JP5005854B2 - Electrochemical devices - Google Patents

Description

・ガラス（１）は標準的な透明ケイ素−ナトリウム−カルシウム板ガラスである。
・フッ素ドープ酸化スズでつくられる層（２）はＣＶＤによる公知の方法で得られる第１の透明導電層である。
【００２９】
・ＮｉＯｘＨｙでつくられる層（３）は、対電極、系の陽極エレクトロクロミック物質であり、約９９．９５原子％のニッケルを含むニッケルターゲットからＡｒ／Ｏ₂／Ｈ₂反応性雰囲の存在下、陰極スパッタにより得られる；
・ＷＯ₃でつくられる層（４）およびＴａ₂Ｏ₅ でつくられる層（５）は、電解質を形成するが、Ｗの、およびＴａのターゲットから陰極スパッタにより公知の方法で堆積される（とくに特許ＥＰ８６７７５２の教示による）；
・ＨｘＷＯ₃ でつくられる層（６）は陰極エレクトロクロミック物質の層であり、タングステンターゲットから反応性スパッタにより公知の方法で堆積される；
・スズドープ酸化インジウムでつくられる層（７）は第２の透明導電層であり、インジウムおよびスズでつくられる合金ターゲットから陰極スパッタにより公知の方法で堆積される。
【００３０】
この窓ガラスは、適切な方法で窓ガラスにわたって発生される電位差を変えることによって、１つのエレクトロクロミック層から他の層へのプロトン移動により機能する。
ＮｉＯｘＨｙでつくられる層（３）は得るのが困難である。その堆積速度は４nm．ｍ／分にすぎない。ターゲットは均一には被覆されない（被覆度は５％未満である）。
本発明による実施例２
これは、ＮｉＯｘＨｙでつくられる層（３）を２５０ｎｍ厚さのＮｉＳｉｚＯｘＨｙでつくられる層３ａで置き換えることにあり、Ｎｉ＋Ｓｉに対するＳｉ約１０原子％の割合を有するＮｉ／Ｓｉ合金ターゲットからＡｒ／Ｏ₂／Ｈ₂反応性雰囲気中で陰極スパッタにより得られる。
本発明による実施例３
これはＮｉＯｘＨｙでつくられる層（３）を２５０nm厚さのＮｉＷｚＯｘＨｙでつくられる層３ｂで置き換えることにあり、Ｎｉ＋Ｗに対するＷ約７原子％の割合を有するＮｉ＋Ｗ合金ターゲットから上述のように得られる。下の表１は上の３つの実施例により得られる、酸化ニッケルにもとづく層の堆積速度を示し、これらの速度はnm．ｍ／分（３．５ｗ／cm² での堆積）で表される：
【００３１】
【表１】

上述の層で被覆されたガラスは、電圧発生器に公知の方法で連結される電力供給を備える。ついで、それらは１．２５mm厚さのポリウレタンシートにより第１と同一の第２ガラスで積層される。
【００３２】
３つの積層窓ガラス試料は、ついで、発色／消色サイクル（約−１．２Ｖの電圧を印加することにより発色、そして約０．８Ｖの電圧を印加することにより消色）に供された。窓ガラス試料が発色され（「発色」）、ついで消色される（「消色」）されるときに、光透過における測色系（Ｌ，ａ^*，ｂ^*）のａ^*およびｂ^*の光透過率Ｔ_L （％）、ならびにエネルギー伝達率Ｔ_E （％）（Ｔ_L 測定に対する対照：発光体Ｄ₆₅）が、ついで測定され、下の表２は３つの窓ガラス試料に関するすべてのこれらのデータを一緒にする：
【００３３】
【表２】

