Novel approach improves graphene-based supercapacitors

EurekAlert  August 3, 2020 Researchers in Australia have developed a technique to improve the performance of quasi‐solid‐state supercapacitors made by graphitized silicon carbide on silicon electrodes and polyvinyl alcohol (PVA)+H2SO4 gel electrolyte. They increased the specific capacitance of the cell up to 3‐fold resulting from a simple agent‐free, in situ, electrochemical treatment leading to functionalization of the graphitic electrodes. The functionalization of the electrodes simultaneously enables redox reactions, without adding any redox agent, and increases the overall capacitance…read more. TECHNICAL ARTICLE

Supercapacitor promises storage, high power and fast charging

Science Daily  May 5, 2020 The overall electrochemical performance of the semiconductor heterostructures often depends on the carrier mobility from the semiconductor interfaces and faradaic redox reactions from their active sites. An international team of researchers (Pennsylvania State University, China) has developed low-cost, two-step method to controllably grow MnO2 nanorods directly on CoMn2O4 nanosheets with robust adhesion. An induced electric field resulted from the interface effect of heterostructures tailors the kinetic performance of electrons and ions during the charge-discharge process, enhancing the electron mobility and reducing diffusion barrier for charge carriers (OH−) ions migration. As a result, the rational design […]

Newly devised static negative capacitor could improve computing

Science Daily  April 8, 2019 Previously proposed designs for negative capacitors worked on a temporary, transient basis. An international team of researchers (France, Russia, USA Argonne National Laboratory) created a permanent static negative capacitor which works as a steady-state, reversible device. The prime component of the negative capacitor involves a filling made of a ferroelectric material. By splitting a nanoparticle into two equal ferroelectric domains of opposite polarization, separated by a boundary called a domain wall, they were able to minimize the effect of the total depolarizing electric field. They showed that the ferroelectric nanodot capacitor hosts a stable two-domain […]

3D-Printed Graphene Scaffold Breaks Capacitor Records

Inside Science  October 18, 2018 A team of researchers in the US (UC Santa Cruz, Lawrence Livermore National Laboratory) has made a 3D printed graphene aerogel electrode with MnO2 loading of 182.2 mg cm−2, which achieves a record-high areal capacitance of 44.13 F cm−2. the electrode can simultaneously achieve excellent capacitance normalized to area, gravimetry, and volume, which is the trade-off for most electrodes. The work successfully validates the feasibility of printing practical pseudocapacitive electrodes, which might revolutionize pseudocapacitor fabrication… read more. TECHNICAL ARTICLE