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As a result of an ongoing global dedication, metal‐halide perovskite (PVSK) has proven to be a promising substitute among other developed materials for next‐generation photovoltaic cells due to significantly high efficiency, economical reasons, environmentally friendly processing, and bandgap alterations. In just 12 years, PVSK‐based single cells have achieved an efficiency of 26.1%, reaching single‐crystal silicon solar cells at 27.6% and silicon heterostructure solar cells at 26.8%. PVSK‐based tandem cells also have achieved remarkable attention as a viable candidate for future‐generation photovoltaic technology. Currently, a considerable number of reports are documented as evidence of the efforts to integrate the wide‐bandgap PVSK either with itself (narrow‐bandgap PVSK ([NBG‐PVSK]) or other traditional (NBG) cells, including silicon (Si), copper–indium–gallium–selenide, organic solar cells, cadmium telluride (CdTe), and dye‐sensitized. Thanks to the substantial growth made in the advances of PVSK‐based tandem cells both in the laboratories and in the commercialization sector, this review will systematically elucidate the emergence of PVSK‐based cells, their current status, and applications in tandem configurations. Furthermore, this survey will cover the analysis of different strategies and efforts to achieve cutting‐edge photovoltaic technology. Finally, the commercialization of different PVSK‐based tandem technologies and their prospects are analyzed. [ABSTRACT FROM AUTHOR]

As a result of full‐scale ongoing global efforts, the power conversion efficiency (PCE) of the organic‐inorganic metal halide perovskite has skyrocketed. Unfortunately, the long‐term operational stability for commercialization standards is still lagging owing to intrinsic defects such as ion migration‐induced degradation, undercoordinated Pb2+, and shallow defects initiated by disordered crystal growth. Herein, we employed multifunctional, non‐volatile tetra‐methyl guanidine hydrochloride [TMGHCL] ionic liquid (IL) as an additive to elucidate defects' passivation effects on organic‐inorganic metal halide perovskite. More specifically, the formation of hydrogen bonds between H+ in GA+ and I− and coordinate bonding between Cl− and undercoordinated Pb2+ could significantly passivate these defects. The hypothesis was confirmed by both experimental and DFT simulations displaying that the optimized ratio of IL integration restrains ion migration, improving grains' size, and significantly elongating the carrier lifetime. Remarkably, the modified cell achieved a peak efficiency of 22.00 % with negligible hysteresis, compared to the control device's PCE of 20.12 %. In addition, the TMGHCL‐based device retains its 93.29 % efficiency after 16 days of continuous exposure to air with a relative humidity of 35±5% and temperature of 25±5 °C. This efficient approach of adding IL to perovskites absorber can produce high PCE and has strong commercialization potential. [ABSTRACT FROM AUTHOR]

Afterglow imaging holds great promise for ultrasensitive bioimaging due to its elimination of autofluorescence. Self‐sustaining afterglow molecules (SAMs), which enable all‐in‐one photon sensitization, chemical defect formation and afterglow generation, possess a simplified, reproducible, and efficient superiority over commonly used multi‐component systems. However, there is a lack of SAMs, particularly those with much brighter near‐infrared (NIR) emission and structural flexibility for building high‐contrast activatable imaging probes. To address these issues, this study for the first time reports a methylene blue derivative‐based self‐sustaining afterglow agent (SAN‐M) with brighter NIR afterglow chemiluminescence peaking at 710 nm. By leveraging the structural flexibility and tunability, an activatable nanoprobe (SAN‐MO) is customized for simultaneously activatable fluoro‐photoacoustic and afterglow imaging of peroxynitrite (ONOO−), notably with a superior activation ratio of 4523 in the afterglow mode, which is at least an order of magnitude higher than other reported activatable afterglow systems. By virtue of the elimination of autofluorescence and ultrahigh activation contrast, SAN‐MO enables early monitoring of the LPS‐induced acute inflammatory response within 30 min upon LPS stimulation and precise image‐guided resection of tiny metastatic tumors, which is unattainable for fluorescence imaging. [ABSTRACT FROM AUTHOR]

