Quick Search




CAS NO: 12021-95-3

EC NO: 234-666-0


Hexafluorozirconic acid is an inorganic acid composed of H2 [ZrF6], transition metal zirconium and halogen fluorine. Its salts are hexafluorozirconates.

This substance is used in articles, by professional workers (widespread uses), in formulation or re-packing, at industrial sites and in manufacturing.

Hexafluorozirconic acid , H 2 [ZrF 6 ], is an inorganic acid consisting of the transition metal zirconium and the halogen fluorine . Their salts are the hexafluorozirconates.

The acid and its salts are used in metal surface technology.

A 45% aqueous solution of hexafluorozirconic acid is an odorless, colorless liquid. It has a density of 1.51 g · cm −3 .The pH value is <1 at 20 ° C. 

An inorganic compound aqueous solution used mainly used in manufacturing of optical glass and fluozirconate,in the metal industry as corrosion inhibitor for surface pre-treatment. It is most effective on aluminum, but can also used on other metals.


Hexafluorozirconic Acid Synonyms:

Hexafluorozirconic acid; Hexafluorozirconic acid solution; Hexafluorzirkonsaurelosung; Tetrafluorozirconium; dihydrofluoride; AKOS015903617; zirconium (IV) fluoride dihydrofluoride; FT-0627006; Hexafluorozirconic acid solution, 50 wt. % in H2O; J-521444; Q62018152; Dihydrogen hexafluorozirconate solution; Hexafluorozirconic acid; Hexafluorozirconic acid solution; Hydrogen zirconium fluoride; MFCD00082965; Tetrafluorozirconium dihydrofluoride; Tétrafluorozirconium, difluorhydrate; Tetrafluorzirconiumdihydrofluorid; Dihydrogen hexafluorozirconate; ZIRCONIUM TETRAFLUORIDE DIHYDROFLUORIDE

What is Hexafluorozirconic Acid?

Hexafluorozirconic acid (HFZA) is mainly used as a corrosion inhibitor by customers operating in the metal and plating industry. Although it can be used on other metals, it shows the highest efficiency on aluminum.

Customers are using Hexafluorozirconic acid as an alternative to nickel-based products with less hazardous properties when it comes to environmental and health and safety regulations. Hexafluorozirconic acid applications include electroplating, aluminum varnishing in chromium-free processes, synthesis of fluoride-releasing dental monomers as the precursor to ZrO2 ceramic films, and metal.

Hexafluorozirconic acid reduces sludge formation as a by-product - eg. In zinc phosphate based systems. A new phosphate-free pretreatment from Henkel Corp. named TecTalisâ, was
investigated. The treatment bath is composed of dilute hexafluorozirconic acid with small
quantities of non-hazardous components containing Si and Cu. The performance of
treated steel was compared to samples treated in a phosphate conversion coating bath, in
simple hexafluorozirconic acid and in TecTalis without the addition of the Cu containing
component. Atomic Force Microscopy (AFM) and Transmission Electron Microscopy
(TEM) were used to characterize the coating surface morphology, structure and
composition. A Quartz Crystal Microbalance (QCM) was used for studying film growth
kinetics on thin films of pure Fe, Al and Zn. Electrochemical Impedance Spectroscopy
(EIS) was performed on treated and painted steel for studying long-term corrosion
performance of the coatings. The phosphate-free coating provided long-term corrosion
performance comparable to that of phosphate conversion coatings. The coatings
uniformly cover the surface in the form of 10-20 nm sized nodules and clusters of these
features up to 500 nm in size. The coatings are usually about 20-30 nm thick and are
mostly composed of Zr and O with enrichment of copper at randomly distributed
locations and clusters.

7XXX aluminum alloys show high mechanical resistance and low weight, both required properties for aircraft industry. Anodizing is an electrolytical process typically used to improve the corrosion resistance of aluminum alloys, through which a thicker and porous oxide is formed. Boiling water is used as a common sealing method to the anodic layer; however, it implies energy expenditure. In this work, a two-step coating system was performed: anodizing in tartaric-sulphuric acid and a post-treatment with a Zr-based conversion coating, obtained at room temperature by immersion in hexafluorozirconic acid (H2ZrF6). To establish the best condition for coating formation on the aluminum oxide layer, different concentration and pH values of the H2ZrF6 solution were studied. Morphological and chemical analyses were performed respectively by SEM and EDS. The corrosion resistance evaluation was carried out by EIS in 0.5 M NaCl. Heterogeneity was observed in the obtained coatings. However, the samples treated with H2ZrF6 had a higher corrosion resistance than unsealed samples. The best concentration and pH range observed for the H2ZrF6 solution were 1 % and 3 to 3.5, respectively. Under these conditions, a greater corrosion resistance was evidenced in comparison to that obtained with boiling water sealing.

