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To date, perovskite solar cells (pero‐SCs) with doped 2,2′,7,7′‐tetrakis(N,N‐di‐p‐methoxyphenylamine)‐9,9′‐spirobifluorene (Spiro‐OMeTAD) hole transporting layers (HTLs) have shown the highest recorded power conversion efficiencies (PCEs). However, their commercialization is still impeded by poor device stability owing to the hygroscopic lithium bis(trifluoromethanesulfonyl)imide and volatile 4‐tert‐butylpyridine dopants as well as time‐consuming oxidation in air. In this study, we explored a series of single‐component iodonium initiators with strong oxidability and different electron delocalization properties to precisely manipulate the oxidation states of Spiro‐OMeTAD without air assistance, and the oxidation mechanism was clearly understood. Iodine (III) in the diphenyliodonium cation (IP+) can accept a single electron from Spiro‐OMeTAD and forms Spiro‐OMeTAD⋅+ owing to its strong oxidability. Moreover, because of the coordination of the strongly delocalized TFSI− with Spiro‐OMeTAD⋅+ in a stable radical complex, the resulting hole mobility was 30 times higher than that of pristine Spiro‐OMeTAD. In addition, the IP‐TFSI initiator facilitated the growth of a homogeneous and pinhole‐free Spiro‐OMeTAD film. The pero‐SCs based on this oxidizing HTL showed excellent efficiencies of 25.16 % (certified: 24.85 % for 0.062‐cm2) and 20.71 % for a 15.03‐cm2 module as well as remarkable overall stability. [ABSTRACT FROM AUTHOR]

To date, perovskite solar cells (pero‐SCs) with doped 2,2′,7,7′‐tetrakis(N,N‐di‐p‐methoxyphenylamine)‐9,9′‐spirobifluorene (Spiro‐OMeTAD) hole transporting layers (HTLs) have shown the highest recorded power conversion efficiencies (PCEs). However, their commercialization is still impeded by poor device stability owing to the hygroscopic lithium bis(trifluoromethanesulfonyl)imide and volatile 4‐tert‐butylpyridine dopants as well as time‐consuming oxidation in air. In this study, we explored a series of single‐component iodonium initiators with strong oxidability and different electron delocalization properties to precisely manipulate the oxidation states of Spiro‐OMeTAD without air assistance, and the oxidation mechanism was clearly understood. Iodine (III) in the diphenyliodonium cation (IP+) can accept a single electron from Spiro‐OMeTAD and forms Spiro‐OMeTAD⋅+ owing to its strong oxidability. Moreover, because of the coordination of the strongly delocalized TFSI− with Spiro‐OMeTAD⋅+ in a stable radical complex, the resulting hole mobility was 30 times higher than that of pristine Spiro‐OMeTAD. In addition, the IP‐TFSI initiator facilitated the growth of a homogeneous and pinhole‐free Spiro‐OMeTAD film. The pero‐SCs based on this oxidizing HTL showed excellent efficiencies of 25.16 % (certified: 24.85 % for 0.062‐cm2) and 20.71 % for a 15.03‐cm2 module as well as remarkable overall stability. [ABSTRACT FROM AUTHOR]

The doped Spiro‐OMeTAD hole transport layer (HTL) formed using the lithium bis(trifluoromethane) sulfonimide salt and 4‐tert‐butylpyridine with phenethylammonium iodide surface treatment on a perovskite film has continuously dominated the record power conversion efficiencies (PCEs) of perovskite solar cells (pero‐SCs). However, unstable HTL compositions and iodide salts can cause severe device degradation. In this study, an HTL composition‐conditioning agent (CCA), Spiro‐BD‐2OEG, is designed, which contains a Spiro‐OMeTAD‐like backbone, functional pyridine units, and oligo (ethylene glycol) chains. This finely designed CCA presents good miscibility with Spiro‐OMeTAD and its dopants and acts as a conditioning agent through weak bond interactions. As a result, the CCA‐regulated HTL shows a pinhole‐free and smooth morphology with enhanced Spiro‐OMeTAD ordering and improves dopant stability. In addition, the gradient‐distributed CCA in the HTL can narrow the energy level offset with the valence band of the perovskite. The resultant pero‐SCs exhibit an excellent PCE of 24.19% without any interface treatment and weak size dependence. A remarkable PCE of 22.63% is obtained even for a 1.004‐cm2 device. Importantly, the strategy shows good universality and significantly promotes the long‐term stability of the pero‐SCs based on the classical doped Spiro‐OMeTAD. [ABSTRACT FROM AUTHOR]

