A molecular pyroelectric enabling broadband photo-pyroelectric effect towards self-driven wide spectral photodetection

Abstract

Broadband spectral photoresponse has shown bright prospects for various optoelectronic devices, while fulfilling high photoactivity beyond the material bandgap is a great challenge. Here, we present a molecular pyroelectric, N-isopropylbenzylaminium trifluoroacetate ( N-IBATFA), of which the broadband photo-pyroelectric effects allow for self-driven wide spectral photodetection. As a simple organic binary salt, N-IBATFA possesses a large polarization (~9.5 μC cm ⁻²), high pyroelectric coefficient (~6.9 μC cm ⁻² K ⁻¹) and figures-of-merits ( F _V = 187.9 × 10 ⁻² cm ² μC ⁻¹; F _D = 881.5 × 10 ⁻⁵Pa ^−0.5) comparable to the state-of-art pyroelectric materials. Particularly, such intriguing attributes endow broadband photo-pyroelectric effect, namely, transient currents covering ultraviolet (UV, 266 nm) to near-infrared (NIR, 1950 nm) spectral regime, which breaks the restriction of its optical absorption and thus allows wide UV-NIR spectral photodetection. Our finding highlights the potential of molecular system as high-performance candidates toward self-powered wide spectral photodetection.

Abstract

Broadband spectral photoresponse has potential for optoelectronic devices, but obtaining high photoactivity beyond the material bandgap is challenging. Here, the authors report the development of a molecular pyroelectric material with broadband photopyroelectric effects.