Emerging materials for resistive switching memories: Prospects for enhanced sustainability and performance for targeted applications

Resistive switching (RS) memories are novel devices that have attracted significant attention recently in view of their potential integration in deep neural networks for intense big data processing within the explosive artificial intelligence era. While oxide- or silicon-based memristive devices have been thoroughly studied and analyzed, there are alternative material technologies compatible with lower manufacturing cost and less environmental impact exhibiting RS characteristics, thus providing a versatile platform for specific in-memory computing and neuromorphic applications where sustainability is a priority. The manufacturing of these emerging RS technologies is based on solution-processed methods at low temperatures onto flexible substrates, and in some cases, the RS active layer is composed of natural, environmentally friendly materials replacing expensive deposition methods and critical raw and toxic materials. In this Perspective, we provide an overview of recent developments in the field of solution-processed and sustainable RS devices by providing insights into their fundamental properties and switching mechanisms, categorizing key figures of merit while showcasing representative use cases of applications of each material technology. The challenges and limitations of these materials for practical applications are analyzed along with suggestions to resolve these pending issues.