Museums displaying artifacts of the human struggle against oppression are often caught in their own internal struggle between presenting factual and unbiased descriptions of their collections, or relying on testament of survivors. Often this quandary is resolved in favor of what can be verified, not what is remembered. However, with improving instrumentation, methods and informatic approaches, science can help uncover evidence able to reconcile memory and facts. Following World War II, thousands of small, cement-like disks with numbers impressed on one side were found at concentration camps throughout Europe. Survivors claimed these disks were made of human cremains; museums erred on the side of caution—without documentation of the claims, was it justifiable to present them as fact? The ability to detect species relevant biological material in these disks could help resolve this question. Proteomic mass spectrometry of five disks revealed all contained proteins, including collagens and hemoglobins, suggesting they were made, at least in part, of animal remains. A new protein/informatics approach to species identification showed that while human was not always identified as the top contributor, human was the most likely explanation for one disk. To our knowledge, this is the first demonstration of protein recovery from cremains. Data are available via ProteomeXchange with identifier PXD035267. [ABSTRACT FROM AUTHOR]

Organic materials with excitation wavelength‐dependent (Ex‐de) emission are highly attractive for anticounterfeiting, optoelectronics and bioassay applications; however, the realization of Ex‐de fluorescence, independent of aggregation states, remains a challenge. We herein report a photoinduced electron transfer (PeT) strategy to design Ex‐de fluorescence materials by manipulating the relaxation pathways of multiple excited states. As expected, the o‐carborane dyad presents a clear Ex‐de fluorescence colour in the aggregated states, resulting from the tunable relative intensity of the dual‐fluorescence spectra. Taking TP[1]B as an example, the amorphous powders emitted bright blue‐violet, white and yellow colours under 390 nm, 365 nm and 254 nm UV illumination, respectively. Importantly, multicolour, flexible and transparent films as well as an anticounterfeiting application using this o‐carborane dyad are demonstrated. [ABSTRACT FROM AUTHOR]

Organic materials with excitation wavelength‐dependent (Ex‐de) emission are highly attractive for anticounterfeiting, optoelectronics and bioassay applications; however, the realization of Ex‐de fluorescence, independent of aggregation states, remains a challenge. We herein report a photoinduced electron transfer (PeT) strategy to design Ex‐de fluorescence materials by manipulating the relaxation pathways of multiple excited states. As expected, the o‐carborane dyad presents a clear Ex‐de fluorescence colour in the aggregated states, resulting from the tunable relative intensity of the dual‐fluorescence spectra. Taking TP[1]B as an example, the amorphous powders emitted bright blue‐violet, white and yellow colours under 390 nm, 365 nm and 254 nm UV illumination, respectively. Importantly, multicolour, flexible and transparent films as well as an anticounterfeiting application using this o‐carborane dyad are demonstrated. [ABSTRACT FROM AUTHOR]

Proteogenomics is an increasingly common method for species identification as it allows for rapid and inexpensive interrogation of an unknown organism's proteome—even when the proteome is partially degraded. The proteomic method typically uses tandem mass spectrometry to survey all peptides detectable in a sample that frequently contains hundreds or thousands of proteins. Species identification is based on detection of a small numbers of species-specific peptides. Genetic analysis of proteins by mass spectrometry, however, is a developing field, and the bone proteome, typically consisting of only two proteins, pushes the limits of this technology. Nearly 20% of highly confident spectra from modern human bone samples identify non-human species when searched against a vertebrate database—as would be necessary with a fragment of unknown bone. These non-human peptides are often the result of current limitations in mass spectrometry or algorithm interpretation errors. Consequently, it is difficult to know if a "species-specific" peptide used to identify a sample is actually present in that sample. Here we evaluate the causes of peptide sequence errors and propose an unbiased, probabilistic approach to determine the likelihood that a species is correctly identified from bone without relying on species-specific peptides. [ABSTRACT FROM AUTHOR]