In this study, steel samples treated in a hexafluorozirconic acid based solution for different durations were investigated. X-ray photoelectron spectroscopy (XPS) revealed the existence of a zirconium oxide (ZrO2) layer on the treated steel. The increased contact angle of water on the treated steel with increased treatment duration indicated that the hexafluorozirconic acid treatment promoted the hydrophobicity of the surface. The corrosion results showed that the longer acid treatment gave rise to higher corrosion resistance of the treated steel in a 0.5 M NaCl solution by forming the better ZrO2 layer on the steel surface. The cathodic delamination of polyurethane coatings from the treated steel substrates was measured using a Scanning Kelvin Probe (SKP). The longer acid treatment resulted in significantly slower rate of cathodic delamination of the polyurethane coating due to the higher adhesion strength of the coating.

Hexafluorozirconic Acid, 45%, CAS 12021-95-3, (also known as hexafluorozirconic acid or Hexafluorozirconic acid) has the formula H2ZrF6. It is a corrosive chemical, like all salts of Hexafluorozirconic acid. Hexafluorozirconic acid finds use in zirconium oxide thin films for aluminum annodizing, in surface treatment applications, electroplating, and in chrome-free aluminum lacquering processes.  For metal treatment processes, Hexafluorozirconic acid and Fluorotitanic acid are often used together in the plating system.

Other release to the environment of this substance is likely to occur from: outdoor use in long-life materials with low release rate (e.g. metal, wooden and plastic construction and building materials) and indoor use in long-life materials with low release rate (e.g. flooring, furniture, toys, construction materials, curtains, foot-wear, leather products, paper and cardboard products, electronic equipment). This substance can be found in products with material based on: metal (e.g. cutlery, pots, toys, jewellery).

Hexafluorozirconic Acid Solution has multiple uses in inorganic chemical reactions such as titanium oxide photocatalysts and the preparation of zirconium oxide thin films. American Elements can manufacture most materials in high purity and ultra-high purity (up to 99.99999%) forms and conforms to current ASTM test standards; A range of grades are available, including

The Hexafluorozirconic acid is an organic compound with the formula H2ZrF6. The analysis is provided for the Hexafluorozirconic Acid international market including development history, Hexafluorozirconic Acid industry competitive landscape analysis. The composition also comprises hexafluorozirconic acid or salts thereof.

Most of the nanozirconia coating formulations are based on hexafluorozirconic acid solutions that may contain hexafluorosilicic acid indispensably. A new process has been developed to synthesize hexafluorozirconic acid in the powder form which is free from silica as indicated by the absence of Si peak in EDX spectrum. Nano-ceramic coating process is simplified by making up the bath solution using dry H2ZrF6 powder and polyacrylic acid. The powder form makes transportation easier. Hexafluorozirconic acid powder based nano zirconia (PNZ) coat was characterized by FESEM (field emission scanning electron microscopy), EDX (Energy-Dispersive X-ray Spectroscopy), XRD (X-ray diffraction) and XPS (X-ray photoelectron spectroscopy) studies. The PNZ coat formed on mild steel (MS) was characterized by linear polarization (LP) studies and Electrochemical Impedance Spectroscopy (EIS) and also compared with the commercial nano-zirconia coating chemical (Bonderite NT-1) treated mild steel. Polyester epoxy powder coat (PEP) was applied on powder based nano zirconia treated mild steel (PEP/PNZ), and commercially Bonderite NT-1 treated mild steel (PEP/NT). The dry film properties of the organic coat with the nanoceramic base coat were studied by neutral salt spray test, humidity resistance, impact resistance and adhesion tape tests as per ASTM (American Society for Testing and Materials) methods. The corrosion resistance and adhesion of PEP/PNZ coating system are comparable with the performance of PEP coated on the commercial nano zirconia coating solution (NT-1).

Our Hexafluorozirconic acid is a 40% aqueous solution with stable quality and low-level impurities

Synthesis and characterization of powder form of hexafluoro zirconic acid.

Convenient form of powder based nano-zirconia (PNZ) coating formulation and its corrosion resistance on mild steel.

Electrochemical corrosion studies of PNZ treated mild steel (MS) without organic top coat.

Comparison of polyester epoxy powder coat (PEP) on PNZ and commercial Bonderite NT-1 treated MS.



