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Because copper phthalocyanine (CuPc) has significant uses in industrial devices and pigments, it is a subject of great interest in basic scientific research. Studying and adjusting its photoelectric qualities, in particular, has drawn much attention. In this work, in situ high-pressure experiments were used to investigate in detail the vibrational and optical properties of ground-state β-CuPc up to 13 GPa. Both micro-Raman and ultraviolet and visible light (UV–vis) absorption measurements revealed a phase transition occurring around 3 GPa. Notably, the macrocycle breathing vibration was found to have a remarkable characteristic of first weakening and then strengthening in response to this pressure-induced phase transition. The UV–vis absorption data revealed that the bandgaps corresponding to the two absorption edges decrease gradually with increasing pressure, with one edge disappearing entirely above 11 GPa. Furthermore, the blue β-CuPc can be adjusted to dark green at 10 GPa and ultimately entirely black due to the merging of its absorption bands and redshifts at high pressure. This work improves our understanding of CuPc's intrinsic characteristics under harsh settings and manipulates its color effectively. [ABSTRACT FROM AUTHOR]

Photochromic yttrium oxyhydride (YHO) shows a very attractive color-neutral darkening upon photoactivation. However, the exact defect or state responsible for the visible light absorption or the mechanism for its creation is not fully understood. This makes it challenging to optimize and modify the material. In this work, we have investigated the relationship between photon absorption and darkening profile into a YHO film. The extinction coefficient k(λ) is obtained from spectroscopic ellipsometry, and the expected photon absorption profile is calculated. This is then compared to transmittance data during photodarkening by short-wavelength UV (254 nm). Our results show that the darkening is not homogeneous through the film, showing that photon absorption and darkening are positionally correlated, yet we show that the darkening stretches further into the film than the calculated photon absorption. A homogeneously darkened sample cannot always be assumed when assessing optical transmittance, absorbance, and ellipsometry data. [ABSTRACT FROM AUTHOR]

Corn-like ZnO/Ag2S heterojunctions are designed and prepared by the solvothermal method and the subsequent covering process. They construct a type II core–shell heterojunction structure. This structure adjusts the relative positions of electron energy levels and generates a strong and broad absorption band, while emitting weak visible light. It also facilitates the transfer of photoexcited carriers through the interface and the confinement of the same by the different components of the nanostructure. Separation of electrons and holes makes them possible to drift to the surface of ZnO and Ag2S and to participate in the redox reactions. In addition, the presence of many defects produces many active sites on the surface of the lattice. So, the ZnO/Ag2S heterojunctions exhibit excellent photocatalytic properties in the first and second cycles of the photocatalytic process. It degrades 97.7% Rhodamine B only in 18 min. This study plays a significant role in promoting visible light catalysis, the efficiency of wastewater treatment technology, and the water environment on the earth. [ABSTRACT FROM AUTHOR]

We attempted to deposit a platinum (Pt) layer onto a tungsten trioxide (WO3) thin film (Pt/WO3). The Pt layer deposited on WO3 was oxidized by calcining Pt/WO3 in air to form PtOx/WO3. An n-type anomalous photo-thermoelectric (photo-TE) effect was confirmed for Pt/WO3 and Pt/HyWO3−x. HyWO3−x is a protonated WO3 after the gaschromic (GC) reaction of WO3 in Pt/WO3. The anomalous photo-TE effect was that both the electrical conductivity (σphoto) and the absolute value of the Seebeck coefficient (Sphoto) increased under UV light or visible light irradiation. After stopping the irradiation, σphoto and Sphoto decreased. In contrast, an n-type normal photo-TE effect was observed for PtOx/HyWO3−x after the GC reaction of PtOx/WO3, in which σphoto increased and the absolute value of Sphoto decreased under ultraviolet (UV) light irradiation, and vice versa after stopping the irradiation. These findings indicate that Pt was responsible for the anomalous photo-TE effect due to the electron accumulation capability of Pt, to which electrons were transferred from the conduction band of HyWO3−x. In contrast, electrons could not energetically transfer from HyWO3−x to PtO2, which existed in PtOx particles at the surface. Therefore, PtOx/HyWO3−x behaved similar to sole HyWO3−x, indicating the normal photo-TE effect. [ABSTRACT FROM AUTHOR]

β-LiGaO2 with a wurtzite-like crystal structure is a direct ultra-wide bandgap semiconductor. Similar to many wide bandgap oxides, the valence band of LiGaO2 is predominantly composed of O-2p orbital, leading to a low valence band position, drastically limiting its applications. In this work, we employ first-principles calculations to demonstrate that adding a small amount of Bi into LiGaO2 to form the highly mismatched Li(Ga1−xBix)O2 alloys can dramatically modulate the valence band compositions. Compared to LiGaO2, the valence band maximum of the alloys is significantly elevated, and a fully occupied intermediate valence band appears, further raising the valence band positions. Despite the appearance of intermediate valence bands that significantly reduce the alloys' bandgap, the bandgap remains over 3.10 eV, ensuring visible light transparency. With increasing Bi composition in the alloys, the bulk modulus increases while the shear modulus gradually decreases, which improves the ductility. Moreover, the compliant elastic constants of the alloys indicate mechanical stability. These findings suggest that Li(Ga1−xBix)O2 alloys are promising flexible transparent conductive oxides, offering valuable insights for future applications. [ABSTRACT FROM AUTHOR]

