Molecular Engineering of Terminus, Conjugation, and Energetics for Thermally Stable Inverted Perovskite Solar Cells.

Low-dimensional (LD)/three-dimensional (3D) heterostructure perovskite solar cells (PSCs) have achieved a power conversion efficiency (PCE) greater than 26%. However, the use of some ionic interfacial passivation materials in the construction of LD perovskites compromises device stability, as they can induce ion diffusion, particularly under high temperatures and light stress. In this study, we substitute the ammonium terminus (R-NH) of conventional passivators with a carbamate terminus (R-NH-(CO)OR) and synthesized carbamate molecules featuring phenyl (PEA-Boc) and naphthalimide (ND-Boc) scaffolds.

Solid-State Packing Controls Exciton Delocalization and Photophysics in Nonfullerene Acceptors.

We engineer molecular packing in five derivatives of the nonfullerene acceptor Y6. Using transient absorption spectroscopy, we find evidence of the formation of a delocalized exciton in addition to the local exciton in neat films of the acceptors. Following selective photoexcitation of the acceptors in donor/acceptor blends with D18, we observe anion formation on the same timescale as in neat acceptor films, suggesting that D18 is a bystander to charge generation after photoexcitation of the acceptors.

Integration of hyperspectral imaging and transcriptomics from individual cells with SpectralSeq.

Microscopy and omics are complementary approaches to probe cellular molecular states in health and disease, combining granularity with scalability. However, integrating both imaging- and sequencing-based assays on the same cell has proven challenging. This study demonstrates a new approach called SpectralSeq that combines hyperspectral autofluorescence imaging with transcriptomics on the same cell.

Galvanotactic directionality of cell groups depends on group size.

Motile cells migrate directionally in the electric field (EF) in a process known as galvanotaxis, an important phenomenon in wound healing and development. We previously reported that individual fish keratocyte cells migrate to the cathode in EFs, that inhibition of PI3 kinase (PI3K) reverses single cells to the anode, and that large cohesive groups of either unperturbed or PI3K-inhibited cells migrate to the cathode. Here, we report that small uninhibited cell groups move to the cathode, while small groups of PI3K-inhibited cells move to the anode.

Design of Intrinsically Stable Hole-Selective Self-Assembled Monolayers by Introducing Fused-Ring Intramolecular Donor-Acceptor Interactions.

Hole-selective self-assembled monolayers (SAMs) incorporating electron-donating conjugated units as head groups have witnessed remarkable success in helping achieve high-performance organic solar cells (OSCs). However, these molecules frequently exhibit a shallow lowest unoccupied molecular orbital (LUMO) level, rendering them prone to photodegradation. To tackle this problem, we introduce fused-ring intramolecular donor-acceptor (D-A) interactions into the design of SAM molecules to downshift the LUMO level.

Textured Inorganic Perovskite Interlayer Enhances Carrier Extraction for Organic Solar Cells.

The PEDOT:PSS has been utilized extensively as a hole transport layer (HTL) in organic solar cells (OSCs) due to its excellent compatibility with various bulk heterojunction (BHJ) active layers. However, its intrinsically low electrical conductivity and suboptimal surface morphology limit hole extraction, ultimately constraining the performance of OSCs. To address this, we constructed an advanced heterojunction interface by introducing a wide-bandgap perovskite (CsPbBr) interlayer between the PEDOT:PSS and BHJ.

Regiospecific Halogenation Modulates Molecular Dipoles in Self-Assembled Monolayers for High-Performance Organic Solar Cells.

Halogenated carbazole-derived self-assembled monolayers (SAMs) are promising hole-extraction materials in conventional organic solar cells (OSCs). While halogenation helps optimize the molecular dipole, intermolecular interactions, and energetics of SAM, the highly polarizable carbon-halogen bonds can be reactive and prone to photocleavage depending on their regiochemistry. Herein, we study the regiospecific properties, including the intrinsic stability, electrostatic potential (ESP) distribution, and changes in molecular dipole of the brominated SAM molecules by brominating a helical 7H-dibenzo[c,g]carbazole-based SAM (CbzNaph) featuring a stronger dipole.