The pursuit of highly efficient and stable wide‐band gap (WBG) perovskite solar cells (PSCs), especially for monolithic perovskite/silicon tandem devices, is a key focus in achieving the commercialization of perovskite photovoltaics. In this study, we initially designed poly(ionic liquid)s (PILs) with varying alkyl chain lengths based on density functional theory calculations. Results pinpoint that PILs with longer alkyl chain lengths tend to exhibit more robust binding energy with the perovskite structure. Then we synthesized the PILs to craft a hydrophobic hydrogen‐bonded polymer network (HHPN) that passivates the WBG perovskite/electron transport layer interface, inhibits ion migration and serves as a barrier layer against water and oxygen ingression. Accordingly, the HHPN effectively curbs nonradiative recombination losses while facilitating efficient carrier transport, resulting in substantially enhanced open‐circuit voltage (Voc) and fill factor. As a result, the optimized single‐junction WBG PSC achieves an impressive efficiency of 23.18 %, with Voc as high as 1.25 V, which is the highest reported for WBG (over 1.67 eV) PSCs. These devices also demonstrate outstanding thermostability and humidity resistance. Notably, this versatile strategy can be extended to textured perovskite/silicon tandem cells, reaching a remarkable efficiency of 28.24 % while maintaining exceptional operational stability. [ABSTRACT FROM AUTHOR]

Afterglow luminescence imaging probes, with long‐lived emission after cessation of light excitation, have drawn increasing attention in biomedical imaging field owing to their elimination of autofluorescence. However, current afterglow agents always suffer from an unsatisfactory signal intensity and complex systems consisting of multiple ingredients. To address these issues, this study reports a near‐infrared (NIR) afterglow luminophore (TPP‐DO) by chemical conjugation of an afterglow substrate and a photosensitizer acting as both an afterglow initiator and an energy relay unit into a single molecule, resulting in an intramolecular energy transfer process to improve the afterglow brightness. The constructed TPP‐DO NPs emit a strong NIR afterglow luminescence with a signal intensity of up to 108 p/s/cm2/sr at a low concentration of 10 μM and a low irradiation power density of 0.05 W/cm2, which is almost two orders of magnitude higher than most existing organic afterglow probes. The highly bright NIR afterglow luminescence with minimized background from TPP‐DO NPs allows a deep tissue penetration depth ability. Moreover, we develop a GSH‐activatable afterglow probe (Q‐TPP‐DO NPs) for ultrasensitive detection of subcutaneous tumor with the smallest tumor volume of 0.048 mm3, demonstrating the high potential for early diagnosis and imaging‐guided surgical resection of tumors. [ABSTRACT FROM AUTHOR]

The photoelectric properties of nontoxic Sn‐based perovskite make it a promising alternative to toxic Pb‐based perovskite. It has superior photovoltaic performance in comparison to other Pb‐free counterparts. The facile oxidation of Sn2+ to Sn4+ presents a notable obstacle in the advancement of perovskite solar cells that utilize Sn, as it adversely affects their stability and performance. The study revealed the presence of a Sn4+ concentration on both the upper and lower surfaces of the perovskite layer. This discovery led to the adoption of a bi‐interface optimization approach. A thin layer of Sn metal was inserted at the two surfaces of the perovskite layer. The implementation of this intervention yielded a significant decrease in the levels of Sn4+ and trap densities. The power conversion efficiency of the device was achieved at 14.31 % through the optimization of carrier transportation. The device exhibited operational and long‐term stability. [ABSTRACT FROM AUTHOR]

The photoelectric properties of nontoxic Sn‐based perovskite make it a promising alternative to toxic Pb‐based perovskite. It has superior photovoltaic performance in comparison to other Pb‐free counterparts. The facile oxidation of Sn2+ to Sn4+ presents a notable obstacle in the advancement of perovskite solar cells that utilize Sn, as it adversely affects their stability and performance. The study revealed the presence of a Sn4+ concentration on both the upper and lower surfaces of the perovskite layer. This discovery led to the adoption of a bi‐interface optimization approach. A thin layer of Sn metal was inserted at the two surfaces of the perovskite layer. The implementation of this intervention yielded a significant decrease in the levels of Sn4+ and trap densities. The power conversion efficiency of the device was achieved at 14.31 % through the optimization of carrier transportation. The device exhibited operational and long‐term stability. [ABSTRACT FROM AUTHOR]