This study investigates the impact of biaxial strain on monolayer black phosphorus (BP) through first-principles calculations, confirming its stability and subsequently modifying its photocatalytic performance. Under biaxial strain, BP exhibits a direct bandgap suitable for photocatalytic hydrogen production during water splitting, albeit with limitations due to its valence band maximum edge. A distinctive GaN/BP heterojunction is proposed, featuring a direct bandgap and advantageous band edge positions conducive to efficient photocatalytic overall water splitting. Under the influence of biaxial strain, the heterojunction type undergoes a transition from direct type-I to direct type-II and Z, augmenting the separation of photoexcited electrons and holes and markedly enhancing the efficiency of photocatalytic hydrogen production. Furthermore, the heterojunction exhibits commendable capabilities in absorbing visible light. This research provides a promising avenue to surmount the constraints associated with monolayer BP in photocatalysis, offering valuable insights for the development of efficient photocatalytic materials. [ABSTRACT FROM AUTHOR]

Amorphous carbon nitride (a-CNx) films, prepared by reactive radio frequency magnetron sputtering, exhibit unique characteristics under visible light irradiation, referred to as photoinduced deformation. This phenomenon represents an energy conversion system wherein photon energy transforms into kinetic energy. The chemical bonding structure of a-CNx films was analyzed using near-edge x-ray absorption fine structure (NEXAFS) at the NewSUBARU synchrotron facility of the University of Hyogo, Japan. This analysis aimed to elucidate the mechanisms behind the photoinduced deformation observed in a-CNx films. Three variants of a-CNx films, displaying varying degrees of photoinduced deformation, were deposited using a graphite target and nitrogen gas under different deposition temperatures. The NEXAFS spectra of the a-CNx films with substantial photoinduced deformation showed changes under light irradiation from a Xe lamp (directed through an optical window within the NEXAFS chamber). Specifically, the peaks corresponding to the 1s to π* transition related to C—C and 1s to σ* transition related to C—N bonds exhibited high sensitivity to visible light irradiation. Simultaneously, the N K-edge spectra associated with the 1s to π* transition, attributed to the N—C bond, exhibited a slight intensity decrease. Conversely, the C K-edge spectrum in the a-CNx films displaying minimal photoinduced deformation remained unchanged under visible light irradiation. The N K-edge spectra maintained a consistent shape under both visible light and dark conditions. [ABSTRACT FROM AUTHOR]

In 3D-deposited AgNW/TiO2, which is prepared by spray-applying titanium dioxide suspension to deposited silver nanowire sheets, the synergistic effects of increased crossing points of AgNWs to enhance localized surface plasmon resonance excitation and longer-lived electrons in the conduction band of TiO2 generated by plasmon-induced charge transfer have successfully resulted in photocatalytic activity in the visible light range. We have developed photocatalytic sheets in which TiO2 particles are uniformly attached to 3D-deposited AgNWs. Regarding the prepared sheet, it was confirmed that TiO2 was indeed well adhered to the AgNWs, and electron transfer was efficient at the interface. This sheet solves the problem that the response wavelength range of the photocatalytic reaction using TiO2 is only in the ultraviolet region and exhibits sufficient photocatalytic effect in the visible light region. Transient absorption spectroscopy measurements in the diffuse reflectance configuration confirmed that the electrons of AgNWs actually move into the conduction band of TiO2 under visible light and that the interaction is independent of the excitation light intensity, thereby extending the lifetime of the electrons. [ABSTRACT FROM AUTHOR]

In this study, we used the non-hydrolytic sol–gel methodology to synthesize gadolinium vanadate particles doped with different Er3+ and Yb3+ molar ratios. Er3+ and Yb3+ chlorides and vanadium alkoxide were used as precursors during the sol–gel synthesis. The resulting powders were treated at 800 °C and characterized by x-ray diffraction and photoluminescence. The x-ray diffractogram displayed peaks attributed to the gadolinium vanadate matrix. Photoluminescence helped to evaluate the Fluorescence Intensity Ratio (FIR), which is important for understanding the nanothermometer property. The FIR of the GdVO4:Er3+/Yb3+ samples containing different Er3+ and Yb3+ molar ratios increased as a function of the laser power, which indicated that the local temperature increased. The excitation spectra obtained at fixed wavelengths of 525 and 555 nm displayed bands at 322, 379, and 489 nm, ascribed to the charge transfer band and Er3+ levels. Upon excitation at 321 nm, the emission spectra in the visible region presented intense bands at 525 and 555 nm, due to Er3+ emission, and excitation at 321 nm led to emission in the infrared region, 980 and 1550 nm. In conclusion, the synthesized system can be employed as a temperature sensor. [ABSTRACT FROM AUTHOR]

The precise detection of target substances through refractive-index sensing is essential in various fields such as environmental monitoring, food assessment, and optical applications. This study demonstrates a real-time refractive index sensor based on a liquid-infiltrated metal-insulator-metal island (MIMi) structure in a lithography-free manner. In the MIMi structure, the top layer of the metal islands is formed through solid-state dewetting, which serves as an etching mask to form nanopillars in the insulator layer. This allows for the infiltration of external substances, resulting in different structural colors depending on the refractive index. This design results in a redshift of the resonance peak as the infiltrated refractive index increases. Furthermore, by adjusting the area fraction of the metal-island layer and etching depth of the insulator layer, the resonance-peak position can be controlled within the visible range according to the target refractive index. The advantages of our design are the use of cost-effective materials and the ability to implement scalable fabrication. Our proposed method offers a convenient method to sense the target refractive index in real time. [ABSTRACT FROM AUTHOR]