Fe3+‐doped MgGa2O4 (MGO: Fe3+) spinel‐type near‐infrared (NIR) phosphor with non‐toxicity, outstanding thermal stability, and tunable emission has recently gained great concern owing to its wide applications. Nevertheless, the existence of detrimental O defects in the MgGa2O4 host and the forbidden d‐d transitions of Fe3+ lead to unsatisfactory luminescence efficiency, limiting the commercial application. In this study, a vacancy repairing engineering has been innovatively developed via F− substitution in MGO: Fe3+ (MGOF: Fe3+) for significantly enhancing NIR emission and maintaining outstanding thermal stability. Specifically, F− substitution with a similar radius effectively repairs the intrinsic O vacancy defects of MGO, thereby prohibiting the detrimental electron‐capturing effect. Meanwhile, F− incorporation can make the lattice of MGO distort and break the forbidden transition of Fe3+. Significantly, the obtained MGOF: Fe3+ presents a 16‐fold higher emission intensity than that of MGO: Fe3+. More important, the MGOF: Fe3+ can remain at 91.17% (363 K) and 85.10% (423 K). Finally, the NIR emission of MGOF: Fe3+ can be used for night vision, non‐destructive biological tissue detection, and food analysis. The proposed vacancy repairing strategy can certainly stimulate some new thoughts and concepts in designing high‐performance phosphors for wider applications. [ABSTRACT FROM AUTHOR]

Excitation wavelength dependent (Ex‐De) emission materials have potential applications in anti‐counterfeiting labels and bioimaging. Nevertheless, few purely organic chromophores are used in these areas. In this study, multiple excited states were incorporated into a molecule that was excited state intramolecular proton transfer (ESIPT) active, with the goal of manipulating the relaxation pathways of the excited states. The triazole derivative exhibits Ex‐De photoluminescence (PL), and the maximum PL wavelength is located at 526 nm and 593 nm under a series of excitation wavelengths. Spectral identification indicates that the excimer and ESIPT processes are responsible for the green (526 nm) and orange (593 nm) fluorescence, respectively. Importantly, the quick response code and test strip prepared with this triazole derivative can be used for anti‐counterfeiting and food spoilage detection applications, respectively. This research opens the door for developing novel Ex‐De materials for anti‐counterfeiting purposes. [ABSTRACT FROM AUTHOR]

Excitation wavelength dependent (Ex‐De) emission materials have potential applications in anti‐counterfeiting labels and bioimaging. Nevertheless, few purely organic chromophores are used in these areas. In this study, multiple excited states were incorporated into a molecule that was excited state intramolecular proton transfer (ESIPT) active, with the goal of manipulating the relaxation pathways of the excited states. The triazole derivative exhibits Ex‐De photoluminescence (PL), and the maximum PL wavelength is located at 526 nm and 593 nm under a series of excitation wavelengths. Spectral identification indicates that the excimer and ESIPT processes are responsible for the green (526 nm) and orange (593 nm) fluorescence, respectively. Importantly, the quick response code and test strip prepared with this triazole derivative can be used for anti‐counterfeiting and food spoilage detection applications, respectively. This research opens the door for developing novel Ex‐De materials for anti‐counterfeiting purposes. [ABSTRACT FROM AUTHOR]

Standard methods for body fluid identification typically rely on detection of the functional proteins specific to or enriched in them, such as hemoglobin in blood, alkaline phosphatase and PSA in semen, or α-amylase in saliva. While these markers can be relatively specific, the multiple methods used to identify them frequently rely on nonspecific chemical, enzymatic, or antibody reactions that usually require the structural integrity of the markers and are not confirmatory because other proteins or substances can also give positive test results. Recent advances in proteomics and mass spectrometry offer the ability to simultaneously detect multiple body fluid protein markers in a single, confirmatory test. Here, multiple markers for blood, saliva, and semen are identified by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS). Data demonstrate the ability to detect these body fluids at nanoliter to subnanoliter levels and to distinguish mixtures. Protein stability of mock samples assayed after 16 months showed no diminution of signal. Because multiple peptides from multiple protein markers are detected and effectively sequenced by MALDI MS/MS, the assay is confirmatory. As mass spectrometry detects whatever peptides are present in a sample, no a priori knowledge of an unknown stain is necessary to perform the test. [ABSTRACT FROM AUTHOR]

