Recent advances of carbon dot-based memristors: Mechanisms, devices, and applications

Memristors are considered to hold promising applications in the fields of resistive random-access memory and synaptic bionic devices owing to their unique nonlinear electrical characteristics. Stability of performances is critical for memristors, in which functional layer materials are key. As novel functional layer materials, carbon dots (CDs) are zero-dimensional nanomaterials with a size of less than 10 nm. Owing to their distinctive features such as excellent thermal stability, high electrical conductivity, favorable dispersion and quantum effect, they can be used as functional layer materials for memristors either individually or in combination with other resistive materials to achieve satisfactory memristor regulation. This review summarizes the recent advances of CD-based memristors, including memristive mechanisms, devices, and applications. Firstly, the common memristive mechanisms of CD-based memristors are categorized as metal conductive filament mechanism, electron trapping and detrapping mechanism and oxygen vacancy conductive filament mechanism. Secondly, CDs-based memristors are classified into digital and analog types, and the effect of CDs on improving the performance of different types of memristors is further investigated. Finally, the current application fields of CD-based memristors at the present stage are reviewed, and the prospects for their development are prospected. This work is instructive for understanding the research progress of CD-based memristors and exploring the role of CDs in memristors, which brings the possibility of obtaining high-performance memristors for achieving better neuromorphic computing and data storage.