Enhanced Photocurrent in BiFeO₃ Materials by Coupling Temperature and Thermo-Phototronic Effects for Self-Powered Ultraviolet Photodetector System

Abstract

Ferroelectric materials can be utilized for fabricating photodetectors because of the photovoltaic effect. Enhancing the photovoltaic performance of ferroelectric materials is still a challenge. Here, a self-powered ultraviolet (UV) photodetector is designed based on the ferroelectric BiFeO (BFO) material, exhibiting a high current/voltage response to 365 nm light in heating/cooling states. The photovoltaic performance of the BFO-based device can be well modulated by applying different temperature variations, where the output current and voltage can be enhanced by 60 and 75% in heating and cooling states, respectively. The enhancement mechanism of the photocurrent is associated with both temperature effect and thermo-phototronic effect in the photovoltaic process. Moreover, a 4 × 4 matrix photodetector array has been designed for detecting the 365 nm light distribution in the cooling state by utilizing photovoltage signals. This study clarifies the role of the temperature effect and the thermo-phototronic effect in the photovoltaic process of the BFO material and provides a feasible route for pushing forward practical applications of self-powered UV photodetectors.

Multiferroics beyond electric-field control of magnetism

“…(Bi,Sr)FeO 3 , with its high concentration of oxygen vacancies combined with high vacancy mobility, likely due to its large polarizability, shows promise for solid-oxide fuel cells [50]. A high Seebeck coefficient has been reported, suggesting possible thermoelectric relevance [51], as well as photostriction [52], photodetection [53], and gas sensing behavior [54,55]. Finally, resistive switching, with possible application in neuromorphic computing, has been reported [56].…”

Photovoltaic–Pyroelectric–Piezoelectric Coupled Effect Induced Electricity for Self‐Powered Coupled Sensing

“…Considering the complexity and variety of the energies in ambient environment, we further investigated the sensing performance of the device under light+heating+vibration coupled conditions. In the experimental protocol, the heating condition is maintained at a temperature difference ΔT of 12.9 K, and the light intensity (20-211 mW cm −2 ) and vibration frequency (11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26) are served as experimental variables. The measured real-time output current signals I Photo+Pyro+Piezo under different light+heating+vibration coupling conditions are recorded in detail, as illustrated in Figure 5 and Figures S18 and S19 (Supporting Information).…”

“…[16][17][18] As so far, a variety of self-powered sensors based on ferroelectric materials have been successfully fabricated and characterized by using LiNbO 3 , Pb(Zr,Ti)O 3 , BiFeO 3 , and BaTiO 3 (BTO), as sensitive materials. [19][20][21][22] Especially, the BTO materials have been widely utilized for light and pressure sensing applications due to their outstanding characteristics of innocuity, stability, and high piezoelecric constant. [23,24] Due to the coexistence of photo voltaic, pyroelectric, and piezoelectric effects, it is allowed for the ferroelectric materials to sense light, temperature, and pressure simultaneously.…”

Structure Design and Performance of Hybridized Nanogenerators

“…Over the years, researchers have made great progress in enhancing the charge transfer to improve the performance of solar cells from both aspects of material design and configuration optimization . Meanwhile, the rapid development of nanogenerators promotes the regulation of internal electric field of solar cells by ambient strain or temperature excitation, mainly through piezoelectric potential, pyroelectric potential, and thermoelectric potential . In 2016, Zhang et al first demonstrated the largely enhanced performance of poly(3‐hexylthiophene) (P3HT)/ZnO solar cell using the pyro‐phototronic effect when the device is subjected to a temperature fluctuation under weak light illuminations, as shown in Figure a.…”