The photoelectric properties of nontoxic Sn‐based perovskite make it a promising alternative to toxic Pb‐based perovskite. It has superior photovoltaic performance in comparison to other Pb‐free counterparts. The facile oxidation of Sn2+ to Sn4+ presents a notable obstacle in the advancement of perovskite solar cells that utilize Sn, as it adversely affects their stability and performance. The study revealed the presence of a Sn4+ concentration on both the upper and lower surfaces of the perovskite layer. This discovery led to the adoption of a bi‐interface optimization approach. A thin layer of Sn metal was inserted at the two surfaces of the perovskite layer. The implementation of this intervention yielded a significant decrease in the levels of Sn4+ and trap densities. The power conversion efficiency of the device was achieved at 14.31 % through the optimization of carrier transportation. The device exhibited operational and long‐term stability. [ABSTRACT FROM AUTHOR]

The photoelectric properties of nontoxic Sn‐based perovskite make it a promising alternative to toxic Pb‐based perovskite. It has superior photovoltaic performance in comparison to other Pb‐free counterparts. The facile oxidation of Sn2+ to Sn4+ presents a notable obstacle in the advancement of perovskite solar cells that utilize Sn, as it adversely affects their stability and performance. The study revealed the presence of a Sn4+ concentration on both the upper and lower surfaces of the perovskite layer. This discovery led to the adoption of a bi‐interface optimization approach. A thin layer of Sn metal was inserted at the two surfaces of the perovskite layer. The implementation of this intervention yielded a significant decrease in the levels of Sn4+ and trap densities. The power conversion efficiency of the device was achieved at 14.31 % through the optimization of carrier transportation. The device exhibited operational and long‐term stability. [ABSTRACT FROM AUTHOR]

Precise detection of early osteolytic metastases is crucial for their treatment but remains challenging in the clinic because of the limited sensitivity and specificity of traditional imaging techniques. Although fluorescence imaging offers attractive features for the diagnosis of osteolytic metastases, it is hampered by limited penetration depth. To address this issue, a fluoro‐photoacoustic dual‐modality imaging probe comprising a near‐infrared dye caged by a cathepsin K (CTSK)‐cleavable peptide sequence on one side and functionalized with osteophilic alendronate through a polyethylene glycol linker on the other side is reported. Through systematic in vitro and in vivo experiments, it is demonstrated that in response to CTSK, the probe generated both near‐infrared fluorescent and photoacoustic signals from bone metastatic regions, thus offering a potential strategy for detecting deep‐seated early osteolytic metastases. [ABSTRACT FROM AUTHOR]

Fluorescence imaging in the second near‐infrared (NIR‐II) window holds great promise for in vivo visualization of amyloid‐β (Aβ) pathology, which can facilitate characterization and deep understanding of Alzheimer's disease (AD); however, it has been rarely exploited. Herein, we report the development of NIR‐II fluorescent reporters with a donor‐π‐acceptor (D‐π‐A) architecture for specific detection of Aβ plaques in AD‐model mice. Among all the designed probes, DMP2 exhibits the highest affinity to Aβ fibrils and can specifically activate its NIR‐II fluorescence after binding to Aβ fibrils via suppressed twisted intramolecular charge transfer (TICT) effect. With suitable lipophilicity for ideal blood–brain barrier (BBB) penetrability and deep‐tissue penetration of NIR‐II fluorescence, DMP2 possesses specific detection of Aβ plaques in in vivo AD‐model mice. Thus, this study presents a potential agent for non‐invasive imaging of Aβ plaques and deep deciphering of AD progression. [ABSTRACT FROM AUTHOR]