これらのデータから、酸化ニッケルにもとづくエレクトロクロミック物質になされた変化はその性能に影響しないことを確かめることができる：
本発明による実施例２および３で達成される光透過率の範囲およびエネルギー伝達の範囲は比較例１のとほとんど同一であり、透過の測色状況は有意には変わっていない。一方、本発明による酸化ニッケルにもとづく層の堆積速度は、酸化ニッケルにもとづく標準的な層の堆積速度より少くとも５倍は高い。[0001]
The present invention relates to electrochemical devices, and in particular to electrochromic glazing or mirror-type electrically controllable systems with variable optical and / or energetic properties.
[0002]
In a known manner, an electrochromic system consists of a layer from an electrochromic material that can reversibly and simultaneously insert ions and electrons, whose oxidation state corresponding to the insertion and de-insertion states is clearly colored. One of the states exhibits greater light transmission than the other, and the insertion and de-insertion reactions are controlled by a suitable electrical supply. Electrochromic materials, usually based on tungsten oxide, must be placed in contact with an electron source such as a transparent electrically conductive layer and an ion (cation or anion) source such as an ion conducting electrolyte.
[0003]
Furthermore, in order to ensure at least hundreds of switching operations, the electrochromic material layer must be combined with a counter electrode that can reversibly insert ions, and is symmetrical with the electrochromic material, Macroscopically, the electrolyte looks like a single medium of ions.
The counter electrode consists of an intermediate color layer, or a layer that is at least slightly colored when the transparent or electrochromic layer is in the colored state. Tungsten oxide is a cathode coloring material, that is, its coloring state corresponds to the most reduced state, so an anodic electrochromic material based on nickel oxide or iridium oxide is generally used as a counter electrode. . It has also been proposed to use substances that are optically neutral in the oxidized state, for example cerium oxide, or organic substances such as electron conducting polymers (polyaniline, etc.), or Prussian blue.
[0004]
A description of such a system can be found, for example, in European patents EP338876, EP408427, EP575207 and EP628849.
These systems can now be classified into two categories depending on the type of electrolyte used.
The electrolyte is in the form of a polymer or gel, for example a proton conducting polymer as disclosed in European patents EP253713 and EP670346, or a lithium ion transport polymer as disclosed in patents EP382623, EP518754 or EP532408.
[0005]
The electrolyte is an inorganic layer that conducts ions but is electronically insulative, and such a system is referred to as an “all-solid” electrochromic system. Reference can be made to European patent applications EP8677752 and EP831360 for a description of “all-solid” electrochromic systems.
The present invention is particularly directed to obtaining an anode electrochromic material layer based on nickel oxide that can form part of such an electrochromic system.
[0006]
As mentioned above, nickel oxide is known to have such properties and is described in particular in patent EP373020.
However, this material has weaknesses: a problem arises in obtaining it in the form of a thin layer by standard vacuum deposition methods, magnetic field assisted reactive cathodic sputtering: since nickel is ferromagnetic, a standard nickel target And with standard magnets, the magnetic field that appears on the surface of the target is weak, resulting in low deposition rates and mediocre target utilization.
[0007]
This type of material was also discussed in patent application WO 98/14824: For use in electrochromic mirrors, considerations have been made for nickel oxides alloyed with another metal such as vanadium, chromium, manganese, iron or cobalt. Implemented, this compositional change is stated to improve the function of the mirror and give a particularly uniform coloration.
[0008]
However, this introduction of other metals into nickel oxide seems dangerous with respect to the optical and electrochromic properties of nickel oxide. Thus, for example, the introduction of vanadium and chromium means that the oxide absorbs in the visible region, and nickel oxide is more likely to be an absorbent, and thus tends to reduce the light transmission value of the active system as a whole in the decolored state. There may be a fear. Similarly, the introduction of manganese, iron and cobalt can tend to reduce the durability of the layer, and overall the active system.
[0009]
The object of the present invention is thus to ameliorate these weaknesses, in particular by proposing a new method for producing nickel oxides having anodic electrochromic properties, which production method is implemented in particular. It is faster, more economically feasible, simpler, and does not otherwise detract from the desirable functionality of nickel oxide. “Functionality” means stability, durability of electrochromic systems, especially H ⁺ conductivity, or Li ⁺ conductivity and “all solid” types, and in the decolored state when in thin layers Specially directed to transparency.
[0010]
The subject of the present invention is an essentially metal target of a cathode sputtering device, preferably a magnetic field assist device in a reactive atmosphere in the presence of oxygen, in particular to obtain the corresponding metal oxide as a thin layer The target is primarily nickel and is mixed with at least one other sub- element to reduce or even eliminate its ferromagnetism, but at the same time the mixed obtained from this target Maintain the optical and / or electrochemical properties of the nickel oxide as much as possible.
[0011]
In particular, the present invention is thus based on nickel oxide, which is much faster and more economically feasible as a target without degrading functionality by carefully adding selected elements to the target. This provides an advantageous harmony that allows the layers to be obtained by reactive sputtering. The greatest effect of increasing production efficiency is achieved by sufficiently eliminating the ferromagnetism of nickel, but by appropriately changing the chemical nature of the added element and the amount of this element incorporated into the target. It can be chosen simply to reduce ferromagnetism.
[0012]
In general, the proportion of this or a mixture of these subelements is not more than 20 atomic%, preferably not more than 18%, and for example 3% to 15%, relative to the combined nickel and subelements .
For purposes of the present invention, “nickel oxide” can be hydrated and / or hydroxylated and / or protonated (and optionally nitrided to varying degrees. Similarly, the stoichiometry of nickel and oxygen is In general, the Ni / O ratio can vary from 1 to 1/2, but nickel can generally be considered primarily in the +2 oxidation state.
[0013]
Different variations are possible with respect to the target chemistry and these are alternative or progressive variations.
The first variation is in a subelement (hereinafter referred to as “additive” for simplicity) whose metal is an electrochromic material having an anodic color. It may in particular be at least one of the following metals: Ir, Ru, Rh. Ideally, in addition, iridium is most preferred, and the corresponding oxide has an operating voltage range that is the same as or close to that of nickel oxide: rather than interfering with the functionality of nickel oxide, the additive is nickel oxide. It can be kept intact and can even increase the reversible ion insertion capacity. In this case, it can even be expected to reduce the layer thickness while still retaining the same level of optical / energy change as the relatively thick layer of nickel oxide.
[0014]
The second variant resides in an additive whose oxide is a metal that is an electrochromic material having a cathodic color. It may in particular be at least one of the following metals: Mo, W, Re, Sn, In, Bi. Introducing such materials into nickel oxide in this way may seem contradictory and result in interference. Indeed, the metal oxides described above have been found to have anion insertion capability in the operating voltage range far exceeding the potential achieved by nickel oxide used as the anodic electrochromic material. Thus, these additives found effectively in the oxidized form in nickel oxide remain inert and colorless when the nickel oxide undergoes color variations due to being placed on voltage: these additives Is neutralized when the active system functions and does not reduce its light transmission level in the decolored state. On the other hand, their presence tends to reduce the ion insertion capacity of the layer as a whole, and therefore, if necessary, it is possible to slightly increase the thickness to be compensated for this phenomenon, and this magnitude is It can also be considered for deformation.
