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Tissue-clearing and labeling techniques have revolutionized brain-wide imaging and analysis, yet their application to clinical formalin-fixed paraffin-embedded (FFPE) blocks remains challenging. We introduce HIF-Clear, a novel method for efficiently clearing and labeling centimeter-thick FFPE specimens using elevated temperature and concentrated detergents. HIF-Clear with multi-round immunolabeling reveals neuron circuitry regulating multiple neurotransmitter systems in a whole FFPE mouse brain and is able to be used as the evaluation of disease treatment efficiency. HIF-Clear also supports expansion microscopy and can be performed on a non-sectioned 15-year-old FFPE specimen, as well as a 3-month formalin-fixed mouse brain. Thus, HIF-Clear represents a feasible approach for researching archived FFPE specimens for future neuroscientific and 3D neuropathological analyses.

Lately, carbazole‐based self‐assembled monolayers (SAMs) are widely employed as effective hole‐selective layers (HSLs) in inverted perovskite solar cells (PSCs). Nevertheless, these SAMs tend to aggregate in solvents due to their amphiphilic nature, hindering the formation of a monolayer on the ITO substrate and impeding effective passivation of deep defects in the perovskites. In this study, a series of new SAMs including DPA‐B‐PY, CBZ‐B‐PY, POZ‐B‐PY, POZ‐PY, POZ‐T‐PY, and POZ‐BT‐PY are synthesized, which are employed as interfacial repairers and coated atop CNph SAM to form a robust CNph SAM@pseudo‐planar monolayer as HSL in efficient inverted PSCs. The CNph SAM@pseudo‐planar monolayer strategy enables a well‐aligned interface with perovskites, synergistically promoting perovskite crystal growth, improving charge extraction/transport, and minimizing nonradiative interfacial recombination loss. As a result, the POZ‐BT‐PY‐modified PSC realizes an impressively enhanced solar efficiency of up to 24.45% together with a fill factor of 82.63%. Furthermore, a wide bandgap PSC achieving over 19% efficiency. Upon treatment with the CNph SAM@pseudo‐planar monolayer, also demonstrates a non‐fullerene organic photovoltaics (OPVs) based on the PM6:BTP‐eC9 blend, which achieves an efficiency of 17.07%. Importantly, these modified PSCs and OPVs all show remarkably improved stability under various testing conditions compared to their control counterparts. [ABSTRACT FROM AUTHOR]

The current bottleneck in the development of efficient photocatalysts for hydrogen evolution is the limited availability of high‐performance acceptor units. Over the past nine years, dibenzo[b,d]thiophene sulfone (DBS) has been the preferred choice for the acceptor unit. Despite extensive exploration of alternative structures as potential replacements for DBS, a superior substitute remains elusive. In this study, a symmetry‐breaking strategy was employed on DBS to develop a novel acceptor unit, BBTT‐1SO. The asymmetric structure of BBTT‐1SO proved beneficial for increasing multiple moment and polarizability. BBTT‐1SO‐containing polymers showed higher efficiencies for hydrogen evolution than their DBS‐containing counterparts by up to 166 %. PBBTT‐1SO exhibited an excellent hydrogen evolution rate (HER) of 222.03 mmol g−1 h−1 and an apparent quantum yield of 27.5 % at 500 nm. Transient spectroscopic studies indicated that the BBTT‐1SO‐based polymers facilitated electron polaron formation, which explains their superior HERs. PBBTT‐1SO also showed 14 % higher HER in natural seawater splitting than that in deionized water splitting. Molecular dynamics simulations highlighted the enhanced water‐PBBTT‐1SO polymer interactions in salt‐containing solutions. This study presents a pioneering example of a substitute acceptor unit for DBS in the construction of high‐performance photocatalysts for hydrogen evolution. [ABSTRACT FROM AUTHOR]

Photocatalytic hydrogen production (PHP) from water is a promising solution for environmental pollution due to its high energy density and the abundant availability of water and solar energy on Earth. 1,1-dicyanomethylene-3-indanone (IC) has been widely used as an end group in organic photovoltaics owing to its strong electron-withdrawing ability and planarity. However, research on the application of IC structures in PHP is limited due to synthesis challenges. In this study, we designed a series of novel IC-based monomers incorporating a dibenzothiophene-S,S-dioxide unit through Suzuki coupling. These monomers were used to synthesize polymers with varying degrees of malononitrile substitution, referred to as ICFTDB, ICTDB, and IDMTDB. We investigated the correlation between the optical, electrochemical, and hydrogen evolution performances of these polymers. Through transient absorption spectroscopy, we demonstrated that ICTDB exhibited enhanced capabilities for ultrafast electron transfer and reduced recombination effects. As a result, ICTDB, photocatalysts with IC-containing structures achieved a hydrogen evolution rate of 30.0 mmol g−1 h−1, which was 11.5 times higher than that of ICFTDB, the polymer with no malononitrile substitution. This study provides valuable insights into the potential of IC-based conjugated polymers for photocatalytic hydrogen evolution. [ABSTRACT FROM AUTHOR]

The exploration of deactivation mechanisms for near‐infrared(NIR)‐emissive organic molecules has been a key issue in chemistry, materials science and molecular biology. In this study, based on transient absorption spectroscopy and transient grating photoluminescence spectroscopy, we demonstrate that the aggregated PtII complex 4H (efficient NIR emitter) exhibits collective out‐of‐plane motions with a frequency of 32 cm−1 (0.96 THz) in the excited states. Importantly, similar THz characteristics were also observed in analogous PtII complexes with prominent NIR emission efficiency. The conservation of THz motions enables excited‐state deactivation to proceed along low‐frequency vibrational coordinates, contributing to the suppression of nonradiative decay and remarkable NIR emission. These novel results highlight the significance of excited‐state vibrations in nonradiative processes, which serve as a benchmark for improving device performance. [ABSTRACT FROM AUTHOR]

We have used aperiodically poled lithium niobate waveguides to perform intensity autocorrelation and frequency-resolved optical gating (FROG) measurements for ultraweak femtosecond pulses at 1.5 [micro]m wavelength. The required pulse energies for intensity autocorrelation and FROG are as low as 52 aJ and 124 aJ, respectively. The corresponding sensitivities are 3.2 x [10.sup.-7] m[W.sup.2] and 2.7 x [10.sup.-6] m[W.sup.2], about 3-5 orders of magnitude better than the previous records. The high nonlinear conversion efficiency is attributed to the long waveguide structure, and the needed broad phase-matching bandwidth is realized by chirping the poling period. We discuss the theory of intensity autocorrelation and FROG measurements in the presence of different phase-matching bandwidths, and we show, for the first time to our knowledge, that the distorted intensity autocorrelation trace due to a b-like phase-matching spectrum is described by a modified field autocorrelation function. We also report new experimental results comparing autocorrelation traces measured with chirped and unchirped waveguide samples and demonstrating high-quality FROG measurements for cubic phase waveforms generated in a programmable pulse shaper. OCIS codes: 320.7100, 190.7110, 130.3730, 120.3180.