A Study of the Preparation and Properties of Antioxidative Copper Inks with High Electrical Conductivity

Abstract

Conductive ink using copper nanoparticles has attracted much attention in the printed electronics industry because of its low cost and high electrical conductivity. However, the problem of easy oxidation under heat and humidity conditions for copper material limits the wide applications. In this study, antioxidative copper inks were prepared by dispersing the nanoparticles in the solution, and then conductive copper films can be obtained after calcining the copper ink at 250 °C in nitrogen atmosphere for 30 min. A low sheet resistance of 47.6 mΩ/□ for the copper film was measured by using the four-point probe method. Importantly, we experimentally demonstrate that the electrical conductivity of copper films can be improved by increasing the calcination temperature. In addition, these highly conductive copper films can be placed in an atmospheric environment for more than 6 months without the oxidation phenomenon, which was verified by energy-dispersive X-ray spectroscopy (EDS). These observations strongly show that our conductive copper ink features high antioxidant properties and long-term stability and has a great potential for many printed electronics applications, such as flexible display systems, sensors, photovoltaic cells, and radio frequency identification.

Understanding the Importance of Cu(I) Intermediates in Self-Reducing Molecular Inks for Flexible Electronics

“…Motivated by the substantial cost reduction, a shift in research focus from silver to copper metal inks can be easily understood from this economical, industry-driven context. Conventionally, metal inks are particle-based, which means the metal is already present in its reduced state, dispersed in a solvent blend and surrounded by capping agents, dispersants, surfactants, … This proven concept allows for the deposition of both silver and copper layers, using a wide variety of sintering/curing techniques [1][2][3]. Recently, the dawn of a second class of metal inks was witnessed, based on coordinated metal ions in solution containing ligands with a double function: stabilizing the metal ions in solution and acting as reductants during the precursor's decomposition.…”

Synthesis and Characterization of Pure Copper Nanostructures Using Wood Inherent Architecture as a Natural Template

“…Silver and gold have attracted particularly great interest given their unique plasmon resonance and high stability. However, the high cost of silver and gold limits their wide industrial application [ 2 ]. Because copper is much cheaper and more abundant, copper nanoparticles (Cu NPs) may be considered a replacement for silver and gold NPs.…”

Comparative environmental fate and toxicity of copper nanomaterials

“…It is estimated that only a few hundred tons of the total production were converted to Cu-based nanoparticles (Cu NPs) , despite there being many emerging applications for nano-Cu materials. Many applications involve the traditional role of Cu as a conductor, such as conductive dyes (Albrecht et al, 2016;Hokita et al, 2015;Tam and Ng, 2015;Kharisov and Kharissova, 2010;Tsai et al, 2015;Gopalan et al, 2016) or heat transfer fluids (Park et al, 2015;Montes et al, 2015;Azizi et al, 2016;Rizwan-ul-Haq et al, 2016), but the use of nano-Cu is rapidly expanding into novel applications such as catalysts in organic synthesis (Dugal and Mascarenhas, 2015;Lennox et al, 2016;Barot et al, 2016), sensors (Albrecht et al, 2016;Tsai et al, 2015;Gopalan et al, 2016;Brahman et al, 2016;Pourbeyram and Mehdizadeh, 2016), solar cells (Yoon et al, 2010;Parveen et al, 2016;Shen et al, 2016), light-emitting diodes , hydrogen generation (Liu et al, 2015a;Liu et al, 2015b), and drug delivery (Woźniak-Budych et al, 2016). Based on the antifungal and antimicrobial properties of Cu + 2 , Cu NPs are actively being developed for applications in agriculture and food preservation (Park et al, 2015;Montes et al, 2015;Dugal and Mascarenhas, 2015;Ray et al, 2015;Kalatehjari et al, 2015;Ponmurugan et al, 2016;Maniprasad et al, 2015;Majumder and Neogi, 2016;Villanueva et al, 2016), textiles …”