Used for:
• Hexafluorozirconic acid based surface pretreatments on steel for corrosion resistance
• Preparation of titania photocatalyst synthesized from ionic-liquid-like precursor
• Synthesis of fluoride-releasing dental monomer
• As precursor to ZrO2 ceramic thin films



Mil Spec (military grade), ACS, Reactive & Technical Grade, Food, Agricultural & Pharma Grade, Optical Grade, USP and EP / BP (European Pharmacopoeia / British Pharmacopoeia) In addition to special compositions for commercial and research applications and new proprietary technologies, on request We can also produce materials according to special specifications.

Typical and specialty packaging is available, as well as additional research, technical and safety (MSDS) data. For information on features, delivery time and pricing, please contact us above.The main use of zirconium is in dentistry as a refractory material as a protective coating on titanium dioxide pigment particles, as well as in the production of hard ceramics such as insulation, abrasives and enamels. .

Stabilized zirconia is used in oxygen sensors and fuel cell membranes because it has the ability to allow oxygen ions to move freely through the crystalline structure at high temperatures. This high ionic conductivity (and low electronic conductivity) makes it one of the most useful electro ceramics.

Zirconium dioxide is also used as a solid electrolyte in electrochromic devices.Zirconia is the precursor to electro ceramic lead zirconate titanate (PZT), the high K dielectric found in numerous components. It is a phosphate-free compound used in environmentally friendly metal surface coating chemicals. used before painting. It has an effect preventing corrosion and enhancing the adhesion of the paint to the surface.

Niche uses: The very low thermal conductivity of the cubic phase of zirconium has also led to its use as a thermal barrier coating or TBC to allow higher temperatures in jet and diesel engines. Thermodynamically, the higher the operating temperature of an engine, the higher the possible efficiency.

Another use of low thermal conductivity is a ceramic fiber insulation for crystal growth furnaces, fuel cell stack insulation and infrared heating systems.This material is also used in dentistry for dental restorations such as crowns and bridges coated with traditional feldspathic porcelain for aesthetic reasons or made entirely of monolithic zirconia. It is used in the manufacture of sub-frames for the construction of strong, extremely durable dental prostheses. , with a limited but constantly evolving aesthetic. Zirconia stabilized with yttria (yttrium oxide), known as zirconia stabilized with yttria, can be used as a strong base material in some all-ceramic crown restorations. Transform hardened zirconia is used in making ceramic knives. Due to its hardness, ceramic edged cutlery stays sharp longer than steel edged products. It was used as a component of sticks to be the center of attention due to its infusibility and brilliant shine in incandescent state.

Other release to the environment of this substance is likely to occur from: indoor use (e.g. machine wash liquids/detergents, automotive care products, paints and coating or adhesives, fragrances and air fresheners) and outdoor use resulting in inclusion into or onto a materials (e.g. binding agent in paints and coatings or adhesives).

Hexafluorozirconic Acid Solution has many uses in inorganic chemical reactions such as the preparation of titanium oxide photocatalysts and zirconium oxide thin films.

This substance is used in the following products: laboratory chemicals.

There is a growing interest in conversion coatings based on titanium and/or zirconium as the result of the health and environmental issues associated with legacy chromate and phosphate conversion coatings. Any alternative technology should be environmentally friendly and cost effective, and also able to achieve comparable corrosion resistance and paint adhesion for ferrous and non-ferrous substrates. Conversion coatings based on titanium or zirconium seem to fulfill many of these requirements and thus offer a great potential for further applications. This literature review summarizes the scientific results in this rapidly growing area of research. Following the description of composition of conversion bath and deposition mechanism, the effects of process parameters for conversion baths such as pH, temperature, immersion time and agitation are presented together with coating characteristics. The effects of the type of substrate and substrate pre-treatment are explored for the most-studied substrates: Al alloys, zinc-coated steels and steels. Properties such as composition, morphology and thickness are summarized. The corrosion performance of the conversion coatings is discussed, as well as adhesion of organic coatings and delamination mechanism for a full coating system including substrate/coating/top-coat.