Photoluminescent delocalized excitons in donor polymers facilitate efficient charge generation for high-performance organic photovoltaics.

Efficient delocalization of photo-generated excitons is a key to improving the charge-separation efficiencies in state-of-the-art organic photovoltaic (OPV) absorber. While the delocalization in non-fullerene acceptors has been widely studied, we expand the scope by studying the properties of the conjugated polymer donor D18 on both the material and device levels. Combining optical spectroscopy, X-ray diffraction, and simulation, we show that D18 exhibits stronger π-π interactions and interchain packing compared to classic donor polymers, as well as higher external photoluminescence quantum efficiency (~26%).

A passive flow microreactor for urine creatinine test.

Chronic kidney disease (CKD) significantly affects people's health and quality of life and presents a high economic burden worldwide. There are well-established biomarkers for CKD diagnosis. However, the existing routine standard tests are lab-based and governed by strict regulations.

Balancing carrier transport in interconnection layer for efficient perovskite/organic tandem solar cells.

While individual perovskite and organic solar cells have demonstrated remarkable performance, achieving similar success in high-efficiency perovskite/organic tandem solar cells (TSCs) has been challenging, primarily due to large voltage deficits and severe non-radiative recombination. By exploring the fundamental mechanisms of carrier losses, we identify that imbalanced carrier transport, particularly inadequate hole transport in the organic subcell significantly limits the overall performance of perovskite/organic TSCs. Herein, we implement a hole transport self-assembled monolayer (SAM) anchored to MoO, which converts the inherently n-type MoO to a p-type surface.

Supramolecular force-driven non-fullerene acceptors as an electron-transporting layer for efficient inverted perovskite solar cells.

Fullerene derivatives are widely employed as efficient electron-transporting layers (ETLs) in p-i-n perovskite photovoltaics but face challenges in mitigating interfacial recombination losses and ensuring stable film morphology. Non-fullerene acceptors (NFAs), commonly utilized in organic photovoltaics, present a promising alternative to fullerene-based ETLs. Nevertheless, the suboptimal performance of NFA-based devices underscores the need for molecular engineering to tailor their properties.

Donor-Interacting Arylated Carbazole Self-Assembled Monolayer Enables Highly Efficient and Stable Organic Photovoltaics.

Carbazole-derived self-assembled monolayers (SAMs) are promising materials for hole-extraction layer (HEL) in conventional organic photovoltaics (OPVs). Here, a SAM Cbz-2Ph derived from 3,6-diphenylcarbazole is demonstrated. The large molecular dipole moment of Cbz-2Ph allows the modulation of electrode work function to facilitate hole extraction and maximize photovoltage, thus improving the OPV performance.

Buried Interface Modification Toward Efficient CsPbIBr Based Monolithic Perovskite/Organic Tandem Solar Cells.

Wide-bandgap perovskite sub-cells (WPSCs), one of the most crucial components of perovskite-based tandem solar cells (PTSCs), play a critical role in determining the performance of tandem devices. However, confined by the compromised crystallization properties of wide-bandgap perovskites, WPSCs exhibit significantly lower efficiency than their theoretical limit. In particular, for n-i-p structured all-inorganic WPSCs (AIWPSCs), severe nonradiative recombination due to the buried interface defects severely decreases the photovoltaic performance.

Galvanotactic directionality of cell groups depends on group size.

Motile cells migrate directionally in the electric field in a process known as galvanotaxis, important and under-investigated phenomenon in wound healing and development. We previously reported that individual fish keratocyte cells migrate to the cathode in electric fields, that inhibition of PI3 kinase reverses single cells to the anode, and that large cohesive groups of either unperturbed or PI3K-inhibited cells migrate to the cathode. Here we find that small uninhibited cell groups move to the cathode, while small groups of PI3K-inhibited cells move to the anode.

Accelerating Proteomics Using Broad Specificity Proteases.

Trypsin is the gold-standard protease in bottom-up proteomics, but many sequence stretches of the proteome are inaccessible to trypsin and standard LC-MS approaches. Thus, multienzyme strategies are used to maximize sequence coverage in post-translational modification profiling. We present fast and robust SP3- and STRAP-based protocols for the broad-specificity proteases subtilisin, proteinase K, and thermolysin.