Antiferromagnetic materials have recently been proposed as new types of terahertz (THz) range spintronic devices owing to their ultrafast spin dynamics. Manipulating their spin dynamics expediently, however, remains a key challenge. Here, we demonstrate the laser excitation of magnons in a prototypical antiferromagnet NiO via spin–phonon coupling. The terahertz time-domain spectrum revealed the frequencies of antiferromagnetic magnons near 1 THz. Laser excitations in the visible spectrum caused a noticeable softening of the magnons. Raman spectroscopy results established the presence of optical phonons. The laser heating effect was excluded by finite-element analysis and variable-temperature measurements. The temperature- and power-dependent properties suggest an optical phonon–magnon coupling mechanism. Laser excitation raises the optical phonon temperature, linked with the magnon temperature, via the magnon–phonon interaction. Consequently, the magnon temperature rises, and the magnon mode frequency softens. Our findings shed light on spin–phonon coupling in antiferromagnetic insulators and open a route for creating rapid opto-spintronic devices that utilize antiferromagnetic materials. [ABSTRACT FROM AUTHOR]

The immobilization of Re(I) complexes onto metal oxide surfaces presents an elegant strategy to enhance their stability and reusability toward photocatalytic CO2 reduction. In this study, the photocatalytic performance of fac-[ClRe(CO)3(dcbH2)], where dcbH2 = 4,4′-dicarboxylic acid-2,2′-bipyridine, anchored onto the surface of 1%m/m CuO/Nb2O5 was investigated. Following adsorption, the turnover number for CO production (TONCO) in DMF/TEOA increased significantly, from ten in solution to 370 under visible light irradiation, surpassing the TONCO observed for the complex onto pristine Nb2O5 or CuO surfaces. The CuO/Nb2O5 heterostructure allows for efficient electron injection by the Re(I) center, promoting efficient charge separation. At same time CuO clusters introduce a new absorption band above 550 nm that contributes for the photoreduction of the reaction intermediates, leading to a more efficient CO evolution and minimization of side reactions. [ABSTRACT FROM AUTHOR]

Quantum technologies utilize photons in a wide range of spectra, from microwave to visible light. Interactions between photons at different frequencies can be mediated by the collective excitation of spins in a ferromagnetic material. Here, we present optic-to-microwave conversions using the spin mode. In the conversion system, we observe that the generation of microwaves can be controlled by the polarization of the infrared input. Furthermore, we miniaturize the system and demonstrate conversion in a cryogenic environment, where microwave photons can be manipulated in the quantum regime. We show that the conversion efficiency scales with the intensity of the infrared illumination. [ABSTRACT FROM AUTHOR]

Semiconductor-based photocatalysts have become increasingly used in the removal of pollutants from wastewater, especially antibiotics. A series of composite-based cuprous oxide and bismuth vanadate (Cu2O/BiVO4) composite-based photocatalysts were synthesized by using the chemical method. The structure of the Cu2O/BiVO4 composite was verified by using x-ray diffraction, scanning electron microscopy, photoluminescence, Fourier transform infrared spectroscopy, and UV–visible spectra. The degradation of methylene blue (MB) and tetracycline (TC) was investigated to check the photocatalytic activity of the Cu2O/BiVO4 composite series. The quantity of Cu2O was varied from 1% to 7% by weight to prepare the series of Cu2O/BiVO4 composites. The analysis of results verified that 5% Cu2O/BiVO4 exhibits an outstanding photocatalytic activity as compared to 1%, 3%, and 7% Cu2O/BiVO4, pure Cu2O, and pure BiVO4 under visible light irradiation. The optimum value of photocatalytic degradation achieved with 5% Cu2O/BiVO4 was 97% for MB dye and 95% for TC in 120 min, which is greater than the photocatalytic degradation of pure BiVO4 (MB 45% and TC 72%), pure Cu2O (MB 57% and TC 80%), 1% Cu2O/BiVO4 (MB 72% and TC 85%), 3% Cu2O/BiVO4 (MB 83% and TC 88%), and 7% Cu2O/BiVO4 (MB 87% and TC 91%). The stability and reusability of Cu2O/BiVO4 were also investigated. To check the major role of trapping in degradation, a trapping experiment was also performed by using three trapping agents: BQ, EDTA, and tBuOH. The results showed that Cu2O/BiVO4 exhibits an improved photocatalytic activity in the degradation of antibiotics in polluted water because the recombination rate of the electron–hole pair decreased and the surface area increased, which increased the active sites for redox reactions. Such a photocatalytic composite with high efficiency has various applications, such as energy production, environmental remediation, and water remediation. [ABSTRACT FROM AUTHOR]

Oblique shock wave–interface interactions of gases and liquids have been extensively studied in shock tubes using optical methods to measure equation-of-state (EOS) parameters. However, this is difficult with solids due to their opaqueness to visible light. X ray phase contrast imaging (XPCI) has the penetrative strength to probe solids while still being sensitive to mass density and enhancing the visibility of material boundaries. We investigate the accuracy and repeatability of measuring the mean value of the average mass density (areal density divided by thickness) over region S (B S) and flow deflection angle (θ) from XPCI images of a sample. To that end, a Hough transform-based method for measuring θ is developed. To measure B S , the XPCI image intensity probability density function (PDF) is modeled accounting for the spatial distribution of x ray energy, scintillator response, and pulse-to-pulse variation in the x ray intensity. In addition, a Monte Carlo-based algorithm for computing the B S PDF is developed. Both methods are validated on an impact-generated oblique shock wave interacting at a solid polymer-to-polymer interface. This is accomplished through a comparison to hydrodynamic simulations using well-established EOS. Under the modeling framework for the XPCI image intensity, B S is computed with an accuracy of < 0.1 % and precision of 3%–5%, while θ has an uncertainty of 0.2 ° , respectively. This shows that the XPCI-based model that is developed here could be an invaluable tool for high-fidelity testing of hydrodynamic models in shock polar configurations. [ABSTRACT FROM AUTHOR]