Industrial, infrastructure, transportation, construction, consumer goods, etc. The metals used in the construction of products and facilities in most applications, including steels, are primarily selected from three groups: steels, zinc-plated (galvanized) steels, and aluminum alloys (AA). All of these materials require protection to prevent environmental degradation, and the most common approach to corrosion protection is a multi-layer coating system. Metal components are treated through a series of processes to create this coating system: cleaning, surface pretreatment, and application of organic coating layers, including primer and topcoat. Surface pretreatments include anodizing (for aluminum alloys) and conversion coatings, which is the focus of this review. Conversion coatings are created by immersing a component in a chemical bath and reacting the metal substrate with the components in the bath to form a layer that covers the surface. These layers provide some corrosion protection by acting as a barrier to the environment or releasing anti-corrosion species. But,


The most important conversion coatings used to protect ferrous and non-ferrous metal substrates from corrosion and to promote adhesion are chromate conversion coatings (CCCs) and phosphate coatings. CCCs are extremely protective against corrosion. They consist of a chromium oxide / hydroxide backbone containing Cr in the 3+ oxidation state and also contain compounds containing Cr in the 6+ oxidation state. The 2 - 5 Cr (VI) provides the self-healing property with the ability to reform a protective coating after it has been broken by a mechanical or chemical process. Self-healing in CCCs occurs when the Cr (VI) remaining in the coating is reduced to an insoluble Cr 3+ compound. Phosphate coatings are hard, continuous, insoluble and electrically non-conductive and are used in a wide range of applications in the automotive, agricultural and white goods industries. 6


Both CCCs and phosphating have some health, environmental, and energy disadvantages. Chromate compounds are toxic and carcinogenic. Their use poses a health hazard to workers and requires costly monitoring and disposal. 7 The use of hexavalent chromium is restricted in the European Union and the USA. 8, 9 Phosphate coatings cause different problems; Discharge from concentrated phosphate baths has a detrimental effect on groundwater resources due to eutrophication in freshwater lakes and reservoirs. 10 Therefore, the use of phosphorus is also limited by environmental regulations. Also, phosphating baths operate at 30 to 99 ° C, typically about 50 ° C, above room temperature requiring energy input. 11 Finally, phosphating baths produce large amounts of sludge containing metal ions that require frequent sludge removal to maintain the optimum bath process. As a result of these problems, phosphate conversion coatings are increasingly being changed and alternatives are constantly being sought.


Environmental legislation and health issues have motivated a large number of studies devoted to potential alternatives for chromate and phosphate technology over the past two decades. The aim is to find a technology that is ecologically acceptable, harmless to human health, operating at lower energy costs, producing less discharge with low amounts of heavy or regulated metal ions (Zn, Ni, Mn) and still providing similarly comparable efficiency. Corrosion resistance and paint adhesion for ferrous and non-ferrous metal surfaces. These demands are not easy to fulfill, and potential alternatives explored in the literature include a wide variety of chemistries, including molybdate, permanganate, refractory metal oxyfluorides, phosphates, plasma coatings, sol-gel coatings, self-assembly layers, conductive polymers, inhibitors. only a few have reached the maturity of final commercial use in the industry, and the most important are titanium and / or zirconium-based conversion coatings that are the subject of the current review.


In the late 1980s and 1990s, several patents 19-21 were published describing the deposition of Ti and Zr-based conversion coatings from Hexafluoro-titanate and -zirconate solutions, leading to commercial products. The conversion and deposition processes from these baths are fast, contain little or no phosphate or heavy metals, and the coatings are thin and generally colorless. Aluminum and aluminum alloy surfaces have always been the focus of these studies in order to replace the old chromate or phosphate coatings. Between 2005 and 2015, interest in galvanized steel surfaces has intensified. It seems that the focus has been on the protection of steels in the last few years, and the number of studies on Al alloys has almost reached there. According to numerous patents, for example, the first generation of 22 - 26Zr conversion coatings was introduced to the automobile industry in 2005. 27, 28 Ti and Zr coatings are significantly higher than CCCs, and especially phosphate coatings. it is thin. Significant operational cost savings (30%) have been achieved compared to zinc phosphate coatings without compromising corrosion resistance or paint adhesion. 28 The performance of the first generation was similar for non-ferrous metal substrates, but not for ferrous materials, ie cold rolled steel. Second generation Zr coatings, 2.5 times thicker than the first generation, were launched in 2010 and also achieved comparable performance for cold rolled steel surfaces. 28


The review is organized into ten subsections. Following the description of the composition of the conversion baths and a general deposition mechanism, the process parameters for the conversion baths, ie pH, temperature, dipping time and agitation, are presented with their effects on coating properties. The effect of substrate on coating formation has been investigated for the three most studied substrates: alloys, galvanized steel and steels. Surface pretreatment and surface chemistry are critical parameters in conversion and deposition processes. Properties of conversion coatings are disclosed, including composition, morphology, and thickness. The corrosion performance of the conversion coating is discussed separately for each type of substrate, the adhesion of organic coatings when fully coated, and the mechanism of delamination (substrate / coating / top coat). This literature review primarily takes into account published scientific results in order to review the data and information collected so far and point out issues that need further research.