Developing smart molecular probes for assisting surgeons to precisely detect cancerous tissues and to completely remove all of them during the surgery is urgently required. Conventional fluorescent probes allow for tumor detection but with limited signal‐to‐noise ratio. Herein, an aminopeptidase N/CD13 (APN)‐activated chemiluminescent probe (APN‐ACLP) is reported for sensitive imaging and precise resection of malignant tumors. The APN‐ACLP probe is based on acryl‐substituted phenoxy‐dioxetane that is coupled with an APN‐cleavable substrate via a self‐immolative linker. Upon activation by APN through specific hydrolysis reaction, APN‐ACLP generates spontaneously chemiluminescence signal, which offers a possibility to sensitively search tumors by simply spraying APN‐ACLP on the suspicious sites. Animal imaging studies reveal that a sufficient signal contrast between the cancerous tissues and the normal counterparts can be achieved within 5 min, which can allow for rapid detection and surgical resection of tumors, particularly tiny metastatic lesions in mice model, under the guidance of chemiluminescence imaging, well manifesting its potential for image‐guided surgery of malignant tumors. [ABSTRACT FROM AUTHOR]

Imaging to evaluate tumor‐associated neutrophils (TANs) is imperative for cancer immunotherapy but remains challenging. We herein report an activatable semiconducting polymer nanoprobe (SPCy) for near‐infrared fluorescence (NIRF) and photoacoustic (PA) imaging of neutrophil elastase (NE), a biomarker of TANs. SPCy comprises a semiconducting polymer conjugated with a hemicyanine (hemi‐Cy) dye caged by a NE‐cleavable peptide as the side chain. After systemic administration, SPCy passively targets the tumor and reacts with NE to "uncage" the hemi‐Cy, leading to enhanced NIRF and PA signals of the hemi‐Cy but unchanged signals of the SP. Such NE‐activated ratiometric NIRF and enhanced PA signals of SPCy correlate with the intratumoral population of TANs. Thus, this study not only presents the first TAN‐specific PA probe, but also provides a general molecular design strategy for PA imaging of other immune‐related biomarkers to facilitate screening of cancer immunotherapeutics. [ABSTRACT FROM AUTHOR]

The article titled "Revealing the Roles of Guanidine Hydrochloride Ionic Liquid in Ion Inhibition and Defects Passivation for Efficient and Stable Perovskite Solar Cells" explores the use of guanidine-based ionic liquids in improving the crystallization kinetics and stability of perovskites and perovskite-based devices. The study found that guanidine hydrochloride can passivate intrinsic defects in organic-inorganic metal halide perovskites through hydrogen bonds and coordinate bonds. The front cover of the journal illustrates the connection between solar energy, perovskite solar cells, and ionic liquids. The research article provides more detailed information on the topic. [Extracted from the article]

Development of real‐time non‐invasive imaging probes to assess infiltration and activation of cytotoxic T cells (CTLs) is critical to predict the efficacy of cancer immunotherapy, which however remains challenging. Reported here is an activatable semiconducting polymer nanoprobe (SPNP) for near‐infrared fluorescence (NIRF) and photoacoustic (PA) imaging of a biomarker (granzyme B) associated with activation of CTLs. SPNP comprises a semiconducting polymer (SP) conjugated with a granzyme B cleavable and dye‐labeled peptide as the side chain, both of which emit NIRF and PA signals. After systemic administration, SPNP passively targets the tumor and in situ reacts with granzyme B to release the dye‐labeled peptide, leading to decreased NIRF and PA signals from the dye but unchanged signals from the polymer. Such ratiometric NIRF and PA signals of SPNP correlate well with the expression level of granzyme B and intratumoral population of CTLs. Thus, this study not only presents the first PA probes for in vivo imaging of immune activation but also provides a molecular design strategy that can be generalized for molecular imaging of other immune‐related biomarkers. [ABSTRACT FROM AUTHOR]

Discriminative detection of invasive and noninvasive breast cancers is crucial for their effective treatment and prognosis. However, activatable probes able to do so in vivo are rare. Herein, we report an activatable polymeric reporter (P‐Dex) that specifically turns on near‐infrared (NIR) fluorescent and photoacoustic (PA) signals in response to the urokinase‐type plasminogen activator (uPA) overexpressed in invasive breast cancer. P‐Dex has a renal‐clearable dextran backbone that is linked with a NIR dye caged with an uPA‐cleavable peptide substrate. Such a molecular design allows P‐Dex to passively target tumors, activate NIR fluorescence and PA signals to effectively distinguish invasive MDA‐MB‐231 breast cancer from noninvasive MCF‐7 breast cancer, and ultimately undergo renal clearance to minimize the toxicity potential. Thus, this polymeric reporter holds great promise for the early detection of malignant breast cancer. [ABSTRACT FROM AUTHOR]

Abstract: Theranostics provides opportunities for precision cancer therapy. However, theranostic probes that simultaneously turn on their diagnostic signal and pharmacological action only in respond to a targeted biomarker have been less exploited. We herein report the synthesis of a macrotheranostic probe that specifically activates its near‐infrared fluorescence (NIRF), photoacoustic (PA), and photothermal signals in the presence of a cancer‐overexpressed enzyme for imaging‐guided cancer therapy. Superior to the small‐molecule counterpart probe, the macrotheranostic probe has ideal biodistribution and renal clearance, permitting passive targeting of tumors, in situ activation of multimodal signals, and effective photothermal ablation. Our study thus provides a macromolecular approach towards activatable multimodal phototheranostics. [ABSTRACT FROM AUTHOR]

Abstract: Regulation of enzyme activity is fundamentally challenging but practically meaningful for biology and medicine. However, noninvasive remote control of enzyme activity in living systems has been rarely demonstrated and exploited for therapy. Herein, we synthesize a semiconducting polymer nanoenzyme with photothermic activity for enhanced cancer therapy. Upon near‐infrared (NIR) light irradiation, the activity of the nanoenzyme can be enhanced by 3.5‐fold to efficiently digest collagen in the tumor extracellular matrix (ECM), leading to enhanced nanoparticle accumulation in tumors and consequently improved photothermal therapy (PTT). This study thus provides a promising strategy to remotely regulate enzyme activity for cancer therapy. [ABSTRACT FROM AUTHOR]

Abstract: Early detection of skin diseases is imperative for their effective treatment. However, fluorescence molecular probes that allow this are rare. The first activatable near‐infrared (NIR) fluorescent molecular probe is reported for sensitive imaging of keloid cells, skin cells from abnormal scar fibrous lesions. As keloid cells have high expression levels of fibroblast activation protein‐alpha (FAPα), the probe (FNP1) is designed to have a caged NIR dye and a FAPα‐cleavable peptide substrate linked by a self‐immolative segment. FNP1 can quickly and specifically turn on its fluorescence at 710 nm by 45‐fold in the presence of FAPα, allowing it to effectively recognize keloid cells from normal skin cells. Integration of FNP1 with a simple microneedle‐assisted topical application enables sensitive detection of keloid cells in metabolically‐active human skin tissue with a theoretical limit of detection down to 20 000 cells. [ABSTRACT FROM AUTHOR]

Keywords: activatable probe; cancer; near-infrared fluorescent probes; polymers; photoacoustic imaging EN activatable probe cancer near-infrared fluorescent probes polymers photoacoustic imaging 7005 7005 1 04/22/20 20200427 NES 200427 B Ein aktivierbarer polymerer Reporter b (P-Dex), der durch Nahinfrarot-Fluoreszenz und photoakustische Signale auf einen Biomarker (uPA) anspricht, wurde gezielt entworfen. GLO:OL3/27apr20:ange202003878-gra-0001.jpg PHOTO (COLOR): . gl B Nanographen b E. Maçôas, A. G. Campaña et al. zeigen in ihrem Forschungsartikel auf S. 7205, wie die Einführung eines Troponrings in ein Nanographenband die Upconversion-Emission verstärkt. Activatable probe, cancer, near-infrared fluorescent probes, polymers, photoacoustic imaging. [Extracted from the article]