A robust high-throughput single-nucleotide polymorphism (SNP) genotyping method is reported, which applies allele-specific extension to achieve allelic discrimination and uses matrix-assisted laser desorption/ionization time-of-flight mass spectrometry to measure the natural molecular weight difference of oligonucleotides for determination of the base in a single-nucleotide polymorphic location. Tenfold PCR is performed successfully by carefully designing the primers and adjusting the conditions of PCR. In addition, two ways used for PCR product purification are compared and the matrix used in mass spectrometry for high-throughput oligonucleotide analysis is evaluated. The result here shows that the method is very effective and suitable for high-throughput genotyping of SNPs. [Copyright &y& Elsevier]

A decline in atmospheric oxygen concentration is projected in the 21st century given the background of global warming. The Qinghai-Tibetan Plateau is located at a high altitude, and thus, it faces a hypoxia challenge; however, knowledge of the factors contributing to its atmospheric oxygen concentration is still lacking. Here, we conducted joint observations of ecosystem oxygen production and carbon sinks and near-surface atmospheric oxygen concentrations on the Qinghai-Tibetan Plateau and meteorological elements at Beijing Fangshan Station. Using seasonal differences and statistical methods, we calculated the relative contribution rates of vegetation to changes in atmospheric oxygen concentration. Our results indicate that solar radiation, atmospheric humidity, and ecosystem oxygen consumption and production have a significant impact on the atmospheric oxygen concentration, and the impact shows temporal and spatial differences. Vegetation significantly impacts the oxygen concentration, with a contribution rate of 16.7%–24.5%, which is underestimated in existing research. Our findings provide important insights into the factors that influence atmospheric oxygen concentration and highlight the contribution of vegetation. To better understand the oxygen dynamics of the Qinghai-Tibetan Plateau, we recommend further field observations of soil respiration and vegetation photosynthesis to clarify the contributions of carbon storage, carbon sinks and other factors to the near-surface atmospheric oxygen concentration. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The power conversion efficiencies (PCEs) of all‐polymer solar cells (all‐PSCs), usually processed from low‐boiling‐point and toxic solvents, have reached high values of 18%. However, poor miscibility and uncontrollable crystallinity in polymer blends lead to a notable drop in the PCEs when using green solvents, limiting the practical development of all‐PSCs. Herein, a third component (guest) BTO was employed to optimize the miscibility and enhance the crystallinity of PM6/PY2Se‐F host film processed from green solvent toluene (TL), which can effectively suppress the excessive aggregation of PY2Se‐F and facilitate a nano‐scale interpenetrating network morphology for exciton dissociation and charge transport. As a result, TL‐processed all‐polymer hosted solar cells (all‐PHSCs) exhibited an impressive PCE of 17.01%. Moreover, the strong molecular interaction between the host and guest molecules also enhances the thermal stability of the devices. Our host‐guest strategy provides a unique approach to developing high‐efficiency and stable all‐PHSCs processed from green solvents, paving the way for the industrial development of all‐PHSCs. [ABSTRACT FROM AUTHOR]

The stability‐related issues arising from the perovskite precursor inks, films, device structures and interdependence remain severely under‐explored to date. Herein, we designed an ionic‐liquid polymer (poly[Se‐MI][BF4]), containing functional moieties like carbonyl (C=O), selenium (Se+), and tetrafluoroborate (BF4−) ions, to stabilize the whole device fabrication process. The C=O and Se+ can coordinate with lead and iodine (I−) ions to stabilize lead polyhalide colloids and the compositions of the perovskite precursor inks for over two months. The Se+ anchored on grain boundaries and the defects passivated by BF4− efficiently suppress the dissociation and migration of I− in perovskite films. Benefiting from the synergistic effects of poly[Se‐MI][BF4], high efficiencies of 25.10 % and 20.85 % were exhibited by a 0.062‐cm2 device and 15.39‐cm2 module, respectively. The devices retained over 90 % of their initial efficiency under operation for 2200 h. [ABSTRACT FROM AUTHOR]