[0015]
The third variant is in an additive obtained from a metal, alkaline earth metal or semiconductor whose hydration and / or hydroxide oxide is the proton conductor. It may in particular be at least one of the following elements: Ta, Zn, Zr, Al, Si, Sb, U, Be, Mg, Ca, Y. These materials in oxidized form do not have significant electrochromic properties. On the other hand, they are known for their ability to serve as substances that can serve as proton conducting electrolytes in electrochromic systems: they do not inherently promote the electrochromic properties of nickel oxide, but they are negative for their functionality anyway. It has no effect and tends to promote the hydroxylation / hydration stability that can be desired for nickel oxide. Of course, it should be noted that this variation is essentially directed to an electrochromic system that functions by reversible insertion of proton H ⁺ .
[0016]
The fourth variant is in an additive whose oxide is an element that is hygroscopic, this feature being one function by the insertion / deinsertion of an electrochromic system, most preferably a cation such as a proton. Is advantageous. These additives are usually alkali metals, in particular Li, Na, K, Rb, Cs. When in the oxidized form in nickel oxide, these materials act as anodic electrochromic materials in the electrochromic system, most particularly when the nickel oxide is hydrated / hydroxylated, the water contained in the layer. It can be seen that the stability of nickel oxide is improved by probably promoting retention.
[0017]
Preferred embodiments of the target of the present invention are the alloys Ni / Si, Ni / Al, Ni / Sn, Ni / W, Ni / Zn, Ni / Ta and Ni / Y, the first three alloys being manufactured. It is relatively inexpensive. The alloy target is produced by methods known in the field of vacuum deposition, for example by high temperature sintering of metal powders to be alloyed. Noted for atomic ratios of additives with respect to the entire conceivable alloy is made below, the ratio is adjusted so that the ferromagnetic targets are sufficiently erased:
• For Ni / W alloys, it is necessary to supply about 7 atomic percent tungsten W.
[0018]
• For Ni / Zn alloys, it is necessary to supply about 18 atomic percent zinc Zn.
• For Ni / Ta alloys, it is necessary to supply about 9 atomic% tantalum Ta.
• For Ni / Sn alloys, it is necessary to supply about 8 atomic percent tin Sn.
[0019]
• For Ni / Si alloys, it is necessary to supply about 10 atomic percent silicon Si.
It is necessary to supply about 3 atomic% yttrium Y for the Ni / Y alloy.
However, as described above, it is necessary to sufficiently erase its ferromagnetism, for example, to limit the manufacturing cost of the target and / or to limit the decrease in functionality of the resulting nickel alloy oxide. It may also be chosen to add lesser amounts of additive to the nickel.
[0020]
The subject of the invention is furthermore a method for the production of a thin layer based on nickel alloy oxide, which is optionally hydrated and / or hydroxylated and / or protonated and / or nitrided and A magnetic field assisted cathode sputtering method is used in an oxidizing reactive atmosphere from a target.
Furthermore, the subject of the present invention is the use of this method of manufacturing anodic electrochromic materials such as thin layers based on the oxide.
[0021]
Furthermore, the subject of the present invention is a stack of functional layers including at least one electrochemically active layer capable of reversibly and simultaneously inserting ions and electrons such as H +, Li + and OH− . An electrochemical device consisting of at least one carrier substrate comprising a layer based on the oxide.
This oxide is obtained from a target whose composition has been revealed in the four variants outlined above. In addition, the atomic ratio of the additive to nickel in the target alloy is generally within the range of the atomic ratio of the additive to nickel in the oxide layer obtained from the target under consideration. It can be noted.
[0022]
It has been found that the addition of the additive according to the present invention to the nickel target affects the structure of the oxide layer obtained from the target. The presence of the additive seems to dislike the crystallization of nickel oxide: a layer that is primarily amorphous can be obtained in this way, but it is most particularly W, Si and Li type to have small crystal “grains”. Was confirmed for the additives. Approximating these shapes to spheres, these grains usually have a diameter of less than 50 nm, in particular at least 2-3 nm. It is advantageous to have a larger amorphous phase and / or smaller grains than in standard nickel oxide. This is because the electrochromic device that utilizes the electrochromic properties of nickel oxide is particularly active in the amorphous part of the layer rather than the crystalline part. The layer according to the invention therefore does not have a sheet structure with Li-type intercalation compounds between the sheets, but rather an overall amorphous structure that is distributed uniformly as grains.
[0023]
The layer is based on nickel oxide optionally treated with hydration / hydration and / or nitride, the nickel oxide being at least 1 in which the oxide is an anodic electrochromic material, such as Ir, Ru or Rh. Alloyed with one additive or alloyed with at least one metal whose oxide is a cathodic electrochromic material, such as Mo, W, Re, Sn, In or Bi Or at least one alkaline earth whose hydrated and / or hydroxide oxides such as Ta, Zn, Zr, Al, Si, Sb, U, Mg, La or Y are proton conductors Alloyed with metal or semiconductor. Finally, nickel oxide can be alloyed with an additive whose oxide is hygroscopic, for example an alkali metal such as Li, Na, K, Rb or Cs.
[0024]
It should be noted here that the term “alloyed” has the following meaning: the additive is combined with nickel oxide in oxide form. The oxide may be in the form of a matrix formed from nickel oxide microdomains, the interior of which is a microdomain based on the oxide of the additive. The system may further be a pure mixed oxide, whose nickel atoms are replaced by atoms of the additive.
[0025]
Preferred embodiments are NiSixOy, NiAlxOy, NiSnxOy, NiWxOy, NiZnxOy, NaTaxOy and NiYxOy.
Furthermore, the resulting layer may be hydrated and / or hydroxylated and / or protonated and / or nitrided, to the extent of hydration, protonated and / or hydroxylated and / or nitrided of the layer. Control is achieved in particular by appropriately adjusting the cathode sputter deposition parameters, for example by adapting the composition of the reactive atmosphere during deposition (as specifically expected for the electrolyte layer in patent EP831360). The reactive atmosphere may specifically contain a certain amount of molecules, at least one atom of which is nitrogen.
[0026]
Finally, a further subject of the present invention is the use of these electrochemical devices to form part of an electrochromic glazing. This window glass can be provided in a building as an external window glass or an internal partition or a door fitted with a window glass. Furthermore, it can be provided as a side window, sunroof etc. in transportation means such as trains, ships, airplanes, passenger cars or trucks. In addition, it can be used for display screen panes, such as computer or television screens or touch screens, glasses, objectives for photographic articles and solar panel protection. It can also be used to make mirrors, such as vehicle anti-glare rearview mirrors (by making one of the conductive layers sufficiently thick and / or by applying an opacifying coating). It can also be used to manufacture batteries and energy storage devices such as batteries.
[0027]
Other advantageous details and features of the invention will now become apparent from various non-limiting embodiments.
The next example is a so-called “all-solid” electrochromic glazing.
Comparative Example 1
The window glass has the following arrangement:
[0028]
[Chemical 1]

