Australian Nuclear Science & Technology Organisation

The remarkable proton and oxide-ion (dual-ion) conductivities of hexagonal perovskite-related oxide Ba7Nb3.8Mo1.2O20.1 are promising for next-generation electrochemical devices. The unique ion-transport mechanisms they unveiled will hopefully pave the way for better dual-ion conductors, which could play an essential role in tomorrow's clean energy technologies. The remarkable proton and oxide-ion (dual-ion) conductivities of hexagonal perovskite-related oxide Ba7Nb3.8Mo1.2O20.1 are promising for next-generation electrochemical devices, as reported by scientists at Tokyo Tech. The unique ion-transport mechanisms they unveiled will hopefully pave the way for better dual-ion conductors, which could play an essential role in tomorrow's clean energy technologies. Clean energy technologies are the cornerstone of sustainable societies, and solid-oxide fuel cells (SOFCs) and proton ceramic fuel cells (PCFCs) are among the most promising types of electrochemical devices for green power generation. These devices, however, still face challenges that hinder their development and adoption. Ideally, SOFCs should be operated at low temperatures to prevent unwanted chemical reactions from degrading their constituent materials. Unfortunately, most known oxide-ion conductors, a key component of SOFCs, only exhibit decent ionic conductivity at elevated temperatures. As for PCFCs, not only are they chemically unstable under carbon dioxide atmospheres, but they also require energy-intensive, high-temperature processing steps during manufacture. Fortunately, there is a type of material that can solve these problems by combining the benefits of both SOFCs and PCFCs: dual-ion conductors. By supporting the diffusion of both protons and oxide ions, dual-ion conductors can realize high total conductivity at lower temperatures and improve the performance of electrochemical devices. Although some perovskite-related dual-ion conducting materials such as Ba7Nb4MoO20 have been reported, their conductivities are not high enough for practical applications, and their underlying conducting mechanisms are not well understood. Against this backdrop, a research team led by Professor Masatomo Yashima from Tokyo Institute of Technology, Japan, decided to investigate the conductivity of materials similar to 7Nb4MoO20 but with a higher Mo fraction (that is, Ba7Nb4-xMo1+xO20+x/2). Their latest study, which was conducted in collaboration with the Australian Nuclear Science and Technology Organisation (ANSTO), the High Energy Accelerator Research Organization (KEK), and Tohoku University, was published in Chemistry of Materials. After screening various Ba7Nb4-xMo1+xO20+x/2 compositions, the team found that Ba7Nb3.8Mo1.2O20.1 had remarkable proton and oxide-ion conductivities. "Ba7Nb3.8Mo1.2O20.1 exhibited bulk conductivities of 11 mS/cm at 537 ℃ under wet air and 10 mS/cm at 593 ℃ under dry air. Total direct current conductivity at 400 ℃ in wet air of Ba7Nb3.8Mo1.2O20.1 was 13 times higher than that of Ba7Nb4MoO20, and the bulk conductivity in dry air at 306 ℃ is 175 times higher than that of the conventional yttria-stabilized zirconia (YSZ)," highlights Prof. Yashima. Next, the researchers sought to shed light on the underlying mechanisms behind these high conductivity values. To this end, they conducted ab initio molecular dynamics (AIMD) simulations, neutron diffraction experiments, and neutron scattering length density analyses. These techniques enabled them to study the structure of Ba7Nb3.8Mo1.2O20.1 in greater detail and determine what makes it special as a dual-ion conductor. Interestingly, the team found that the high oxide-ion conductivity of Ba7Nb3.8Mo1.2O20.1 originates from a unique phenomenon. It turns out that adjacent MO5 monomers in Ba7Nb3.8Mo1.2O20.1 can form M2O9 dimers by sharing an oxygen atom on one of their corners (M = Nb or Mo cation). The breaking and reforming of these dimers gives rise to ultrafast oxide-ion movement in a manner analogous to a long line of people relaying buckets of water (oxide ions) from one person to the next. Furthermore, the AIMD simulations revealed that the observed high proton conduction was due to efficient proton migration in the hexagonal close-packed BaO3 layers in the material. Taken together, the results of this study highlight the potential of perovskite-related dual-ion conductors and could serve as guidelines for the rational design of these materials. "The present findings of high conductivities and unique ion migration mechanisms in Ba7Nb3.8Mo1.2O20.1 will help the development of science and engineering of oxide-ion, proton, and dual-ion conductors," concludes a hopeful Prof. Yashima.

