Zinc Acetylacetonate Hydrate Description
This coordination compound comprises zinc(II) ions that are chelated by two bidentate acetylacetonate (acac) ligands, forming a tetrahedral geometry. The hydrate (usually x = 1–2) displays variable water content, resulting in colourless to white monoclinic crystals. It is moisture‐sensitive and undergoes hydrolysis in humid air, thereby releasing acetylacetone. The anhydrous substance has a molecular weight of 263.62 g/mol and decomposes at 138–142 °C without melting. Its density is between 1.42 and 1.45 g/cm³.
Thermogravimetric analysis (TGA) indicates weight loss at approximately 100 °C due to dehydration and at 250–300 °C owing to ligand decomposition. Its volatility under reduced pressure supports applications in the vapour phase. The compound is highly soluble in organic solvents such as ethanol (25 g/100 mL), acetone and chloroform, while it is insoluble in water. In solution, it emits faint luminescence and decomposes following extended exposure to ultraviolet irradiation.
The acac ligands undergo electrophilic substitution and readily coordinate with other metals. Under inert conditions, the compound remains thermally stable up to 120 °C. However, it reacts with strong acids or bases, releasing acetylacetone (pKa = 8.9). The Lewis acidic property permits its use as a catalyst in organic reactions.
Zinc Acetylacetonate Hydrate Applications
Zinc acetylacetonate hydrate is employed predominantly as a high-purity precursor for zinc oxide thin films in chemical vapour deposition (CVD) and atomic layer deposition (ALD) procedures, which are applied in the fabrication of transparent conductive oxides for solar cells, touchscreens and energy-efficient windows. Its volatility and controlled decomposition permit uniform film growth for piezoelectric sensors and ultraviolet-emitting devices. Additionally, the compound is utilised as a Lewis acid catalyst in organic synthesis, facilitating transesterification reactions for biodiesel production and ring-opening polymerisations. In materials science, the compound is used as a cross-linking agent for silicone rubbers and resins via ligand-exchange mechanisms, and as a template for sol–gel synthesis of zinc oxide nanoparticles for photocatalysis and antibacterial coatings. Other applications include doping semiconductor materials such as titanium dioxide, increasing flame retardancy in polymers and stabilising UV-sensitive coatings. Given its moisture sensitivity, processing is carried out under an inert atmosphere, particularly in vapour-phase applications where precise stoichiometry is required.
Zinc Acetylacetonate Hydrate Packaging
Our products are packaged in customised cartons of various sizes according to the material dimensions. Small items are packed in polypropylene boxes, while larger items are placed in custom wooden crates. Packaging is executed in accordance with specified requirements and employs appropriate cushioning materials to protect the items during transportation.
Packaging: Carton, Wooden Box, or Customized.
Please refer to the packaging details provided for further information.
Manufacturing Process
1. Testing Method
(1) Chemical Composition Analysis – Verified using techniques such as GDMS or XRF to confirm compliance with purity requirements.
(2) Mechanical Properties Testing – Includes tests of tensile strength, yield strength and elongation to assess material performance.
(3) Dimensional Inspection – Measures thickness, width and length to ensure adherence to specified tolerances.
(4) Surface Quality Inspection – Checks for defects such as scratches, cracks or inclusions by means of visual and ultrasonic examination.
(5) Hardness Testing – Determines material hardness to confirm uniformity and mechanical reliability.
Please refer to the SAM testing procedures for further details.
Zinc Acetylacetonate Hydrate FAQs
Q1. What are the primary industrial uses of this compound?
The principal application is as a vapour deposition precursor for zinc oxide films in optoelectronic devices, including solar cells and transparent electrodes, and in piezoelectric devices. The compound operates at temperatures of 130–150 °C under reduced pressure and is used owing to its defined stoichiometry.
Q2. Why is it preferred in catalysis?
The compound is used as a Lewis acid catalyst. It activates carbonyl groups in esterification and transesterification reactions (for example, biodiesel synthesis) with its bidentate acetylacetonate ligands facilitating controlled reactivity in polymerisations.
Q3. How does moisture affect its performance?
The hydrate is hygroscopic and decomposes above 140 °C. For moisture-sensitive applications such as CVD, anhydrous grades are recommended; for solution-phase processes, for instance in sol–gel nanoparticle synthesis, the hydrate dissolves sufficiently in ethanol or chloroform.
Related Information
1. Common Preparation Methods
The synthesis of zinc acetylacetonate hydrate typically proceeds via a metathesis reaction between zinc salts and acetylacetone under controlled conditions. Industrially, zinc sulphate or zinc acetate is dissolved in a warmed ethanol–water mixture (typically 3:1 v/v) at 60–65 °C, followed by the dropwise addition of acetylacetone pre-mixed with stoichiometric ammonia as a deprotonating agent. The ammonia neutralises H⁺ ions released during complex formation, thereby driving the reaction towards completion. As the mixture cools to room temperature over 2–3 hours, white crystalline solids precipitate. The crude product is subsequently purified by recrystallisation from anhydrous ethanol, with slow evaporation at 35–40 °C yielding monoclinic crystals. Critical process controls include maintaining a pH of 7.5–8.0 to prevent co-precipitation of zinc hydroxide, using degassed solvents to minimise carbonate contamination, and ensuring a cooling rate below 5 °C/min to secure appropriate hydrate formation (x = 1–2). Final drying is performed under dynamic vacuum (<0.1 mbar) at 40 °C for 12 hours, achieving a yield of 70–85% with purity above 99%, as verified by chelatometric titration. The hydrate structure is established through the incorporation of water molecules into crystal lattice vacancies during crystallisation rather than by direct coordination to zinc centres.
Converters & Calculators
