No abstract

Current rapid development of big data, Internet of Things, and artificial intelligence require exponentially higher data storage capacity. The memristor technology, which stores data by controlling resistance states, demonstrates great prospects in resistive random-access memory (RRAM), synapse construction, and neuromorphic computing. However, traditional memristor devices can only store 1-bit of data by tuning two separate resistance states, which limits their storage density. Herein, a water-coupled Ag/TiO 2 _few-layer graphene_TiO 2 /Al memristor is developed as a multibit data storage system. The high and low resistance state ratio (HRS/LRS) increases from 5 to 44 when water is coupled in the device. An electrocatalytic hydrolysis-modulated resistive switching mechanism is proposed for the physical phenomenon. Herein, not only a multilevel per cell (MLC) storage device is developed, but also a novel electrocatalysis coupling mechanism for memristor technology is provided.

Advancement of a hydrogen economy requires establishment of a whole supply chain including hydrogen production, purification, storage, utilization, and recovery. Nevertheless, it remains challenging to selectively purify hydrogen out of H 2 -containing streams, especially at low concentrations. Herein, a novel protonic ceramic electrochemical cell is reported that can sustainably separate pure H 2 out of H 2 -diluted streams over the temperature regime of 350−500 °C by mildly controlling the electric voltage. With the Faraday's efficiency above 96%, the measured H 2 separation rate at 0.51 V and 500 °C is 3.3 mL cm −2 min −1 out of 10% H 2 -90% N 2 , or 2.4 mL cm −2 min −1 out of 10% H 2 -90% CH 4 taken as an example of renewable hydrogen blended in the natural gas pipelines. Such high hydrogen separation capability at reduced temperatures is enabled by the nanoporous nickel catalysts and well-bonded electrochemical interfaces as produced from well-controlled in situ slow reduction of nickel oxides. These results demonstrate technical feasibility of onsite purification of hydrogen prior to their practical applications such as fuels for fuel cell electric vehicles.