Advances in Dielectric Thin Films for Energy Storage Applications, Revealing the Promise of Group IV Binary Oxides

• Published in: ACS energy letters 2021-06, Vol.6 (6), p.2208-2217
• Main Authors: Silva, José P. B, Sekhar, Koppole C, Pan, Hao, MacManus-Driscoll, Judith L, Pereira, Mário
• Format: Article
• Language: English
• ISSN: 2380-8195; 2380-8195
• DOI: 10.1021/acsenergylett.1c00313

Among currently available energy storage (ES) devices, dielectric capacitors are optimal systems owing to their having the highest power density, high operating voltages, and a long lifetime. Standard high-performance ferroelectric-based ES devices are formed of complex-composition perovskites and require precision, high-temperature thin-film fabrication. The discovery of ferroelectricity in doped HfO2 in 2011 at the nanoscale was potentially game-changing for many modern technologies, such as field effect transistors, non-volatile memory, and ferroelectric tunnel junctions. This is because HfO2 is a well-established material in the semiconductor industry, where it is used as a gate dielectric. On the other hand, (pseudo)​binary HfO2 and ZrO2-based materials have received much less attention for ES capacitors, even though antiferroelectric HfO2 and ZrO2-based thin films show strong promise. This Focus Review summarizes the current status of conventional polymer and perovskite ferroic-based ES. It then discusses recent developments in, and proposes new directions for, antiferroelectric and ferroelectric group IV oxides, namely HfO2 and ZrO2-based thin films.