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Achieving facile and simple temperature- and pressure-induced transformation of sp2-to-sp3 remains an important and fascinating challenge within the realm of carbon science and technology. Here, we introduce a new technique that utilizes repeated exposure of low-pressure (2.0 MPa) millisecond acoustic shock waves on a sample to facilitate the successful transformation of sp2-to-sp3 carbon bonds. This transformation is verified through visible Raman spectroscopic, X-ray photoelectron spectroscopic (XPS), and high-resolution transmission electron microscopic (HRTEM) observations. Typically, in general nanosecond dynamic compression experiments, sp3 carbon bond formation occurs only at pressures of ∼45 GPa or more, and under static compression, this transition takes place at ∼30 GPa. However, with our innovative approach, similar results can be achieved with acoustic shock waves operating at significantly lower pressures of 2.0 MPa. Based on the observed analytical results, the sp2-to-sp3 type phase transition occurred at the 500-shocked condition and this transition leads to the conversion of layered crystalline graphite to non-layered amorphous graphite, which may be the pre-state of sp3 bonded diamond formation. The complete disappearance of the 2D band in the Raman spectrum and the conversion of asymmetric to symmetric shape of the C 1s band in the XPS spectrum are the major proof for the proposed sp2-to-sp3 phase transition. Further optimization is currently underway to find the critical point in achieving the probable phase transition of graphite to diamond. The proposed technique put forward a platform for a new impending way to make the sp3 carbons from sp2 carbons in indoor laboratories, which may also offer a new science division to understand the formation of diamonds or diamond-like structures under lower transient pressure conditions. Even though the proposed technique is cost-effective and involves a handy tool, to move it from lab to industrial applications, we still have a lot of ground to cover in fundamental aspects. [ABSTRACT FROM AUTHOR]

Glycinium oxalate (GO) and Bis(glycinium) oxalate (BGO) crystals are successfully grown using the slow evaporation solution growth technique. Following their growth, the crystals are subjected to a series of acoustic shock pulses. The effects of these shock pulses on the structural, optical, dielectric, and morphological properties of the crystals are comprehensively analyzed using various characterization techniques, including powder X‐ray diffraction (XRD), UV‐Visible spectroscopy, dielectric spectroscopy, and optical microscopy. Structural analysis through XRD reveals shifts in diffraction peak positions, indicating structural deformations. Fourier transform infrared spectroscopy analysis assesses the chemical stability of GO and BGO under shocked conditions. UV‐Visible spectroscopy shows alterations in optical transmission with successive shock pulses, attributed to structural and surface defects. Dielectric properties are investigated over a frequency range from 1 Hz to 1 MHz, revealing variations in dielectric constant and loss tangent, which provide insights into the electrical behavior of the materials under normal and shocked conditions. Optical and scanning electron microscopy examine surface morphology, visualizing defects induced by the shock pulses. This study highlights the significant impact of shock pulses on the structural properties, optical transmission, dielectric properties, and surface morphology of GO and BGO crystals, offering valuable information on their resilience under dynamic conditions and potential applications. [ABSTRACT FROM AUTHOR]

The development of catalytically dynamic, self-supporting, and cost-effective electrodes equipped with efficient trifunctional catalytic microarchitectures is pivotal in addressing the emerging demands of the healthcare and energy sectors. For the first time, this research reports the strategic integration of three-dimensional Se and P-fused NiSeP (NSP) microflakes with CuFe (CF) composite cubes anchored over an inherently capacious nitrogen-doped carbonized wood (NCW) (NSP-CF@NCW) and explores the impact of diverse strategies of electron and microstructural engineering of electrocatalytic sites on the trifunctional performances for enzyme-free urea sensing and urea electrolysis. Among the array of built electrodes, the NSP-CF@NCW electrode exhibits excellent multifaceted electrocatalysis ability triggered by the synergistic effects of highly voluminous and interconnected NSP flakes anchored over the CF composite, which results in unique electron channeling for efficient electrocatalytic kinetics. The NSP-CF@NCW electrode as a urea sensor exhibits momentous sensitivities of 33.1 and 7.0 mA mM−1 cm−2 accompanied with the corresponding broad linear ranges of 0.01–0.5 mM and 0.5–9.0 mM, respectively, and a detection limit of 0.0085 mM (S/N = 3). Moreover, as a urea electrolyzer, the best-performing electrode requires an overpotential of 1.49 V to deliver a high current density of 50 mA cm−2, which is 210 mV lower than that required for the standard alkaline water splitting reaction. [ABSTRACT FROM AUTHOR]