Indium tin oxide (ITO) film, which is the most commonly used transparent conductive film (TCF), has traditionally been believed to be transparent in the visible spectrum but to reflect infrared (IR) light beyond the plasma wavelength (λp). However, our theoretical analysis challenges this notion by demonstrating that an ultrathin ITO TCF that is thinner than the light's penetration depth can overcome the transmission barrier at λp. To validate the theoretical modeling, we have successfully fabricated ultrathin ITO films that, despite having λp ≈ 1 μm, remain transparent from 400 nm to 20 μm. This represents the broadest transparency range ever reported for any In2O3-based TCF. The 10-nm-thick ITO TCFs have high visible transmittance (91.0% at 550 nm), low resistivity (5 × 10−4 Ω cm), and good IR transmittance (averaging 60% over 1.35–18.35 μm). Their IR transparency facilitates radiative cooling of the underlying circuitry. When an operational resistor is enclosed by commercial ITO TCFs that are 140 nm thick, its temperature increases. However, using 10-nm-thick ITO TCFs instead of the commercial ones can completely avoid this temperature rise. Moreover, attaching a silver grid to a 10-nm-thick ITO TCF can reduce the effective sheet resistance to ∼10 Ω/□ at the expense of only ∼3% transmittance. This development paves the way for large-scale applications that require low sheet resistance and far-IR transparency. [ABSTRACT FROM AUTHOR]

In hyperpolarization experiments using parahydrogen, a partially negative line (PNL) of o-H2 is occasionally spotted in the nuclear magnetic resonance (NMR) spectra. This is a manifestation of the two-spin order (TSO) of the proton spins, appearing transiently in o-H2 molecules freshly derived from p-H2. For the TSO to be observable, the o-H2 NMR signal must be split into a doublet. In the literature, the splitting is believed to originate from a slow exchange of the dissolved dihydrogen with the dihydride moiety bound to a catalyst present in the reaction mixture. Because this hypothesis may be debatable, in this work a different splitting mechanism is proposed. It employs a residual dipolar coupling (RDC) between the hydrogen protons, originating from a partial orientation of the H2 molecules by the external magnetic field. The orientation effect is due to the anisotropic magnetic polarizability of H2. In a magnetic field of 11.74 T at room temperature, the currently predicted value of the RDC is −0.0024 Hz. Even such small RDC values are sufficient for the PNL effect to be clearly visible in NMR spectra for physically reasonable levels of the TSO in the o-H2 molecules. For RDC values much smaller than the natural linewidth of o-H2, the theoretical frequency distance between the minimum and maximum of PNL proves to be practically independent of the RDC and is of the order of the linewidth. The calculated amplitudes of the PNLs are proportional to the RDC values used in the calculations. [ABSTRACT FROM AUTHOR]

Optoelectronic memristors hold the most potential for realizing next-generation neuromorphic computation; however, memristive devices that can integrate excellent resistive switching and both electrical-/light-induced bio-synaptic behaviors are still challenging to develop. In this study, an artificial optoelectronic synapse is proposed and realized using a kesterite-based memristor with Cu2ZnSn(S,Se)4 (CZTSSe) as the switching material and Mo/Ag as the back/top electrode. Benefiting from unique electrical features and a bi-layered structure of CZTSSe, the memristor exhibits highly stable nonvolatile resistive switching with excellent spatial uniformity, concentrated Set/Reset voltage distribution (variation <0.08/0.02 V), high On/Off ratio (>104), and long retention time (>104 s). A possible mechanism of the switching behavior in such a device is proposed. Furthermore, these memristors successfully achieve essential bio-synaptic functions under both electrical and various visible light (470–655 nm) stimulations, including electrical-induced excitatory postsynaptic current, paired pulse facilitation, long-term potentiation, long-term depression, spike-timing-dependent plasticity, as well as light-stimulated short-/long-term plasticity and learning-forgetting-relearning process. As such, the proposed neotype kesterite-based memristor demonstrates significant potential in facilitating artificial optoelectronic synapses and enabling neuromorphic computation. [ABSTRACT FROM AUTHOR]

Alpha-fetoprotein (AFP) is a characteristic marker of liver cancer, and its accurate detection is of great significance for the early detection of liver cancer. This study utilizes visible light as the excitation light source, employs electrochemical measurement, and incorporates the AFP aptamer as the biorecognition element to construct a photoelectrochemical (PEC) biosensor for the highly sensitive detection of AFP. A Z-scheme heterostructure is constructed via a two-step hydrothermal method, and CdS nanoparticles are anchored on TiO2NRA and BiOI nanosheets with high specific surface areas. The photocurrent response of the BiOI/CdS/TiO2NRA composite material is 4.5 times that of TiO2NRA. By analyzing the energy band positions, the electron transfer mechanisms of Z-scheme heterojunctions in CdS/TiO2NRA and BiOI/CdS photoactive materials were elucidated. Subsequently, the AFP aptamer was immobilized on the base electrode surface via the C＝N structure to fabricate a self-supporting sensing platform. The PEC biosensor demonstrates excellent detection performance within the linear range of 1 nM ∼ 250 nM, exhibiting high selectivity and the detection limit is 0.59 nM (S/N = 3). It has been effectively utilized for the detection of AFP in blood, providing a practical method for early detection and prevention of liver cancer, and also offering new insights for the design of other similar characteristic marker biosensors. [ABSTRACT FROM AUTHOR]