CAMBRIDGE, Mass. & BRISBANE, Australia--(BUSINESS WIRE)-- Vaxxas, a clinical-stage biotechnology company commercializing a novel vaccination platform, today announced another key addition to its executive leadership team with the appointment of Doug Cubbin as Chief Financial Officer. Doug joins Vaxxas as the company experiences significant growth and advances toward commercialization of its high-density microarray patch (HD-MAP) vaccine delivery technology. This press release features multimedia. View the full release here: Vaxxas CFO Doug Cubbin (Photo: Business Wire) A highly qualified executive leader, Doug has more than 30 years’ experience in finance, M&A, and business development. Most recently, Doug was the Group Chief Financial Officer at Telix Pharmaceuticals Limited, a global ASX 200 biopharmaceutical company focused on the development and commercialization of diagnostic and therapeutic products. During his tenure at Telix, Doug helped grow the market capitalization of the business to AU$2.3 billion (US$1.6 billion) and built a global finance team. He was also a key member of the team who successfully completed the Telix IPO, and subsequent capital raises, with a total of AU$270 million (US$180 million) raised. During Doug’s time with Telix, the company made four acquisitions. Prior to Telix, Doug held roles of Chief Financial Officer and Chief Operating Officer at ANSTO, Executive Chairman of ANSTO Nuclear Medicine, and Chief Financial Officer at DHL Oceania and South Pacific. "It’s been an incredible period of growth for Vaxxas and we are pleased to be strengthening our team with the appointment of Doug Cubbin as Chief Financial Officer,” Vaxxas Chief Executive Officer David Hoey said. “Doug’s extensive experience spans wide geographical regions, diverse market sectors, and complex regulatory environments, which brings tremendous value as we commercialize our vaccination technology platform.” Vaxxas Chief Financial Officer Doug Cubbin added, “The opportunity Vaxxas has to introduce a novel solution to traditional vaccination methods is incredibly exciting. I’m thrilled to be joining the business at this critical juncture and look forward to seeing the company continue to grow as we work towards bringing our first vaccination patch to market.” Doug’s appointment follows the recruitment to Vaxxas of Scott Fry as Chief Operating Officer and Daniel Devine as Chief Business Officer and General Counsel, earlier this year. Scott and Daniel joined Vaxxas from Ellume Limited and Mesoblast Limited, respectively. Vaxxas continues to experience significant growth and currently employs over 110 people. To support this growth, Vaxxas will move into a state-of-the-art manufacturing facility being built by the Queensland Government in Brisbane in early 2023. About Vaxxas’ HD-MAP technology The company’s proprietary HD-MAP technology platform utilizes an ultra-high-density array of projections – invisible to the naked human eye – applied to the skin as a patch sitting inside a small applicator device. When applied to the skin, the patch delivers vaccine to the abundant immune cells immediately below the skin surface. This approach has the potential to enhance the efficiency and effectiveness of resulting immune responses of vaccines. Vaxxas uses proprietary dry-coating technology to apply an active and stable vaccine onto the projections which offers the potential to eliminate the need for vaccine refrigeration during storage and transportation – reducing the resource and logistics burden of maintaining the refrigerated “cold chain”. Ease of use of the HD-MAP could enable simplified administration, potentially encompassing self-administration. Vaxxas' HD-MAP is coated with a vaccine candidate and integrated into a single-use applicator, ready-for-vaccination. All vaccine candidates applied to the Vaxxas HD-MAP are designed to be effective and easy-to-use, while meeting industrial-scale manufacturing and commercial logistics requirements. In extensive laboratory testing published in PLoS Med, Vaxxas’ HD-MAP delivered vaccines have shown to be stable and remain active when stored and transported at room temperature and demonstrate potential for a lower dose when compared to needle and syringe delivery of vaccine antigens. Vaxxas has completed three human clinical studies with its HD-MAP involving more than 300 participants, demonstrating enhanced immune response of vaccine administration by HD-MAP. About Vaxxas Vaxxas is a privately held biotechnology company focused on enhancing the performance of existing and next-generation vaccines with its proprietary high-density microarray patch (HD-MAP). Vaxxas is targeting initial applications in infectious disease and oncology. A Phase I clinical study of a COVID-19 vaccine candidate on a patch is currently underway. Vaxxas is also preparing for clinical evaluation under contract with the United States Biomedical Advanced Research and Development Authority (BARDA) on pandemic vaccination solutions. Vaxxas’ core technology was initially developed at The University of Queensland (UQ), and the company was established as a start-up in 2011 by UQ’s commercialization company UniQuest. The company was founded with the completion of an initial equity financing led by OneVentures Innovation Fund I with co-investors Brandon Capital Partners, Brandon BioCatalyst, and US-based HealthCare Ventures, followed by a further financing led by OneVentures. OneVentures Innovation Fund I and Brandon BioCatalyst are supported by the Australian Government’s Innovation Investment Fund (IIF) program. The IIF is an Australian Government venture capital initiative that provides investment capital and managerial expertise through licensed venture capital fund managers to investee companies. Learn more at and . Disclaimer Vaxxas’ HD-MAP delivered vaccines are under investigation and available only for investigational uses. They are not available anywhere in the world for sale or purchase. As such, Vaxxas makes no claim that the vaccines are reliable, durable, dependable, safe or effective, and makes no claim that it is superior to any other vaccine or vaccine delivery technology. View source version on businesswire.com: Contacts For media enquiries, please contact: In Australia: Amy Miller WE Communication +61 431 072 422 amymi@we-worldwide.com In United States: Kathryn Morris The Yates Network +1 914 204 6412 kathryn@theyatesnetwork.com Source: Vaxxas Smart Multimedia Gallery Photo Vaxxas CFO Doug Cubbin (Photo: Business Wire) Logo View this news release and multimedia online at: