NIR QDs

Ag2 S quantum dots (QDs) show superior optical properties in the NIR-II region and display significant clinical potential with favorable biocompatibility. However, inherent defects of low targeting and poor solubility necessitate practical modification methods to achieve the theranostics of Ag2 S QDs. Herein, we used rolling circle amplification (RCA) techniques to obtain long single-stranded DNA containing the PD-L1 aptamer and C-rich DNA palindromic sequence. The C-rich DNA palindromic sequences can specifically chelate Ag2+ and thus serve as a template to result in biomimetic mineralization and formation of pApt-Ag2 S QDs...

CuInS2 (CIS) quantum dots (QDs) represent an important class of colloidal materials with broad application potential, owing to their low toxicity and unique optical properties. Although coating with a ZnS shell has been identified as a crucial method to enhance optical performance, the occurrence of cation exchange has historically resulted in the unintended formation of Cu-In-Zn-S alloyed QDs, causing detrimental blueshifts in both absorption and photoluminescence (PL) spectral profiles. In this study, we present a facile one-pot synthetic strategy aimed at impeding the cation exchange process and promoting ZnS shell growth on CIS core QDs...

Broadband photodetectors have drawn intensive attention owing to their wide application prospects in optical communication, imaging, astronomy, and so on. Two-dimensional transition-metal dichalcogenides (TMDs) are considered as highly potential candidates for photodetection applications, benefiting from their excellent photoelectric properties. However, most of the photodetectors based on TMDs suffer from low performance in the near-infrared (NIR) region due to the weak optical absorption efficiency near their absorption band edge, which severely constrains their usage for broadband optoelectronics...

Colloidal quantum dots/graphene (QD/Gr) nanohybrids have been studied intensively for photodetection in a broadband spectrum including ultraviolet, visible, near-infrared, and shortwave infrared (UV-vis-NIR-SWIR). Since the optoelectronic process in the QD/Gr nanohybrid relies on the photogenerated charge carrier transfer from QDs to graphene, understanding the role of the QD-QD and QD-Gr interfaces is imperative to the QD/Gr nanohybrid photodetection. Herein, a systematic study is carried out to probe the effect of these interfaces on the noise, photoresponse, and specific detectivity in the UV-vis-NIR-SWIR spectrum...

The remarkable properties of two-dimensional (2D) materials have led to significant advancements in photodetection and optoelectronics research. Currently, there are many successful methods that are employed to improve the responsivity of photodetectors, but the limited spectral range of the device remains a limitation. This work demonstrates the development of a mixed-dimensional (2D/0D) hybrid photodetector device fabricated using chemical vapor deposition (CVD)-grown monolayer ReS2 and solution-processed MoS2 quantum dots (QDs)...

The anti-Stokes shift represents the capacity of photon upconversion to convert low-energy photons to high-energy photons. Although triplet exciton-mediated photon upconversion presents outstanding performance in solar energy harvesting, photoredox catalysis, stereoscopic 3D printing, and disease therapeutics, the interfacial multistep triplet exciton transfer leads to exciton energy loss to suppress the anti-Stokes shift. Here, we report near infrared-II (NIR-II) excitable triplet exciton-mediated photon upconversion using a hybrid photosensitizer consisting of lead sulfide quantum dots (PbS QDs) and new surface ligands of thiophene-substituted diketopyrrolopyrrole (Th-DPP)...

Developing the second near-infrared (NIR-II) photoacoustic (PA) agent is of great interest in bioimaging. Ag2 Se quantum dots (QDs) are one kind of potential probe for applications in NIR-II photoacoustic imaging (PAI). However, the surfaces with excess anions of Ag2 Se QDs, which increase the probability of nonradiative transitions of excitons benefiting PA imaging, are not conducive to binding electron donor ligands for potential biolabeling and imaging. In this study, Staphylococcus aureus (S. aureus) cells are driven for the biosynthesis of Ag2 Se QDs with catalase (CAT)...

The development of indium phosphide (InP)-based quantum dots (QDs) with a near-infrared (NIR) emission area still lags behind the visible wavelength region and remains problematic. This study describes a one-step in situ pseudohalogen ammonium salt-assisted approach to generate NIR-emitted InP-based QDs with high photoluminescence quantum yields (PLQYs). The coexistence of NH4 + and PF6 - ions from NH4 PF6 may in situ synchronously etch and passivate the surface oxides and impede the creation of traps under the whole growth process of InP QDs...

Blends comprising organic semiconductors and inorganic quantum dots (QDs) are relevant for many optoelectronic applications and devices. However, the individual components in organic-QD blends have a strong tendency to aggregate and phase-separate during film processing, compromising both their structural and electronic properties. Here, we demonstrate a QD surface engineering approach using electronically active, highly soluble semiconductor ligands that are matched to the organic semiconductor host material to achieve well-dispersed inorganic-organic blend films, as characterized by X-ray and neutron scattering, and electron microscopies...

Early detection of renal fibrosis (RF) is very important given that it is irreversible when it progresses to the terminal stage. A key marker of RF pathogenesis is activation of myomyofibroblasts, and its targeted imaging may be a promising approach for early detection of RF, but there is no study has directly imaged activation of renal myomyofibroblasts. Cu2+ plays a major role in the fibrotic activity of myofibroblasts. Herein, inspired by that Cu2+ can complex with bovine serum albumin (BSA), BSA-Ag2 S QDs with aggregation-induced emission (AIE) property were synthesized...

Conventional luminescent solar concentrators (LSCs) usually only have the ability to absorb solar energy and convert it to electricity but are not able to regulate the transmitted light. Herein, a multistate thermoresponsive smart window (SW) based on LSC has been fabricated, in which the stimuli-responsive host layer consists of polydimethylsiloxane (PDMS) and ethylene glycol solution (EGS) microdroplets stacking with LSC layer-based on near-infrared (NIR) CuInSe2- x S x /ZnS core/shell quantum dots (QDs) and PDMS matrix...

Semiconductor quantum dots (QD) are a kind of nanoparticle with unique optical properties that have attracted a lot of attention in recent years. In this paper, the characteristics of these nanoparticles and their applications in nanophototherapy have been reviewed. Phototherapy, including photodynamic therapy (PDT) and photothermal therapy (PTT), has gained special importance because of its high accuracy and local treatment due to the activation of the drug at the tumor site. PDT is a new way of cancer treatment that is performed by activating light-sensitive compounds named photosensitizers (PS) by light...

Photon upconversion is a process that combines low-energy photons to form useful high-energy photons. There are potential applications in photovoltaics, photocatalysis, biological imaging, etc. Semiconductor quantum dots (QDs) are promising for the absorption of these low-energy photons due to the high extinction coefficient of QDs, especially in the near infrared (NIR). This allows the intriguing use of diffuse light sources such as solar irradiation. In this review, we describe the development of this organic-QD upconversion platform based on triplet-triplet annihilation, focusing on the dark exciton in QDs with triplet character...

While multiplexed fluorescence imaging is frequently used for in vitro microscopy, extending the technique to whole animal imaging in vivo has remained challenging due to the attenuation and scattering of visible and traditional near infrared (NIR-I) wavelengths. Fluorescence imaging using short-wave infrared (SWIR, 1000 - 1700 nm, a.k.a. NIR-II) light enables deeper tissue penetration for preclinical imaging compared to previous methods due to reduced tissue scattering and minimal background autofluorescence in this optical window...

Intracellular singlet oxygen (1 O2 ) generation and detection help optimize the outcome of photodynamic therapy (PDT). Theranostics programmed for on-demand phototriggered 1 O2 release and bioimaging have great potential to transform PDT. We demonstrate an ultrasensitive fluorescence turn-on sensor-sensitizer-RGD peptide-silica nanoarchitecture and its 1 O2 generation-releasing-storing-sensing properties at the single-particle level or in living cells. The sensor and sensitizer in the nanoarchitecture are an aminomethyl anthracene (AMA)-coumarin dyad and a porphyrin or CdSe/ZnS quantum dots (QDs), respectively...

The development of photocatalysts that effectively utilize low-energy photons for efficient photocatalysis still faces a number of challenges. Herein, an efficient NIR-driven system based on WO3-x /ZnIn2 S4 (WO3-x /ZIS) prepared by a simple low-temperature water-bath method, and the optimal WO3-x /ZIS-3 composites can reach a hydrogen-production efficiency of 14.05 μmol g-1 h-1 under NIR light irradiation. The localized surface plasmon (LSPR) resonance effect in WO3-x quantum dots (QDs) not only broadens the ZIS photo-response range, but also the photothermal effect of WO3-x can increase the local reaction temperature of WO3-x /ZIS composite system, thus enhancing the photothermal-assisted photocatalytic activity...

Partial epithelial-mesenchymal transition (pEMT) plays a vital role in oral squamous cell carcinoma (OSCC) cervical lymph node metastasis and tumor immune escape as an immune barrier. However, targeted interventions for pEMT have yet to be established. In this study, we generated an αPDPN-Ag2 S probe by modifying a Podoplanin(PDPN) monoclonal antibody on the surface of near infrared (NIR)-II Ag2 S quantum dots (QDs) with carboxyl groups through an amide reaction. Then, we evaluated its in vivo targeting ability, therapeutic efficacy of eliminating pEMT using αPDPN-Ag2 S-mediated NIR-II photoimmunotherapy (PIT) and biological safety...

The photothermal performance of black phosphorus (BP) in the near infrared (NIR)-II bio-window (1000-1500 nm) is low, which limits its biomedical applications. Herein, ultrasmall nickel phosphide quantum dots (Ni2 P QDs) are synthesized with BP quantum dots (BPQDs) as the template by topochemical transformation. The size of Ni2 P QDs is ≈3.5 nm, similar to that of BPQDs, whereas the absorption and photothermal conversion efficiency of Ni2 P QDs at 1064 nm (43.5%) are significantly improved compared with those of BPQDs...

The demand for self-powered photodetectors (PDs) capable of NIR detection without external power is growing with the advancement of NIR technologies such as LIDAR and object recognition. Lead sulfide quantum dot-based photodetectors (PbS QPDs) excel in NIR detection; however, their self-powered operation is hindered by carrier traps induced by surface defects and unfavorable band alignment in the zinc oxide nanoparticle (ZnO NP) electron-transport layer (ETL). In this study, an effective azide-ion (N3 - ) treatment is introduced on a ZnO NP ETL to reduce the number of traps and improve the band alignment in a PbS QPD...

Elongated nanoparticles show distinct advantages over spherical nanoparticles in bioimaging because of surface area-to-volume, rate of clearance from the body and elimination mechanism. In this work, we investigated the fluorescence emission properties of the hybrid system by decorating silver sulfide quantum dots (Ag2 S QDs) in situ on the surface of cellulose nanocrystal (CNC) with unique rod shape, modifiability and biocompatibility. This water-dispersible fluorescent probe has both absorption and fluorescence in near-infrared (NIR) region...