The stability‐related issues arising from the perovskite precursor inks, films, device structures and interdependence remain severely under‐explored to date. Herein, we designed an ionic‐liquid polymer (poly[Se‐MI][BF4]), containing functional moieties like carbonyl (C=O), selenium (Se+), and tetrafluoroborate (BF4−) ions, to stabilize the whole device fabrication process. The C=O and Se+ can coordinate with lead and iodine (I−) ions to stabilize lead polyhalide colloids and the compositions of the perovskite precursor inks for over two months. The Se+ anchored on grain boundaries and the defects passivated by BF4− efficiently suppress the dissociation and migration of I− in perovskite films. Benefiting from the synergistic effects of poly[Se‐MI][BF4], high efficiencies of 25.10 % and 20.85 % were exhibited by a 0.062‐cm2 device and 15.39‐cm2 module, respectively. The devices retained over 90 % of their initial efficiency under operation for 2200 h. [ABSTRACT FROM AUTHOR]

C16H14O5, monoclinic, P21/c (no. 14), a = 11.1420(17) Å, b = 8.4700(12) Å, c = 15.429(2) Å, β = 104.624(4)°, V = 1408.9(4) Å3, Z = 4, Rgt(F) = 0.0513, wRref(F2) = 0.1243, T = 296(2) K. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Recent advances in non‐fullerene acceptors (NFAs) like Y6 have pushed the power conversion efficiencies (PCEs) of organic solar cells (OSCs) above 19%. However, the harsh fabrication conditions, such as the use of the highly volatile chloroform (CF) solvent and the thermal annealing process, are not suitable for large‐area printing technologies and environmental standards. Here, a series of guest molecules, BT2O, BTO, and BT4O, are designed and synthesized with different numbers of oligo ethylene glycol (OEG) repeating units in side chains. All these guest molecules could tune the crystallization kinetics of the annealing‐free host‐guest active layers by inducing the self‐assembly of Y6 in non‐halogenated paraxylene (PX) solution. The increasing number of OEG repeating units in guest molecules could enhance the molecular assembly ability but molecular stacking steric hindrance simultaneously. Therefore, BTO with three OEG repeating units blended with PM6:PM7:Y6 delivers the highest PCE of 17.78%. Our results demonstrate controlling the crystallization kinetics via delicate side‐chain engineering of guest molecules is an effective way to achieve efficient OSCs in non‐halogenated solution. [ABSTRACT FROM AUTHOR]

Dopant‐free organic hole transport materials (HTMs) remain highly desirable for stable and efficient n‐i‐p perovskite solar cells (pero‐SCs) but rarely succeed. Here, we propose a molecular assembly strategy to overcome the limited optoelectronic properties of organic HTMs by precisely designing a linear organic small molecule BDT‐DPA‐F from the atomic to the molecular levels. BDT‐DPA‐F can assemble into a fibril network, showing an obviously improved hole mobility and decreased energy disorder. The resultant pero‐SCs showed a promising efficiency of 23.12 % (certified 22.48 %), which is the highest certified value of pero‐SCs with dopant‐free HTMs, to date. These devices also showed a weak‐dependence of efficiency on size, enabling a state‐of‐the‐art efficiency of 22.50 % for 1‐cm2 device and 20.17 % for 15.64‐cm2 module. For the first time, the pero‐SCs based on dopant‐free HTMs realized ultralong stabilities with T80 lifetimes over 1200 h under operation or thermal aging at 85 °C. [ABSTRACT FROM AUTHOR]

Dopant‐free organic hole transport materials (HTMs) remain highly desirable for stable and efficient n‐i‐p perovskite solar cells (pero‐SCs) but rarely succeed. Here, we propose a molecular assembly strategy to overcome the limited optoelectronic properties of organic HTMs by precisely designing a linear organic small molecule BDT‐DPA‐F from the atomic to the molecular levels. BDT‐DPA‐F can assemble into a fibril network, showing an obviously improved hole mobility and decreased energy disorder. The resultant pero‐SCs showed a promising efficiency of 23.12 % (certified 22.48 %), which is the highest certified value of pero‐SCs with dopant‐free HTMs, to date. These devices also showed a weak‐dependence of efficiency on size, enabling a state‐of‐the‐art efficiency of 22.50 % for 1‐cm2 device and 20.17 % for 15.64‐cm2 module. For the first time, the pero‐SCs based on dopant‐free HTMs realized ultralong stabilities with T80 lifetimes over 1200 h under operation or thermal aging at 85 °C. [ABSTRACT FROM AUTHOR]