Glass (1) is a standard transparent silicon-sodium-calcium plate glass.
The layer (2) made of fluorine-doped tin oxide is a first transparent conductive layer obtained by a known method by CVD.
[0029]
Layer (3) made of NiOxHy is a counter electrode, system anodic electrochromic material, from a nickel target containing about 99.95 atomic% nickel in the presence of an Ar / O ₂ / H ₂ reactive atmosphere Obtained by cathodic sputtering;
The layer (4) made of WO ₃ and the layer (5) made of Ta ₂ O ₅ form an electrolyte but are deposited in a known manner by cathode sputtering from W and Ta targets (especially According to the teaching of patent EP8677752);
The layer (6) made of HxWO ₃ is a layer of cathodic electrochromic material, deposited in a known manner by reactive sputtering from a tungsten target;
The layer (7) made of tin-doped indium oxide is the second transparent conductive layer and is deposited in a known manner by cathode sputtering from an alloy target made of indium and tin.
[0030]
This glazing functions by proton transfer from one electrochromic layer to another by changing the potential difference generated across the glazing in an appropriate manner.
The layer (3) made of NiOxHy is difficult to obtain. The deposition rate is 4 nm. Only m / min. The target is not uniformly coated (coverage is less than 5%).
Example 2 according to the invention
This is to replace the layer (3) made of NiOxHy with a layer 3a made of NiSizOxHy with a thickness of 250 nm, from an Ni / Si alloy target having a ratio of about 10 atomic% of Si to Ni + Si from Ar / O ₂ / Obtained by cathode sputtering in an H ₂ reactive atmosphere.
Example 3 according to the invention
This consists in replacing the layer (3) made of NiOxHy with a layer 3b made of NiWzOxHy with a thickness of 250 nm, obtained as described above from a Ni + W alloy target having a ratio of about 7 atomic% W to Ni + W. Table 1 below shows the deposition rates of the layers based on nickel oxide obtained by the above three examples, these rates being in nm. Expressed in m / min (deposition at 3.5 w / cm ² ):
[0031]
[Table 1]

