Sandwiched PbS/Au/PbS phototransistor for surface plasmon enhanced near-infrared photodetection

Vertically Stacked Au/PbS/CsPbCl3 Phototransistors for Plasmon-Enhanced High-Performance Broadband Photodetection

“…The EQEs of Au/PbS/CsPbCl 3 phototransistors are up to 135,129% (405 nm), 1,033,937% (532 nm), and 71,051% (808 nm), respectively. They are dramatically higher than the reported ITO/CsPbBr 3 /ITO photodetector (54%), Au/PbS photodetector (1251%), and MAPbI 3 :PbS QD photodetector (4500%), (Table ).…”

“…Inorganic cesium lead halide (CsPbX 3 , X = Cl, Br, and I) perovskites have been extensively used in photovoltaics, light-emitting diodes, and photodetection due to their good stability, tunable properties, novel functionalities, low cost, and facile synthesis. − In particular, cesium lead chloride nanoplatelets (CsPbCl 3 NPLs) are more attractive due to their excellent in-plane carrier transport, strong quantum confinement, and long carrier diffusion length. − For CsPbCl 3 NPLs, however, the intrinsically narrow absorption and poor photoresponse (mA/W) still hinder their large-scale application in optoelectronics. ,, To address these challenges, it is urgent to seek a desirable material with broadband optical absorption which can be combined with CsPbCl 3 NPLs to overcome the shortcomings. Previous reports have revealed that lead sulfide quantum dots (PbS QDs) are particularly suitable for this purpose due to broadband optical absorption, multiexciton effect, and high stability in ambient environment. − Photodetectors based on perovskites/PbS QDs have addressed the issues of narrow absorption (perovskites) as well as low carrier mobility (PbS QDs). , However, the small absorption cross section of PbS QDs is still a fundamental challenge. Fortunately, previous works have established a method to fabricate high-performance photodetectors by the combination of a photoactive layer with noble metal (Au or Ag) nanoparticles (NPs). − The coupling of the plasmonic near-field of metal NPs and photoactive layers increased the effective cross section of absorption; thus addressing the issues of poor photoresponse (perovskites) as well as small absorption cross sections (PbS QDs).…”

Six‐arm Stellat Dendritic‐PbS Flexible Infrared Photodetector for Intelligent Healthcare Monitoring

“…[13] However, photodetectors based on PbS nanosheets, PbS quantum dots, molybdenum disulfide, and other metal sulfides with different structures are unable to achieve wide-band detection. [19][20][21][22][23][24] Six-arm stellate dendritic (SASD) lead sulfide (SASD-PbS) with a direct band gap of 0.4 eV as a narrow band gap non-layered IVA metal sulfide effectively solves this problem. [20] The large size of SASD-PbS (2-3 μm) extends optical absorption to ultraviolet (365 nm) and the narrow band gap of 0.4 eV enables SASD-PbS to acquire the ability to absorb a wide spectrum (365-1550 nm) to guarantees that SASD-PbS can be responsive to "the window of biological spectroscopy".…”

“…[19][20][21][22][23][24] Six-arm stellate dendritic (SASD) lead sulfide (SASD-PbS) with a direct band gap of 0.4 eV as a narrow band gap non-layered IVA metal sulfide effectively solves this problem. [20] The large size of SASD-PbS (2-3 μm) extends optical absorption to ultraviolet (365 nm) and the narrow band gap of 0.4 eV enables SASD-PbS to acquire the ability to absorb a wide spectrum (365-1550 nm) to guarantees that SASD-PbS can be responsive to "the window of biological spectroscopy". At the same time, the unique SASD structure also greatly improves the optical absorption of SASD-PbS.…”

High-Responsivity Vis–NIR Photodetector Based on a Ag2S/CsPbBr3 Heterojunction

“…QDs have gained significant interest in optoelectronic devices such as photodetectors, solar cells, and energy storage devices . PbS QDs have great potential in the field of high-performance PDs due to their low-cost solution synthesis method, high quantum yield, high optical absorption coefficient, and high carrier mobility. − PbS QDs are used in IR PDs due to their tunable band-gap energies and excellent optical properties, but they usually contain toxic elements and are unable to cover the vis band. − Ag 2 S is a direct band-gap semiconductor (0.9–1.1 eV) with a vis–NIR spectral range. It has good chemical stability and optical properties.…”