Review: Hydrogen sensors based on polyaniline and its hybrid materials

As hydrogen gains momentum as a cornerstone of the global clean energy transition, ensuring its safe storage and transport is becoming increasingly critical. Researchers from Nazarbayev University in Kazakhstan have published a comprehensive mini-review in Discover Nano exploring how advanced materials based on polyaniline (PANI) and its hybrid nanocomposites could enable highly sensitive, low-power hydrogen sensors, a key technology for the safe expansion of hydrogen infrastructure.

The review, authored by Perizat Askar, Dana Kanzhigitova, Aslan Tapkharov, Kamshat Umbetova, Sagydat Duisenbekov, Salimgerey Adilov, and Nurxat Nuraje, synthesizes recent advances in nanostructured PANI materials, carbon-based composites, and metal oxide hybrids. The review examines sensing mechanisms, electrical behavior, and morphological design strategies that enhance hydrogen detection performance, while also addressing current limitations such as thermal stability and solubility.

Hydrogen can ignite at very low concentrations, making reliable leak detection essential for industrial safety and the future hydrogen economy. According to the researchers, conductive polymers like polyaniline offer unique advantages over conventional sensor materials, including room-temperature operation, flexibility, and low energy consumption.

"Polyaniline provides a versatile platform for designing next-generation hydrogen sensors because its electrical properties can be tuned through nanostructuring and hybridization," the authors note.

The review highlights how combining PANI with materials such as graphene, carbon nanotubes, metal oxides, and catalytic nanoparticles significantly improves sensitivity, response time, and selectivity. Hybrid systems can leverage synergistic effects—including enhanced charge transfer and increased surface area, to detect hydrogen more effectively under practical conditions.

"By integrating PANI with nanomaterials, we can overcome many of the limitations of conventional sensors and move closer to reliable, scalable monitoring technologies for hydrogen systems," the team explains.

Impacts

• Supporting the hydrogen economy: Advanced PANI-based sensors could improve safety across hydrogen production, storage, and transport infrastructure.
• Low-power monitoring: Room-temperature operation enables energy-efficient sensing solutions suitable for distributed monitoring networks.
• Materials innovation: The work provides a roadmap for designing hybrid nanomaterials with improved sensing performance.
• Global relevance: Safer hydrogen technologies are essential for achieving net-zero targets and accelerating clean energy deployment worldwide.

The review brings together findings from a wide range of studies to clarify how structural design including nanofibers, nanotubes, and heterostructures, influences sensing behavior. It also outlines future research priorities, such as improving long-term stability, selectivity, and large-scale manufacturability.

By mapping current progress and identifying key challenges, the authors aim to support the development of robust hydrogen sensing technologies that can operate reliably in real-world environments.

More information:
Perizat Askar et al, Hydrogen sensors based on polyaniline and its hybrid materials: a mini review, Discover Nano (2025). DOI: 10.1186/s11671-025-04231-9

Provided by Nazarbayev University