Amino acids are among the earliest organic molecules to exist on Earth, and the origin of such bio-molecules on Earth is still a topic of intense discussion in the associated scientific area. In this regard, one of the crucial methods to investigate this subject and to better comprehend the emergence of biomolecules on the planet is to carry out indoor laboratory-size shock wave recovery experiments. In this instance, we have investigated the structural and morphological properties of L -serine powder samples processed using acoustic shock waves. The effects of shock waves on the title sample have been studied using conventional diffraction and microscopy methods. According to the diffraction results, under shocked conditions, there has been no crystallographic phase change observed, whereas the entire test samples have undergone dynamic recrystallization with the same P212121 space group. Shock wave-driven dynamic recrystallization theories can explain the observed surface changes on the test samples, which underwent considerable surface modifications under shocked conditions. [ABSTRACT FROM AUTHOR]

We present our findings on the room temperature (RT) soft ferromagnetism (FM) of the sol-gel-prepared Co-doped barium titanate (BaTiO3) nanoparticles with two distinct Co concentrations (0.25 mol% and 0.5 mol%), that is appropriate for spintronic applications as evidenced by experimental observations. X-ray diffraction investigation revealed that the produced samples, which had diameters less than 100 nm, belonged to the pseudo-cubic phase of the BaTiO3 structure and did not exhibit any signs of the Co cluster or any other Co oxides. UV-visible absorption spectra demonstrate that the optical response is red shifted and the bandgap energy is lowered when Co is incorporated into the BaTiO3 lattice. The inclusion of cobalt ions may have brought about a change in size or an increase in surface defects, as evidenced by the PL spectra, which show that the intensity of emission peaks changes as the dopant concentration increases. In the 0.25 mol% Co-doped BaTiO3 sample, the FM behavior is clearly visible along with the paramagnetic (PM) phase at RT. Significantly, it becomes apparent that as the doping concentration is raised to 0.5 mol%, the saturation magnetization is reduced, and a pure phase of soft FM is obtained. This soft FM feature witnessed in 0.5 mol% doped BaTiO3 with low coercivity (96.8 Oe) and low saturation magnetization (9.7 × 10−3 emu/g) is likely due to oxygen vacancies and could set out as a promising magnetic material for possible spintronic applications. [ABSTRACT FROM AUTHOR]

Indium selenide is a semiconducting material that has a layer-by-layer crystal structure. The present work treats indium selenide with dynamic shock waves using a semi-automatic Reddy tube at 100, 200, 300, and 400 shock pulses. The mixed phase of In4Se3 and α-In2Se3 switched to pure rhombohedral (α-In2Se3) at 100 shock pulses and remained in the same phase up to 400 shock pulses due to application of 2.0 MPa pressure and temperature of 864 K. The crystal structure transformation from orthorhombic to rhombohedral was examined using powder X-ray diffraction and Raman scattering analyses, through the formation and disappearance of peaks, the results from XRD and Raman confirm the phase transition. The morphology and optical properties of the material were investigated using scanning electron microscopy and UV-DRS. The morphology of In2Se3 is of layered shape during increasing shocks. Optical analysis revealed that the band gap of the sample increased, changing from a wide to a narrow band gap semiconducting material. [ABSTRACT FROM AUTHOR]