The glass coated with the above-mentioned layer comprises a power supply which is connected to the voltage generator in a known manner. They are then laminated with the same second glass as the first with a 1.25 mm thick polyurethane sheet.
[0032]
The three laminated glazing samples were then subjected to a color development / decoloring cycle (color development by applying a voltage of about -1.2V and color erasure by applying a voltage of about 0.8V). When a window glass sample is colored (“colored”) and then decolored (“decolored”), the colorimetric system (L, a ^* , b ^* ) of a ^* and b ^* in light transmission The light transmission T _L (%), as well as the energy transfer rate T _E (%) (control for T _L measurement: illuminant D ₆₅ ) was then measured, and Table 2 below shows all these for three pane samples. Put the data together:
[0033]
[Table 2]

From these data, it can be confirmed that changes made to the electrochromic material based on nickel oxide do not affect its performance:
The range of light transmittance and the range of energy transmission achieved in Examples 2 and 3 according to the present invention are almost the same as those of Comparative Example 1, and the colorimetric state of transmission is not significantly changed. On the other hand, the deposition rate of the layer based on nickel oxide according to the invention is at least five times higher than the deposition rate of a standard layer based on nickel oxide.

Claims (1)

A method for producing an electrochemical device comprising at least one carrier substrate comprising a stack of functional layers comprising at least one electrochemically active layer capable of reversibly and simultaneously inserting ions and electrons. The method includes magnetic field assisted cathode sputtering using a nickel-based target in an oxidation reactive atmosphere, and materials to be alloyed with nickel oxide include Ir, Ru, Rh, Mo, W, Re, Sn, In, and Bi. , Ta, Zn, Zr, Al, Si, Sb, U, Be, Mg, Ca and Y , where the layer based on the nickel-based target and nickel oxide is
(1) The nickel-based target is a Ni / Si alloy target and the layer based on nickel oxide is in the form of NiSi _x O _y ;
(2) The nickel-based target is a Ni / Al alloy target, and the layer based on nickel oxide is in the form of NiAl _x O _y ;
(3) The nickel-based target is a Ni / Zn alloy target and the layer based on nickel oxide is in the form of NiZn _x O _y ;
(4) Nickel-based target is a Ni / Ta alloy target, a layer based on nickel oxide is in the form of a NiTa _x O _y; or
(5) a nickel-based target is Ni / Y alloy target, a layer based on nickel oxide Ru form der of _NiY x _{O y,} a method for manufacturing an electrochemical device.