Zirconia was proposed to electrolyze carbon monoxide and oxygen from the Martian atmosphere to provide both fuel and oxidizer that could be used as a chemical energy storage for use in surface transportation on Mars. Carbon monoxide / Since oxygen engines can be produced by zirconium electrolysis with both carbon monoxide and oxygen, zirconium electrolysis, without the need for any water source to obtain hydrogen, they were proposed for early surface transportation use. hydrogen-based fuels. Zirconia can be used as a photocatalyst as the high band gap (~ 5 eV) allows the formation of high energy electrons and holes. Some studies have demonstrated the activity of doped zirconia (to increase visible light absorption) in reducing organic compounds and Cr (VI) from wastewater.

Zirconia is also a potential high-k dielectric material with potential applications as an insulator in transistors. Zirconia is also used in depositing optical coatings; Due to its low absorption in this spectral region, it is a high index material that can be used up to UV and middle IR. It is typically deposited by the PVD in such applications. Some watch cases in jewelery are advertised as "black zirconium oxide". In 2015, Omega released a full ZrO2 watch called "The Dark Side of The Moon" with a ceramic case, bezel, buttons and buckle, and this watch is four times harder than stainless steel and therefore much more resistant to scratches during daily use. announced.

Structure: Three stages are known: monoclinic below 1170 ° C, tetragonal between 1170 ° C and 2370 ° C, and cubic above 2370 ° C. The trend is for higher symmetry at higher temperatures, as is usually the case. A small percentage of calcium or yttrium oxides stabilize in the cubic phase. The very rare tazheranite mineral (Zr, Ti, Ca) O2 is cubic. Unlike TiO2, which contains six-coordinated titanium in all stages, monoclinic zirconium consists of a

seven-coordinated zirconium center. This difference is attributed to the larger size of the zirconium atom than the titanium atom.

Chemical reactions: Zirconia is chemically unresponsive. It is gradually attacked by concentrated hydrofluoric acid and sulfuric acid. When heated with carbon, it turns into zirconium carbide. When heated with carbon in the presence of chlorine, it turns into zirconium tetrachloride. This conversion forms the basis for the purification of zirconium metal and is similar to the Kroll process.

Engineering properties: Zirconium dioxide is one of the most studied ceramic materials. ZrO2 adopts a monoclinic crystal structure at room temperature and becomes tetragonal and cubic at higher temperatures. The change in volume caused by the transition of the structure from tetragonal to monoclinic causes large stresses and causes cracking after cooling from high temperatures. When zirconia is mixed with some other oxides, tetragonal and / or cubic phases are stabilized. Effective additives include magnesium oxide (MgO), yttrium oxide (Y2O3, yttria), calcium oxide (CaO) and cerium (III) oxide (Ce2O3). Zirconia is generally more useful in the phase 'stabilized' state. After heating, zirconia undergoes disruptive phase changes.

By adding small percentages of yttria, these phase changes are eliminated and the resulting material has superior thermal, mechanical and electrical properties. In some cases, the tetragonal phase may be metastable. If sufficient quantities of metastable tetragonal phase are present, an applied stress amplified by the stress concentration at a crack tip can cause the tetragonal phase to transform into monoclinic with the associated volume expansion.

This phase transformation can then compress the crack, delay its growth and increase fracture toughness. This mechanism is known as conversion hardening and significantly extends the reliability and longevity of products made with stabilized zirconia. The ZrO2 band gap depends on phase (cubic, tetragonal, monoclinic or amorphous) and preparation methods with typical estimates of 5--7eV. A particular case of zirconia is tetragonal zirconia polycrystalline or TZP, which is indicative of polycrystalline zirconium consisting only of metastable tetragonal phase.

Hexafluorozirconic Acid Usage: Acid and its salts are used in metal surface technology.

Hexafluorozirconic Acid Safety Instructions: The acid is toxic in case of contact with skin, ingestion or inhalation. Causes severe skin burns. Causes serious damage to eyes. Decomposition produces hydrogen fluoride and zirconium oxides. Strong bases, acids and oxidizing agents cause violent reactions with the acid.


Release to the environment of this substance can occur from industrial use: manufacturing of the substance


Hexafluorozirconic Acid Properties:

Molar mass 207.22 g mol - 1

Physical state: liquid

Density: 1.51 g cm - 3 

Solubility: Miscible with water.

IUPAC names:

Dihydrogen hexafluorozirconate(2-)

dihydrogen hexafluorozirconate(2-)

Dihydrogen hexafluorozirconate(2-)

dihydrogen hexafluorozirconiumdiuide


Hexafluorozirconic acid


Other identifiers:


CAS number:






  • Share !