and metal-doped silica gel. There are many kinds of dopands, e.g., transition metal and rare-earth ions. A further advantage is the high heat resistance of these tubular structures up to 250 °C with organically functionalization, and up to 800 °C with only metal functionalization. Metal ions can be built directly in the silica backbone or adsorbed on the surface. Functionalized silanes can also be used to coordinate metal ions and build them into the tubes. 

RATIONALLY DESIGNED OXIDATION CATALYSTS FUNCTIONALIZED METALLOPORPHYRINS ENCAPSULATED IN TRANSITION METAL-DOPED MESOPOROUS SILICA (abstract)... 

Fig. 21. The plot of b for Schottky barriers on a-Si H (O) and n-doped crystalline Si ( ) versus metal work function. The dashed line is the expected behavior for the metal work-fimc-tion model (Og =1-00, m 4.05) and the solid lines are fits to the data for models that include interface states. The fits give 4>b = 0.44 for a-Si H and b 4>m 0.55 for n-doped c-Si.

In conducting polymers, the extra carriers added upon doping are able to drift under an applied electrical field. In semiconducting polymers, no carriers are available except those thermally excited across the gap. However, negative (positive) carriers can be injected into the material by metallic contacts when the barrier between the metal work function and the LUMO (HOMO) molecular levels is overcome. Then, the injected carriers can move inside the semiconductor if a bias field is applied. Injection of carriers and their transport is a fundamental issue for all electronic devices and transistors in particular. In the following, main transport properties of organic semiconductors (both small molecules and polymers-based) used as active materials in transistors will be reviewed. 

In this chapter, first the ionic reaction equilibrium, phase behavior, and solubility of metal oxides in supercritical water are discussed. Next, the specific features of hydrothermal synthesis under supercritical conditions are discussed based on the experimental results. The supercritical hydrothermal crystallization method was applied to the production of functional materials, barium hexaferrite (BaFei20i9), metal-doped oxide [Al5(Y- -Tb)30i2, YAG Tb], and Li ion battery cathode material (LiC02O4). The importance of understanding the chemical reaction equilibrium and phase behavior is discussed. 

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