English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Over the past years, thermionic energy conversion (TEC) with a reducedinter-electrode vacuum gap has been studied as an effective way to mitigate alarge potential barrier due to space charge accumulation. However, existingtheoretical models do not fully consider the fundamental aspects of thermionicemission when the inter-electrode gap shrinks to the nanoscale, which resultsin underestimation of thermionic power generation for such small gaps. Thepresent work addresses this challenge by comprehensively modeling charge andthermal transport processes with specific consideration of nanoscale gapeffects, such as image charge perturbation, electron tunneling, and near-fieldthermal radiation. Carefully conducted energy balance analysis reveals that ifoptimized, submicron-gap TEC can excel the micron-gap counterpart with $\sim$4times the power output and ~5-10 % higher energy conversion efficiency.Moreover, the high-temperature collector of the submicron-gap TEC, which is dueto thermionic and near-field radiative heat transfer, allows the addition of abottom-cycle heat engine to further enhance the power and efficiency whencombined. Electric field concentration due to engineered surface roughness isalso examined as a potential approach to produce an additional increase inpower generation. We believe that the present work provides a theoreticalframework for submicron-gap thermionic power generation as a promising energyrecycling scheme for high-quality heat sources.

Revisiting Submicron-Gap Thermionic Power Generation Based on Comprehensive Charge and Thermal Transport Modeling