New cover in Advanced Materials Technologies

The article is entitled ‘High-Throughput Screening of REBCO Superconducting Thin Films Fabricated Via Combinatorial Inkjet Printing and TLAG Process‘ and is published in the journal Advanced Materials Technologies

A new cover of an article has been published in the journal Advanced Materials Technologies, by researchers at ICMAB’s SUMAN research group with collegues from the ALBA Synchrotron, the Kyushu University and the ICN2. The article proposes a method to fabricate REBCO (Rare Earth Barium Copper Oxide) superconducting thin films by a combination of inkjet printing and the TLAG process (an ultrafast, non-equilibrium growth method).

The inkjet Printing

Researchers used a drop-on-demand piezoelectric inkjet printer (IJP) to fabricate combinatorial samples on (001) single-crystal STO (strontium titanium oxides) substrates. Prior to deposition, the substrates were thermally treated at 900ºC for 5 h to develop a flat terraced surface. Then, they used a multi-nozzle head to load each solution into separate nozzles; in this work, only two nozzles are involved in printing the combinatorial gradient: the first containing the precursor solution of YBCO (Yttrium), and the second GdBCO (Gadolinium). 

The TLAG method

After depositing the precursor solution onto the substrate, the sample undergoes a pyrolysis treatment. This step removes the organic components from the layer, converting it into a nanocrystalline thin film composed of BaCO₃, CuO and RE₂O₃.  They heated this film to 500ºC at a rate of 3-5 ºC/min followed by cooling to room temperature. Although commonly referred to as a pyrolytic process due to the removal of organic material, it is technically a thermo-oxidative decomposition, as it is carried out in the presence of an oxygen flow of 0,12 L/min.

Once the pyrolysis step is completed, the sample is ready to undergo the Transient Liquid Assisted Growth process to convert the nanocrystalline precursor layer in a REBCO epitaxial film.

The TLAG process is based on the formation of a Ba-Cu-O melt. To generate the melt, the required temperature and oxygen pressure conditions are established in two different steps. First, the sample is heated under low-pressure conditions to promote the reaction between BaCO₃ and CuO releasing CO₂ and  and forming the intermediate BaCu₂O₂ phase. Once this transformation is complete, a step-like increase in oxygen pressure is applied to rapidly shift the system within the Ba-Cu-O phase diagram into the regime where a transient liquid melt is generated.

Characterizing the samples

Once the samples were characterized,  they were characterized by the researchers. They did so by the use of several different techniques: Interferometry, Energy Dispersive X-ray Spectroscopy (EDX), X-ray diffraction (XRD), Scanning Hall Probe Microscopy (SHPM) and Microscopy. It was the combination of these scanning characterization methods that were employed to evaluate the local properties of the sample, that enabled the researchers to construct of a quantitative property map for each parameter.

What is the relevance of this study?

 In the words of the researchers, “This work presents a high-throughput strategy to accelerate the development of REBCO superconducting thin films by combining combinatorial synthesis, automated characterization, and data-driven analysis in a single workflow. Using drop-on-demand inkjet printing, we fabricated compositional gradient samples that allow us to systematically study how Rare Earth composition influences the TLAG growth process and the final superconducting properties.”

“By combining advanced characterization techniques, including energy-dispersive X-ray spectroscopy, synchrotron-based diffraction, scanning Hall probe microscopy, and electron microscopy, we built detailed property maps that help uncover the relationship between composition, crystal growth, and superconducting performance. Beyond REBCO superconductors, the workflow developed in this study can be extended to other complex oxide thin films and advanced functional materials, providing a powerful route for faster materials discovery and optimization.“, they added.

Abstract

High-throughput screening has revolutionized material design, enabling the accelerated development and optimization of materials through data-driven approaches. This study employs drop-on-demand inkjet printing to fabricate combinatorial superconducting REBa₂Cu₃O_7-d(REBCO, RE=Y_xGd_1-x) thin films with a controlled compositional gradient, allowing a systematic investigation of Rare Earth composition effects on the Transient Liquid Assisted Growth (TLAG) process. A methodological framework is established for fabricating and characterizing combinatorial REBCO thin films. Automated and synchrotron-based techniques—including Interferometry, EDX, XRD, and Scanning Hall Probe Microscopy (SHPM)—are used to build comprehensive property maps, revealing composition-driven variations in crystal growth and superconducting properties. Furthermore, SEM and STEM confirm REBCO crystal quality and provide deeper material insights at specific combinatorial sample locations. This framework also lays the groundwork for integrating machine learning approaches into the understanding of the TLAG process and predicting the final quality of REBCO superconductive thin films. By bridging combinatorial synthesis, advanced characterization, and data-driven analysis, this study establishes a workflow that can be leveraged in the future to facilitate the scaling-up of TLAG technology for industrial applications.

Reference

High-Throughput Screening of REBCO Superconducting Thin Films Fabricated Via Combinatorial Inkjet Printing and TLAG Process
Emma Ghiara, Zeyu Wu, Mahel Voulhoux, Ona Mola Bertran, Vittorio Bertini, Carla Torres, Aiswarya Kethamkuzhi, Guilherme Theophilo Telles, Victor Fuentes, Elzbieta Pach, Cornelia Pop, Eduardo Solano, Kapil Gupta, Takanobu Kiss, Xavier Obradors, Teresa Puig
Advanced Materials Technologies, 2026; 11:e02441
DOI: 10.1002/admt.202502441