Banca de QUALIFICAÇÃO: RAYSSA RIBEIRO RODRIGUES

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : RAYSSA RIBEIRO RODRIGUES
DATE: 27/02/2025
TIME: 08:30
LOCAL: Auditório do Laboratório de Cimentos da UFRN
TITLE:

Formulation of Functional Nanometric TiNb₂O₇ Inks for 3D Printing of Electrodes for Lithium-Ion Batteries

KEY WORDS:

3D Printing; nanometric Inks; TiNb₂O₇; electrode; synthesis.

PAGES: 80
BIG AREA: Engenharias
AREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Materiais Não-Metálicos
SPECIALTY: Cerâmicos
SUMMARY:

The search for new battery materials has intensified to enhance efficiency, storage capacity, and device compactness. Among the promising anode materials, TiNb₂O₇ (NTO) stands out due to its high theoretical capacity (~388 mAh g⁻¹), which corresponds to the maximum charge that can be stored per gram of material during charge and discharge cycles. Additionally, NTO exhibits high cycling stability, meaning it can maintain its performance over multiple cycles, which is crucial for battery durability. However, material selection is not the only critical factor influencing battery performance; manufacturing methods also play a fundamental role. Although significant advances have been achieved in recent decades, the modernization of manufacturing techniques remains underexplored due to the limitations of conventional methods. In this context, 3D printing, or additive manufacturing, emerges as an innovative approach for fabricating battery components, enabling the creation of optimized electrodes with increased surface area and improved electrochemical performance. Among the various 3D printing techniques, Direct Ink Writing (DIW) stands out, where ink formulation is a key factor in ensuring optimal printing characteristics. The scarcity of information on these formulations highlights the need for further research in this area. Therefore, this study proposes the development of an electrically active and functional nanometric ink for DIW based production of lithium-ion battery electrodes, making the process measurable, ensuring good printability, and preserving the structural integrity of the piece after sintering. To achieve this, the resin will incorporate synthesized powder as one of its components. Two synthesis routes were employed, hydrothermal and Pechini, to produce NTO and compare their results. After synthesis, the material was calcined, and the resulting powder was used to prepare the inks for 3D printing. The printed samples were initially evaluated dimensionally and then subjected to sintering. Subsequently, structural and morphological characterizations were performed, including X-ray Diffraction (XRD) and Field Emission Scanning Electron Microscopy (SEM-FEG). Additionally, thermal analyses such as thermogravimetry (TG) and differential scanning calorimetry (DSC) were conducted, along with electrochemical analyses to investigate the material’s performance. The results demonstrated that it was possible to synthesize NTO using the proposed methods and successfully produce nanometric inks utilizing an adapted bioprinter to fabricate electrically active mini-electrodes. The formulated resin, composed of a polyvinyl alcohol (PVA) and alcohol-based solution, exhibited good printability and maintained dimensional stability of the printed structures.

COMMITTEE MEMBERS:
Presidente - 1298936 - ANTONIO EDUARDO MARTINELLI
Interno - 1300987 - CARLOS ALBERTO PASKOCIMAS
Externo à Instituição - ARMANDO MONTE MENDES - UFRN