Work

Experimental characteristics of thermionic energy converters employing barium-dispenser cathode and semiconductor anodes

Year: 2025

Type: article

Abstract: Thermionic energy converter (TEC) is a promising direct energy conversion technology which is expected to attain high efficiency approaching the ideal Carnot cycle . The exploration for low work function electrode materials and the alleviation of space charge effect have long been significant topics. In this work, TEC prototypes with Mo, n-type GaAs (nGaAs) and graphene/n-type GaAs Schottky heterojunction (Gr/nGaAs) anodes were developed and measured, respectively. The influences of cathode temperature, work function and space charge effect were analyzed by varying the cathode temperature and electrode gap . The electronic barrier was calculated to evaluate the space charge effect and exhibits an upward tendency with the increase of temperature and electrode gap . The experimental results indicate that the TEC with nGaAs anode exhibits the best performance. Notably, the output power of TEC with nGaAs anode shows an enhancement of 8.5-fold and 1.8-fold compared to that of Mo anode and Gr/nGaAs anode at 1398 K, respectively. In addition, the open-circuit voltage of nGaAs anode TEC was 0.57 V higher than that of the Gr/nGaAs anode TEC at 1398 K. This work not only provides a reference for the selection of TEC anode materials , but also paves the way for future researches aimed at achieving high output power in TECs.

Source: Energy

DOI: 10.1016/j.energy.2025.136132

Authors: Mengyuan Hao, Gang Xiao, Hao Qiu

Institutions: Shandong University, State Key Laboratory of Clean Energy Utilization, Zhejiang University

Language: English

Topic: Advanced Thermoelectric Materials and Devices

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: hybrid

Estimated APC paid: $4,260