Broadband NIR photoelectronic performance for sunlight‐induced photocurrent from (NaYF₄:Yb‐Er)/BiOI hybrid films

Abstract

The fabrication and near‐infrared optoelectronic performance of the (NaYF4:Yb‐Er)/BiOI upconversion phosphor/semiconductor hybrid films are reported. The composite films were fabricated by a simple electro‐deposition and successive ionic layer adsorption and reaction (SILAR) method. We observed efficient upconversion emissions in the film of NaYF4:Yb‐Er upon irradiation by near‐infrared part of simulated sunlight, and the UC emission is drastically quenched in the composite film (NaYF4:Yb‐Er)/BiOI. More importantly, this composite film displays unusual negative photoresponse to near‐infrared part of simulated sunlight when used in a standard electrochemical cell where the composite film serves as the photoanode. This result may pave the way for potential application of this hybrid films for the development of novel photovoltaic and infrared optoelectronic devices.

One‐pot combustion synthesis and efficient broad spectrum photoactivity of Bi/BiOBr:Yb,Er/C photocatalyst

“…Figure C shows the up‐conversion spectrum of PL spectrum of BiOBr:Yb,Er and Bi/BiOBr:Yb,Er/C under 980 nm excitation. For BiOBr:Yb,Er, characteristic peaks at 660, 545, and 525 nm are observed and can be assigned to 4 F 9/2 → 4 I 15/2 , 4 S 3/2 → 4 I 15/2 , and 2 H 11/2 → 4 I 15/2 transitions of Er 3+ , respectively, indicating the successful up‐conversion of 980 nm to visible light. However, the 545 and 525 nm emissions in Bi/BiOBr:Yb,Er/C are significantly suppressed.…”

Nanostructures/Graphene/Silicon Junction‐Based High‐Performance Photodetection Systems: Progress, Challenges, and Future Trends

“…Many researchers investigated the effects of doping and film thickness on the photoresponse and photodetection of various materials in the UV to NIR domains. [ 130–136 ] Fang et al. reported the effect of layering dynamics on the optical response of graphene.…”

“…[129] Many researchers investigated the effects of doping and film thickness on the photoresponse and photodetection of various materials in the UV to NIR domains. [130][131][132][133][134][135][136] Fang et al reported the effect of layering dynamics on the optical response of graphene. [137] The constant movement of the zero-cross point in the intricate optical conductivity's imaginary component, which is made possible by an increase in thickness, is what gives graphene its adjustable optical responsiveness.…”