Banca de QUALIFICAÇÃO: FERNANDO TAKASHI DA ROCHA ARITA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : FERNANDO TAKASHI DA ROCHA ARITA
DATE: 07/03/2024
TIME: 14:00
LOCAL: Híbrido - Santo André
TITLE:

Metal Oxide Thin Films for Stable and Efficient Inverted Perovskite Solar Cells

PAGES: 74
BIG AREA: Engenharias
AREA: Engenharia de Materiais e Metalúrgica
SUMMARY:

Effects of Global climate change have been increasingly more evident in the last few decades, promoting research in sustainable sources of energy more efficiently. Perovskite solar cells have stood out as a promising photovoltaic device, as its efficiency rapidly increased, reaching values close to silicon-based commercial devices. The main obstacle for its commercialization is the stability of the perovskite layer when facing ambient elements, especially humidity. This problem can be addressed by modifying the perovskite composition or by changing the material of adjacent layers. This work focuses on the deposition of metal oxide thin films as hole transport layer (HTL) in inverted perovskite solar cells (IPSC). Mixed copper oxide thin films were deposited using reactive RF-sputtering and copper-based delafossite thin films were produced by reactive RF-sputtering followed by an annealing process and by spin-coating from a suspension of synthesized nanoparticles. These films were experimentally characterized to determine optoelectronic properties that were input in numerical simulations to determine their performance as HTL in IPSC. From the copper oxide series, single phase Cu₂O, CuO and an intermediate phase Cu₄O₃ were deposited, presenting properties in accordance with literature. However, hall effect measurements revealed Cu₄O₃ as an efficient hole transporter with a hall mobility of 102.8 cm².V^-1s^-1, twenty times greater than the other two copper oxides.  For this reason, this material excelled the device’s simulated power conversion efficiency, when compared to other copper oxides and the well-established HTL, PEDOT:PSS. From the sputtered delafossite series, single phase thin films were produced with an annealing process at 900°C under an argon atmosphere. The use of a reducing atmosphere decreased the temperature for the delafossite formation, when compared to its formation in ambient conditions (1100ºC). Finally, copper aluminate, copper chromate and mixed copper aluminum-chromate nanoparticles were successfully synthesized by the Pechini Method. Delafossite thin films were deposited from suspensions of ball-milled nanoparticles and their thickness can be controlled by suspension’s concentration and by the deposition rotation speed. Delafossite thin films need to be further characterized to determine how well it would perform as HTLs, although initial characterizations are promising.

COMMITTEE MEMBERS:
Presidente - Interno ao Programa - 1545738 - MARCIA TSUYAMA ESCOTE
Membro Titular - Examinador(a) Interno ao Programa - 1305186 - SERGIO BROCHSZTAIN
Membro Titular - Examinador(a) Interno ao Programa - 1734912 - ROOSEVELT DROPPA JUNIOR
Membro Titular - Examinador(a) Externo à Instituição - LÍDIA CARVALHO GOMES - UFPE
Membro Suplente - Examinador(a) Interno ao Programa - 1669182 - JOSE FERNANDO QUEIRUGA REY
Membro Suplente - Examinador(a) Interno ao Programa - 052.991.506-52 - JULIANA DA SILVA BERNARDES - UFABC
Membro Suplente - Examinador(a) Interno ao Programa - 1545089 - DANIEL ZANETTI DE FLORIO
Membro Suplente - Examinador(a) Externo à Instituição - DANIELE CRISTINA FERREIRA