The construction of semiconductor van der Waals (vdW) heterostructures has emerged as a promising approach to enhance the performance of photocatalysts for water splitting. In this study, a PtS2/HfGe2N4 vdW heterojunction was designed, and its photocatalytic properties were investigated using first-principles calculations. The results indicate that the heterojunction exhibits strong light absorption and features a type-II band alignment. Charge transfer within the heterojunction creates an internal electric field, enabling its action as a direct Z-scheme photocatalyst. Additionally, its well-suited band edge position facilitates the redox reactions required for water splitting. Notably, the heterojunction demonstrates a high-intensity light absorption coefficient of 3.8 × 105 cm−1 at 2.3 eV corresponding to the green light in the visible spectrum, highlighting the heterojunction's potential for photocatalytic water splitting applications. [ABSTRACT FROM AUTHOR]

Crystals of trans-3,3′-dimethylazobenzene (DMAB) exhibit crawling motion on solid surface upon simultaneous exposure to ultraviolet (UV) and visible light from opposite directions. In this study, the shape and velocity during the photoinduced crawling motion of DMAB crystals are successfully controlled by irradiation light intensities. A higher intensity of the visible light than the UV light causes the crystals to be spread shape and move slower (∼1 μm min−1). In contrast, a stronger UV light allows them to be droplet-like shape and move faster (∼4 μm min−1). The shape and velocity can be varied by adjusting the light intensities. Shape transformation is effectively applied to cargo capture–carry–release tasks. In particular, spread-shaped crystals capture silica particles over a wide area, whereas droplet-like crystals gather and transport them. This result suggests that a multifunctional soft transporter composed of a single component does not require complex fabrication, thereby contributing to the fields of soft robotics and microfluidics. [ABSTRACT FROM AUTHOR]

Carbon nitride is a promising photocatalyst for hydrogen peroxide (H2O2) production under visible light irradiation. However, current carbon nitride-based photocatalysts show limited H2O2 production owing to high impedance and poor charge transfer ability. In this work, we present a series of CuO decorated graphitic phase carbon nitride (g-C3N4) composites, exhibiting suitable bandgaps for the photocatalytic production of H2O2. The experimental results showed that CuO/g-C3N4 composites exhibited excellent photocatalytic H2O2 production performance and good photocatalytic cycle stability. Significantly, the optimized 30%-CuO/g-C3N4 composite exhibits a high H2O2 yield of 2722.47 μmol L−1 with the addition of CH3OH under visible light. Furthermore, the photocatalytic mechanism is well studied by density functional theory calculations. This work demonstrates that CuO/g-C3N4 composites hold great promise for photocatalytic H2O2 production application. [ABSTRACT FROM AUTHOR]

The application scope of various bioconjugation technologies has been expanded through the implementation of photoredox catalytic bioconjugation technology, establishing a novel biomolecular framework with exceptional residue selectivity. Herein, we report a facile acylation reaction utilizing a thioacid and a photoexcited riboflavin tetraacetate (RFTA) catalyst under visible light (450 nm). The optimal reaction conditions were obtained using a high-throughput microfluidic-based chemical robotic system and GPR model. We have successfully modified a range of proteins and antibodies and utilized the functional handle to attach diverse biological molecules, demonstrating the versatility and generality of our approach. In addition, this photoredox catalytic reaction was also successfully employed in peptide modification, protein labeling, and antibody conjugation. [ABSTRACT FROM AUTHOR]

The degradation of organic dyes under visible light is an effective method to reduce environmental pollution. The key to implementing this method is to develop good photocatalysts. Under hydrothermal conditions, four polyoxometalate-based compounds were prepared, namely, [Co2(TPTP)4(H2O)4(SiMo12O40)]·4H2O (1), [Ni2(TPTP)4(H2O)4(SiMo12O40)]·2.5H2O (2), {[Cu(H2TPTP)(TPTP)(H2O)3]2(SiMo12O40)2}·7.5H2O (3), and {Cu2(TPTP)2(β-Mo8O26)1/2}·H2O (4) (TPTP = 4-[2-(5-pyridyl-4-yl-1,2,4-triazol-1-yl)-methyl]-pyran). Compounds 1 and 2 are isostructural, showing a two dimensional (2D) metal–organic layer. The Keggin anions are discrete between adjacent layers. Compound 3 contains a bi-supporting Keggin anion and a discrete anion. The TPTP ligands in 4 were linked by Cu atoms to form ladder like chains, which are connected by β-Mo8O264− anions to construct a 2D layer. The compounds can be used as photocatalysts. They have good separation efficiency of photogenerated electron–hole pairs. When compounds 1 and 2 were used as photoelectrocatalysts, they exhibited good photoelectrocatalytic activities. The compounds also exhibit excellent electrochemical performance and can be used as electrochemical sensors for the selective recognition of NO2− and Cr(VI). [ABSTRACT FROM AUTHOR]

The synthesis of novel polyoxovanadates (POVs) has received considerable critical attention. Herein, two new POVs, {V12P8} (1) and {V16P8} (2), have been designed and synthesized based on phenylphosphonic acid (PhPO3H2) under solvothermal conditions. The structure of 2 is a 16-nuclearity POV composed of four rare zigzag {V4} secondary building units (SBUs). To the best of our knowledge, 2 is the first POV synthesized with PhPO3H2 including this zigzag SBU, which is also very rare among all POVs. Moreover, 2 is the highest-nuclearity isopolyoxovanadate (IPOV) synthesized using PhPO3H2 as the only organic ligand so far. The photocatalytic properties of 1 and 2 were studied under visible light. Both 1 and 2 demonstrate good performance in photocatalytic oxidation of 1,5-dihydroxynaphthalene (1,5-DHN). Compound 1 also has a photocatalytic effect on MB degradation, with 87% of MB degradation within 8 minutes. [ABSTRACT FROM AUTHOR]