We propose a dielectric-screening-enhancement effect for perovskite defects by using high dielectric constant organic semiconductors, thus considerably suppressing nonradiative recombination beyond defect passivation. More importantly, organic–inorganic hybrid pero-SCs with robust stabilities exhibited boosted PCEs of 23.35% (0.062 cm2) and 21.93% (1 cm2), showing less dependence. [Display omitted] Perovskite solar cells (pero-SCs) performance is essentially limited by severe non-radiative losses and ion migration. Although numerous strategies have been proposed, challenges remain in the basic understanding of their origins. Here, we report a dielectric-screening-enhancement effect for perovskite defects by using organic semiconductors with finely tuned molecular structures from the atoms level. Our method produced various perovskite films with high dielectric constant values, reduced charge capture regions, suppressed ion migration, and it provides an efficient charge transport pathway for suppressing non-radiative recombination beyond the passivation effect. The resulting pero-SCs showed a promising power conversion efficiency (PCE) of 23.35% with a high open-circuit voltage (1.22 V); and the 1-cm2 pero-SCs maintained an excellent PCE (21.93%), showing feasibility for scalable fabrication. The robust operational and thermal stabilities revealed that this method paved a new way to understand the degradation mechanism of pero-SCs, promoting the efficiency, stability and scaled fabrication of the pero-SCs. [ABSTRACT FROM AUTHOR]

The detection and sensing of acidic gases by optical sensors are of great importance in the fields of chemistry, environment and related industrial process. However, stretchable, low-cost, and tailorable sensors with high sensitivity and fast response remain a great challenge. In this work, we report a twisting donor–acceptor fluorophore ( DBPA ) with a hybridized local and charge-transfer excited state ( HLCT ) can serve as a visible dual-channel (colorimetric and fluorometric) sensor towards acid gas detection. Combination of the locally excited ( LE ) state and the high sensitive charge-transfer ( CT ) state, DBPA in aggregated state presents a high PL efficiency ( η PL > 76%), which exhibits over 98% PL quenching and a clear color difference ( ΔE over 20 ) upon exposure to HCl gas. By incorporation of HLCT -active DBPA molecule into an elastomer host through an electrospinning process, new flexible and stretchable nanofiber films ( SNMs ) were prepared. Compared to non-porous rigid films, the sensitivity and response time of SNMs were obviously improved due to their large surface area and high porosity. It can be expected that, by taking the advantages of easy mass-production and low cost, such SNMs could be a promising optical material for practical sensory application. [ABSTRACT FROM AUTHOR]

Phosphorylation of the Kir3 channel by cAMP-dependent protein kinase (PKA) potentiates activity and strengthens channel–PIP2 interactions, whereas phosphorylation by protein kinase C (PKC) exerts the opposite effects (Keselman et al., Channels 1:113–123, ; Lopes et al., Channels 1:124–134, ). Unequivocal identification of phosphorylated residues in ion channel proteins has been difficult, but recent advances in mass spectrometry techniques have allowed precise identification of phosphorylation sites (Park et al., Science 313:976–979, ). In this study, we utilized mass spectrometry to identify phosphorylation sites within the Kir3.1 channel subunit. We focused on the Kir3.1 C-terminal cytosolic domain that has been reported to be regulated by several modulators. In vitro phosphorylation by PKA exhibited a convincing signal upon treatment with a phosphoprotein stain. The phosphorylated C terminus was subjected to mass spectrometric analysis using matrix-assisted lased desorption/ionization–time of flight mass spectroscopy (MS). Peptides whose mass underwent a shift corresponding to addition of a phosphate group were then subjected to tandem MS (MS/MS) in order to confirm the modification and determine its precise location. Using this approach, we identified S385 as an in vitro phosphorylation site. Mutation of this residue to alanine resulted in a reduced sensitivity of Kir3.1* currents to H89 and Forskolin, confirming an in vivo role for this novel site of the Kir3.1 channel subunit in its regulation by PKA. [ABSTRACT FROM AUTHOR]