Electrical transparent conductor

The combination of low optical absorbance and high electrical conductivity has attracted a lot of interest for transparent conductor applications. When coupled with its flexibility, it is widely seen as a possible replacement for indium-doped tin oxide (ITO), which has a sheet resistance of 100 Q/cm at 90 % transparency. By growing graphene on copper foils, sheet resistances of 125 Q/cm at 97.4% transparency have been achieved [19]. This has been improved by combining four layers with doping of the graphene, giving resistance of 30 Q/cm at 90% transparency, all done on 30-inch roll-to-roll production scale. 

In addition to their potential use as structural composites, these macroscopic assemblies of nanocarbons have shown promise as mechanical sensors [83], artificial muscles [84], capacitors [85], electrical wires [59], battery elements [85], dye-sensitized solar cells [86], transparent conductors [87], etc. What stands out is not only the wide range of properties of these type of materials but also the possibility of engineering them to produce such diverse structures, ranging from transparent films to woven fibers. This versatility derives from their hierarchical structure consisting of multiple nano building blocks that are assembled from bottom to top. 

CD Cu-S(e) films have been proposed for a number of different potential applications. Solar control coatings, where the visible and IR transmission and reflectivity can be varied, is probably the most studied, e.g.. Refs. 44 and 45. The relatively high conductivity and the partial transmittance in the visible spectrum are useful for transparent conductors [46]. Other possible applications are for Cu sensor electrodes and electrical contacts for ceramic devices [46]. 

Electrical conductivity measurements of the as-deposited ln(OH)s showed an expectedly high resistivity of ca. 10 ff-cm. That of the annealed oxide film decreased to 33 O-cm (carrier concentration = 1.85 X 10 cm mobility = 10 cm V sec ). The resistivity is high compared to many other ln20s films (which are often used as transparent conductors), mainly due to the low carrier concentration, implying a high degree of stoichiometry. 

In conclusion, for both AP-CVD and LP-CVD processes, only a narrow range of temperatures can be identified for optimum performance (a range that is typically 40°C-wide). Within this narrow temperature range highly oriented films are obtained that have electrical and optical properties suitable to act as transparent conductors in solar cells. The typical substrate temperature is around 400°C for the AP-CVD process, whereas it is around 160°C for the LP-CVD process. The two processes yield film orientations that are perpendicular to each other. 

The standard EL device (Fig. 1 b) employs a transparent substrate, typically glass, coated with a transparent conducting layer, which serves as the bottom electrode. The bottom insulator, phosphor, and top insulator layers reside between the bottom transparent conductor and a top opaque conducting layer. This layer serves both as an electrical contact and as a reflector to direct light generated in the phosphor layer... 

Electrically Conducting Coatings PEDTiPSS as a Transparent Conductor in Electroluminescent Devices ... 

Advances in nano-material research have opened the door for transparent conductive materials, each with unique properties. These include CNTs, graphene, metal nanowires, and printable metal grids. Transparent electrodes are necessary components in many modem devices such as touch screens, LCDs, OLEDs, and solar cells, all of which are growing in demand. Traditionally, this role has been well served by doped metal oxides, such as indium tin oxide. A review exploring these innovations in transparent conductors and the emerging trends is presented recently (Hecht et al. 2011). Electrical conductivity in PS nanocomposites with ultralow graphene level was found to enhance significantly (Qi et al. 2011). 

Electrochromism is defined as a persistent but reversible optical change in absorption or reflection produced electrochemically in a medium by an applied electric field or current. An electrochromic device in which this process can be realized is schematically shown in Figure 1. Generally such a device contains transparent conductors, an ion storage layer, an ionic conductor and an optically active electrochromic layer. We will focus on properties of the ionic conductor. 

Engineering plastics can be flexible and offer advantages such as transparency, self-lubrication, economy in fabricating, and decorating. Plastics are electrical non-conductors and thermo insulators. Plastics are considered to be competitive primarily with metals. Compared to metals, plastics are easier to fabricate and low cost. Plastics can be pigmented in a wide variety of colors. 

This section aims at providing a clear illustration as to what extent CNT length and quality can impact the electrical conductivity of polymer nanocomposites. The latter strongly determines for which applications, for example, electromagnetic interference (EMI) shields and electrostatic discharge (ESD) coatings, or thin-film field-emitters and (at low CNT concentrations) transparent conductors, the final materials are suitable (see Figure 7.1). 

Solar cells that convert sunlight directly into electricity work on the same principle as shown in Figure 21.19. The top electrode can be a web of thin wires to collect the charge or a transparent conductor such as ITO. 

Referring to Tables 5-1 and 5-II, we find that both sodium chloride and copper have extremely high melting and boiling points. These two solids have little else in common. Sodium chloride has none of the other properties that identify a metal. It has no luster, rather, it forms a transparent crystal. It does not conduct electricity nor is it a good heat conductor. The kind of forces holding this crystal together must be quite different from those in metals. 

In diamond, each carbon atom is sp3 hybridized and linked tetrahedrally to its four neighbors, with all electrons in C C cr-bonds (Fig. 14.30). Diamond is a rigid, transparent, electrically insulating solid. It is the hardest substance known and the best conductor ol heat, being about five times better than copper. These last two properties make it an ideal abrasive, because it can scratch all other substances, yet the heat generated by friction is quickly conducted away. 

This chapter is a review of the two major allotropes graphite and diamond, which are both produced extensively by CVD. The properties of these two materials can vary widely. For instance, diamond is by far the hardest-known material, while graphite can be one of the softest. Diamond is transparent to the visible spectrum, while graphite is opaque diamond is an electrical insulator, while graphite is a conductor. 

Tin oxide, Sn02, has unusual physical properties. It is a good electrical conductor. It is highly transparent to the visible and highly reflective to the infrared spectrum. It is deposited extensively by CVD mostly for optical applications. Its characteristics and properties are summarized in Table 11.6. 

Metallic lead is dark in color and is an electrical conductor. Diamond, the most valuable form of carbon, is transparent and is an electrical insulator. These properties are very different yet both lead and carbon are in Group 14 of the periodic table and have the same valence configuration, s p Why, then, are diamonds transparent insulators, whereas lead is a dark-colored conductor ... 

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