Gold nanoclusters (Au NCs) exhibit broad fluorescent spectra from visible to near-infrared regions and good enzyme-mimicking catalytic activities. Combined with excellent stability and exceptional biocompatibility, the Au NCs have been widely exploited in biomedicine such as biocatalysis and bioimaging. Especially, the long fluorescence lifetime and large Stokes shift attribute Au NCs to good probes for fluorescence sensing and biological detection. In this review, we systematically summarized the molecular structure and fluorescence properties of Au NCs and highlighted the advances in fluorescence sensing and biological detection. The Au NCs display high sensitivity and specificity in detecting iodine ions, metal ions, and reactive oxygen species, as well as certain diseases based on the fluorescence activities of Au NCs. We also proposed several points to improve the practicability and accelerate the clinical translation of the Au NCs. [ABSTRACT FROM AUTHOR]

Photocatalysts for hydrogen evolution reaction (HER) have widely been explored but fine-tuning and engineering multiphase photocatalyst components are still challenging. Among catalysts, ZnIn 2 S 4 has shown promise but maximizing the use of ZnIn 2 S 4 -photogenerated carriers and enhancing quantum yield still require further investigation. One way to achieve this is by enhancing the photon utilization and reducing the recombination of shallow carriers in ZnIn 2 S 4. Accordingly, novel ZnIn 2 S 4 /g-C 3 N 4 /MoS 2 type-II heterojunction composites with 2D/2D/2D structures (abbreviated ZIS/CN/MS) were synthesized in the present work by simple thermal condensation-solvothermal method. The optimized ZIS/CN/MS exhibited a photocatalytic hydrogen evolution rate of 13.6 mmol g−1 h−1 under visible light (λ ≥ 420 nm) irradiation, a value much higher than those of pure-phases ZIS and CN, as well as the binary composite of ZIS/CN. The apparent quantum efficiency of the optimized ZIS/CN/MS at a wavelength of 420 nm reached 27.0 % coupled with excellent cycling stability. The significantly improved photocatalytic performance and the excellent stability can mainly be attributed to the unique 2D/2D/2D arrangement of the ternary components of ZIS, CN, and MS in ZIS/CN/MS photocatalyst, providing a large number of close interfacial contacts between the components for shortened migration distance of photogenerated charges and more pathways for electron separation and transport in type-II heterostructures. Overall, the proposed methodology and ZIS/CN/MS composites with type-II heterojunction and 2D/2D/2D structures have great potential for use in solar-to-hydrogen energy conversion and can be extended to the preparation of other photocatalysts. [Display omitted] • 2D/2D/2D ZnIn 2 S 4 /g-C 3 N 4 /MoS 2 hybrid junction enhances dielectric properties. • New structure provides close interfacial contact and pathway for electron separation. • Unique 2D/2D/2D arrangement improves photocatalytic performance and stability. [ABSTRACT FROM AUTHOR]

This work describes the synthesis, characterization, and photocatalytic evaluation of a polypyrrole-reinforced zinc-nickel mixed metal ferrite (PPy@ Zn 0.5 Ni 0.5 Fe 2 O 4) nanohybrid. A facile hydrothermal process is employed to synthesize the nanostructured zinc-nickel mixed metal ferrite (ZNF), and in situ oxidative polymerization is utilized to create the PPy nanohybrid. In this nanohybrid, PPy plays multiple roles: preventing charge recombination, reducing photocorrosion, mitigating particle aggregation in ZNF, and enhancing charge transfer and visible light absorption. The combined electron-capturing ability, intrinsic conductivity, and extensive π-conjugation of PPy, along with the magnetic nature of ZNF, render the PPy@ZNF catalyst highly efficient. The results of photoluminescence, impedance, and UV/Vis analysis confirm that PPy plays a critical role in enhancing photocatalytic performance by facilitating charge transfer and extending visible-light absorption. In practical environmental applications, the PPy@ZNF nanohybrid demonstrated superior photocatalytic activity compared to ZNF alone, degrading 98.5 % of malachite green dye under W-lamp light within 80 min, with a rate constant of 0.031 min−1. Scavenger and cyclic experiments identified the active species involved in dye degradation and assessed the reusability of the nanohybrid. Extensive testing revealed the optimal conditions for photocatalytic efficiency; the considered variables included light intensity, catalyst dose, dye concentration, temperature, irradiation time, and pH. These findings suggest that the PPy-reinforced ZNF nanohybrid offers cost-effectiveness, magnetic recoverability, structural stability, and high efficacy as a visible light-driven catalyst, making it a promising candidate for diverse environmental remediation applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Caesium tungsten bronze materials are widely used in various applications, such as architectural glass, medicine, insulation coating and textile fibre, owing to their excellent mechanical, optical and thermal properties. In this study, a caesium tungsten bronze (Cs x WO 3 , x = 0.3–0.32) target with a relative density of 99.63 % and uniform microstructure was successfully prepared via hot-pressing sintering. Cs x WO 3 films were deposited on a quartz glass substrate via magnetron sputtering, and the mechanisms and effects of the substrate temperature and oxygen flow rate on the phase structure, microstructure and optical properties of Cs x WO 3 films were investigated. When the substrate temperature increased, the crystallinity and oxygen vacancy concentration of the Cs x WO 3 film improved. Consequently, the visible light transmittance of the film decreased, whereas the infrared blocking rate considerably increased, reaching up to 93.877 %. With the increase in the oxygen flow rate, the visible light transmittance exhibited an increasing trend, reaching a maximum value of 84.319 %, whereas the infrared blocking rate remained relatively stable. We successfully fabricated Cs x WO 3 films possessing a visible light transmittance of 66 % and infrared blocking rate of 94.97 % under the conditions of a substrate temperature of 300 °C and an oxygen flow rate of 2.5 sccm. Our study offers a method for the large-scale production of Cs x WO 3 films, which are excellent infrared shielding materials, rendering a substantial contribution to global energy conservation and emission reduction. [ABSTRACT FROM AUTHOR]

