Raman and Brillouin scattering are sensitive approaches to detect chemical composition and mechanical elasticity pathology of cells in cancer development and their medical treatment researches. The application is, however, suffering from the lack of ability to synchronously acquire the scattering signals following three-dimensional (3D) cell morphology with reasonable spatial resolution and signal-to-noise ratio. Herein, we propose a divided-aperture laser differential confocal 3D Geometry-Raman-Brillouin microscopic detection technology, by which reflection, Raman, and Brillouin scattering signals are simultaneously in situ collected in real time with an axial focusing accuracy up to 1 nm, in the height range of 200 μm. The divided aperture improves the anti-noise capability of the system, and the noise influence depth of Raman detection reduces by 35.4%, and the Brillouin extinction ratio increases by 22 dB. A high-precision multichannel microspectroscopic system containing these functions is developed, which is utilized to study gastric cancer tissue. As a result, a 25% reduction of collagen concentration, 42% increase of DNA substances, 17% and 9% decrease in viscosity and elasticity are finely resolved from the 3D mappings. These findings indicate that our system can be a powerful tool to study cancer development new therapies at the sub-cell level.

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Rational design of efficient, sustainable and low-cost hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) bifunctional catalysts within the scope of feasibility is of great significance for realizing rapid output water splitting. Here, we used a simple coprecipitation method to prepare Keggin-type polyoxometalate (POM) nanoscale particles coated with coreshell-type metal-organic framework (MOF) derived Co-NC (Co-NC-POM). Thanks to synergy effect, abundant active sites, unique structure and defects, the as-synthesized Co-NC-POM hybrids exhibit excellent eletrocatalytic performance both for HER and OER. Moreover, it can act as bifunctional electrocatalysts for overall water splitting, exhibiting a low voltage of 1.60 V and an excellently stability up to 24 h at a current density of 10 mA cm À 2 . It shows competitive performance against the same type of advanced bifunctional catalysts currently reported and thus is expected to among the most efficient non-precious metal catalysts to drive the water splitting device.

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Confocal Brillouin microscopy (CBM) is a novel and powerful technique for providing non-contact and direct readout of the micro-mechanical properties of a material, and thus used in a broad range of applications, including biological tissue detection, cell imaging, and material characterization in manufacturing. However, conventional CBMs have not enabled high precision mechanical mapping owing to the limited depth of focus and are subject to system drift during long-term measurements. In this paper, a divided-aperture confocal Brillouin microscopy (DCBM) is proposed to improve the axial focusing capability, stability, and extinction ratio of CBM. We exploit high-sensitivity divided-aperture confocal technology to achieve an unprecedented 100-fold enhancement in the axial focusing sensitivity of the existing CBMs, reaching 5 nm, and to enhance system stability. In addition, the dark-field setup improves the extinction ratio by 20 dB. To the best of our knowledge, our method achieves the first in situ topographic imaging and mechanical mapping of the sample and provides a new approach for Brillouin scattering applications in material characterization.