Additive manufacturing of Zn with submicron resolution and its conversion into Zn/ZnO core-shell structures

Area of Science:

• Materials Science
• Additive Manufacturing
• Electrochemistry

Background:

• Electrohydrodynamic redox 3D printing (EHD-RP) is an advanced additive manufacturing technique.
• EHD-RP offers submicron resolution and multi-metal deposition capabilities.
• Current EHD-RP methods are limited to depositing only copper (Cu) and silver (Ag).

Purpose of the Study:

• To expand the range of metals that can be deposited using EHD-RP.
• To investigate the use of aqueous solvents as an alternative to organic solvents in EHD-RP.
• To demonstrate the deposition and conversion of novel metal structures using EHD-RP.

Main Methods:

• Utilized acidic aqueous solvents for EHD-RP instead of traditional organic solvents.
• Demonstrated the deposition of copper (Cu) and zinc (Zn) from sacrificial anodes.
• Employed mass spectrometry to analyze the purity of deposited Zn.
• Investigated the conversion of deposited Zn structures into zinc oxide (ZnO) via thermal oxidation.

Main Results:

• Successfully deposited Cu and Zn using aqueous solvents in EHD-RP.
• Confirmed the importance of solvent choice for achieving pure Zn deposition via mass spectrometry.
• Created Zn structures with a width of 250 nm.
• Partially converted deposited Zn structures into semiconducting ZnO by oxidation at 325 °C.

Conclusions:

• Aqueous solvents are viable for EHD-RP, broadening the accessible material palette beyond Cu and Ag.
• The study successfully demonstrated the deposition of Zn and its subsequent conversion to ZnO, opening avenues for new material synthesis.
• This research significantly advances the capabilities of small-scale additive manufacturing for diverse metal and metal oxide structures.