Heterostructured photocatalysts represent an essential role in the catalytic redox reactions in wastewater during illumination. In this contribution, p-n heterojunction PdO/CeO 2 photocatalysts were constructed with enhanced photocatalytic ability for the reduction of Hg(II) utilizing HCOOH as hole scavengers under visible light. PdO NPs were uniformly spread on the mesoporous CeO 2 surface, to act as potential separation centers of electrons and holes. The synthesized PdO/CeO 2 nanocomposites exhibited an excellent photocatalytic ability, contrasted to the bare CeO 2 NPs. The photocatalytic ability of PdO/CeO 2 nanocomposites for reduction of Hg(II) has existed in the trends of 2%PdO ≥1.5%PdO >1%PdO >0.5 % PdO/CeO 2 nanocomposites > bare CeO 2 NPs. A photocatalytic ability of 100 % for Hg(II) reduction was achieved within 40 min utilizing 1.5 % PdO/CeO 2 nanocomposites, which was 2.2 folds greater than that of bare CeO 2 NPs. The rate constant of 1.5 % PdO/CeO 2 nanocomposite (0.106 min−1) is more 9.9 times than that CeO 2 NPs (0.0107 min−1). The enhancement photocatalytic ability of PdO/CeO 2 can be interpreted to the wide surface area, narrow bandgap, numerous active sites, fast mobility, efficient diffusion of Hg(II), and the high separation rate of photocarriers. Considering the promotion photocatalytic ability of heterojunction PdO/CeO 2 nanocomposites, the heterostructure photocatalyst is of magnificent importance to the photocatalytic redox reactions and exhibits a significant effect on our human health and ecological environment. [ABSTRACT FROM AUTHOR]

This study examines the effect of TiO₂ doping on the catalytic performance of copper ferrite (CuFe₂O₄) nanoparticles in degrading methyl green dye under visible light. Copper ferrite nanoparticles were synthesized and doped with varying TiO₂ concentrations. The catalysts were characterized using XRD, SEM, EDX, and BET surface area analysis. The TiO₂-doped copper ferrite catalysts showed significantly enhanced catalytic activity compared to undoped copper ferrite. The optimal doping concentration of 10 wt% TiO₂ achieved a degradation efficiency of 92 % for methyl green dye after 60 min of irradiation. The BET surface area increased with TiO₂ doping, contributing to the improved catalytic performance. Reusability tests over five cycles indicated a slight decrease in efficiency, attributed to the loss of active sites. These results indicate that TiO₂ doping effectively enhances the catalytic properties of copper ferrite, making it a viable option for environmental remediation. [ABSTRACT FROM AUTHOR]

Among different pollutants, organic dyes, phenolic compounds, and antibiotics are three types of hazardous contaminants that have become serious environmental issues. This work deals with the synthesis of new visible-light responsive CsM 0.25 W 1.75 O 6 (M = Ni, Co, Mn, Cu) compounds with a solid-state reaction induced defect pyrochlore structure followed by crushing in a ball mill. The prepared materials were characterized using scanning electron microscopy, X-ray diffraction with Rietveld refinement, X-ray photo-electron spectroscopy, differential thermal analysis, and nitrogen adsorption-desorption measurements at low-temperature. The optimized CsNi 0.25 W 1.75 O 6 (CsNiWO-2) compound was tested for its photocatalytic abatement efficient for several contaminants including methylene blue, phenol, as well as levofloxacin and isoniazid antibiotics. The influence of the various key aspects, such as photocatalyst dosage and hydrogen peroxide concentration, on the degradation efficiency of CsNiWO-2 was examined. The degradation efficiency of CsNiWO-2 (0.6 g L−1) towards methylene blue, phenol, levofloxacin, and isoniazid in the presence of H 2 O 2 (0.06 mol L−1) was 81.4, 47.9, 84.6, and 37.4 %, respectively. Thus, the developed material demonstrates promising properties to degrade methylene blue and levofloxacin. Also, the mechanism and comprehensive schemes for the photooxidation of methylene blue and levofloxacin were elucidated over CsNiWO-2. The present research potentially contributes to designing efficient defect pyrochlores for wastewater treatment under visible light irradiation. [Display omitted] • CsM 0.25 W 1.75 O 6 (M = Ni, Co, Mn, Cu) materials were prepared by a solid-state method. • First report of CsM 0.25 W 1.75 O 6 (M = Ni, Co, Mn, Cu) photodegradation activity. • Grinded CsNi 0.25 W 1.75 O 6 displayed highest activity in the degradation of MB and LFX. • Potential of CsNi 0.25 W 1.75 O 6 photocatalyst for wastewater treatment under LED light. [ABSTRACT FROM AUTHOR]

