Electrochemical CO 2 conversion into valuable products provides a promising solution for achieving a carbon-neutral energy cycle. Herein, an active and stable Bi/Nafion interface is fabricated over Bi nanosheets with the modification of Nafion, which exhibits superior CO 2 conversion with formate selectivity of above 95% in a wide potential range, partial current density of 72.12 mA cm −2 at − 1.07 V vs. RHE in H-type cell. The extraordinary CO 2 reduction performance could be ascribed to a high CO 2 permeability and enhanced local proton activity at the Bi/Nafion interface, which leads to promoted CO 2 adsorption and feasible proton-coupled electron transfer during the CO 2 reduction process. Computational investigations reveal the modification of Nafion offers a comfortable platform to enable the key intermediate *OCHO to be stable. This work offers a valuable insight into interfacial manipulation of electrodes to convert CO 2 to valuable products.
Graphene field-effect transistors (G-FETs) have attracted widespread attention in disease diagnosis, benefiting from these advantages of high sensitivity, label-free, easy integration, and direct detection of nucleic acids (NAs) in liquid environments. However, the problem of nonspecific signals in G-FETs is not fundamentally solved due to a lack of systematic theoretical research to support the development of effective solutions. Thus, researchers have to rely on speculative mechanisms to minimize nonspecific signals in experiments as much as possible. Herein, the nonspecific signal mechanism caused by eight types of π – π interaction paths mediated by aromatic rings is theoretically determined. Based on theoretical simulation results, the feasibility of blocking nonspecific signal paths through Nafion functionalization methods is experimentally verified. Experiments confirm that Nafion-modified G-FETs (NMG-FETs) have excellent performance in avoiding nonspecific signals compared to traditional G-FETs. Furthermore, the NMG-FET achieves ultra-sensitive detection of Down syndrome–related DNA down to 1 aM and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA down to 5 aM, and shows good specificity in base recognition. This study is expected to promote the theoretical advancement of the nonspecific signal mechanism in G-FET NA detection and offer a practical strategy for improving signal purity and accuracy.
危险品化学品经营许可证（带存储）