Integrated near-field thermophotovoltaic device overcoming far-field blackbody limit

TL;DR

This paper demonstrates a novel integrated near-field thermophotovoltaic device that surpasses the far-field blackbody limit, achieving significantly higher power output and efficiency, with promising implications for practical TPV applications.

Contribution

The paper presents the first experimental demonstration of a one-chip near-field TPV device surpassing the far-field blackbody limit with integrated components and detailed performance analysis.

Findings

Photocurrent density of 1.49 A/cm2 at 1192 K, 1.5 times the far-field limit.

Output power of 1.92 mW and efficiency of 0.7% for a 1-mm2 device.

Potential for >35% system efficiency in scaled-up devices.

Abstract

Near-field thermal radiation transfer overcoming the far-field blackbody limit has attracted significant attention in recent years owing to its potential for drastically increasing the output power and conversion efficiency of thermophotovoltaic (TPV) power generation systems. Here, we experimentally demonstrate a one-chip near-field TPV device overcoming the far-field blackbody limit, which integrates a 20-um-thick Si emitter and an InGaAs PV cell with a sub-wavelength gap (<140 nm). The device exhibits a photocurrent density of 1.49 A/cm2 at 1192 K, which is 1.5 times larger than the far-field limit at the same temperature. In addition, we obtain an output power of 1.92 mW and a system efficiency of 0.7% for a 1-mm2 device, both of which are one to two orders of magnitude greater than those of the previously reported near-field systems. Detailed comparisons between the simulations and experiments reveal the possibility of a system efficiency of >35% in the up-scaled device, thus demonstrating the potential of our integrated near-field TPV device for practical use in the future.