Surface plasmon mediates the visible light-responsive lithium-oxygen battery with Au nanoparticles on defective carbon nitride.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 33879619.
- Also identified by DOI 10.1073/pnas.2024619118 and PMC identifier 8092409.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Aprotic lithium-oxygen (Li-O<sub>2</sub>) batteries have gained extensive interest in the past decade, but are plagued by slow reaction kinetics and induced large-voltage hysteresis. Herein, we use a plasmonic heterojunction of Au nanoparticle (NP)-decorated C<sub>3</sub>N<sub>4</sub> with nitrogen vacancies (Au/N<sub>V</sub>-C<sub>3</sub>N<sub>4</sub>) as a bifunctional catalyst to promote oxygen cathode reactions of the visible light-responsive Li-O<sub>2</sub> battery. The nitrogen vacancies on N<sub>V</sub>-C<sub>3</sub>N<sub>4</sub> can adsorb and activate O<sub>2</sub> molecules, which are subsequently converted to Li<sub>2</sub>O<sub>2</sub> as the discharge product by photogenerated hot electrons from plasmonic Au NPs. While charging, the holes on Au NPs drive the reverse decomposition of Li<sub>2</sub>O<sub>2</sub> with a reduced applied voltage. The discharge voltage of the Li-O<sub>2</sub> battery with Au/N<sub>V</sub>-C<sub>3</sub>N<sub>4</sub> is significantly raised to 3.16 V under illumination, exceeding its equilibrium voltage, and the decreased charge voltage of 3.26 V has good rate capability and cycle stability. This is ascribed to the plasmonic hot electrons on Au NPs pumped from the conduction bands of N<sub>V</sub>-C<sub>3</sub>N<sub>4</sub> and the prolonged carrier life span of Au/N<sub>V</sub>-C<sub>3</sub>N<sub>4</sub> This work highlights the vital role of plasmonic enhancement and sheds light on the design of semiconductors for visible light-mediated Li-O<sub>2</sub> batteries and beyond.