Photocatalytic technology is considered to be a sustainable strategy to convert H2 O and O2 into H2 O2. However, constructing photocatalytically active and stable organic photocatalyst remain a challenge. In this study, a new class of porous aromatic framework photocatalysts (BF-PAFs) were designed and synthesized, in which 9,9′-bifluorenylidene (99′-BF) and different alkynes are alternately connected. The BF-PAFs were constructed and served as photocatalysts for H2 O2 synthesis. Experimental results show that the introduction of different alkynes can effectively regulate the optical band gap and energy band structure, which may further determine their photocatalytic performance. Upon visible light irradiation, PAF-370 exhibits high efficiency for photosynthesis of H2 O2 with a production rate of 730 μmol g–1 h–1 in the presence of sacrificial reagent from water and oxygen via oxygen reduction reaction (ORR) pathway. Furthermore, up to 61 μmol H2 O2 could be generated from this photocatalytic system after 14 hours. [ABSTRACT FROM AUTHOR]

To achieve dye-sensitized solar cells (DSSCs) with high transparency, multi-color capability, and long-term durability for future applications across various fields, this study selected phenylthiophene with UV-absorbing properties as the dye electron donor, cyanoacetic acid as the electron acceptor, and a colorless biphenyl dye (6OBA) as the co-sensitizer. The effects of different alkyl chain lengths, densities, branching positions, and co-sensitization on the photovoltaic (PV) performance of the devices are investigated. In addition, the effect of dye molecules adsorbed on TiO2 films of different thicknesses on the optical transmittance of the devices was also analyzed. The results show that the developed dyes exhibit UV-selective absorption properties. The power conversion efficiencies (PCEs) of the semi-transparent DSSCs ranged from 0.51% to 0.89% under one sun illumination (100 mW cm−2) and from 3.78% to 5.94% under UVA LED illumination (365 nm, 150 μW cm−2). The corresponding visible light transmittance varied between 33.47% and 63.71%. At the same time, the DSSCs demonstrated long-term PCE stability after soaking for 1000 hours of full light irradiation. [ABSTRACT FROM AUTHOR]

In this study, nanocomposites of g‐C3N4/MN4 (where M is Mn, Fe and Co) have been designed using advanced density functional theory (DFT) calculations. A comprehensive analysis was conducted on the geometry, electronic, optical properties, work function, charge transfer interaction and adhesion energy of the g‐C3N4/MN4 heterostructures and concluded that g‐C3N4/FeN4 and g‐C3N4/CoN4 heterojunctions exhibit higher photocatalytic performance than individual units. The better photocatalytic activity can be attributed mainly by two facts; (i) the visible light absorption of both g‐C3N4/FeN4 and g‐C3N4/CoN4 interfaces are higher compared to its isolated analogs and (ii) a significant enhancement of band gap energy in g‐C3N4/FeN4 and g‐C3N4/CoN4 heterostructures limited the electron–hole recombination significantly. The potential of the g‐C3N4/MN4 heterojunctions as a photocatalyst for the water splitting reaction was assessed by examining its band alignment for water splitting reaction. Importantly, while the electronic and magnetic properties of MN4 systems were studied, this is the first example of inclusion of MN4 on graphene‐based material (g‐C3N4) for studying the photocatalytic activity. The state of the art DFT calculations emphasis that g‐C3N4/FeN4 and g‐C3N4/CoN4 heterojunctions are half metallic photocatalysts, which is limited till date. [ABSTRACT FROM AUTHOR]

This study presents the synthesis and characterization of upconverter nanostructures consisting of a perovskite host matrix, CaZrO 3 , co-doped with trivalent ytterbium (Yb3+) and europium (Eu3+), denoted as CaZrO 3 :Yb3+/Eu3+. Single-doped CaZrO 3 :Eu3+ samples were excited using a 394 nm UV source, while CaZrO 3 :Yb3+/Eu3+ samples were excited with a 980 nm diode laser source. Yb3+ ions efficiently absorb the 980 nm light and transfer the absorbed energy to the nearby ion Eu3+ ions, leading to the emission of visible light around 590, 614, and 655 nm, respectively. The emission spectra of Eu3+ ions exhibit an initial increase with increasing Yb3+ concentration, peaking at 7 mol%, followed by a decrease due to luminescence quenching. The decay lifetime of Eu3+ ions under 300 nm excitation decreases simultaneously with increasing Yb3+ concentration, indicating energy migration between Yb3+ and Eu3+. Detailed explanations of the energy transfer mechanism between Yb3+ and Eu3+ ions are provided, supported by equations and diagrams. This study provides valuable insights into the optimization of dopant concentrations for enhancing upconversion luminescence in CaZrO 3 :Yb3+/Eu3+ nanostructures, with 3 mol% Eu3+ concentration identified as optimal based on preliminary experiments. The findings presented in this paper contribute to the understanding of energy transfer processes in luminescence upconversion materials and highlight the potential of CaZrO 3 :Yb3+/Eu3+ nanostructures for applications in lighting, displays, and bio-imaging. This work represents a significant advancement in the field of upconversion luminescence emission, particularly in the utilization of CaZrO 3 codoped with Yb3+ and Eu3+, and lays the foundation for further research in this area. [ABSTRACT FROM AUTHOR]

The present work highlights the synthesis of graphene oxide (GO) modified polythiophene (PTh) for its application as an antibacterial agent as well as a visible light active photocatalyst. PTh was synthesized via the interfacial polymerization method using FeCl3 as initiator and then formulated as nanohybrids by mixing it in different weight ratios with graphene oxide (GO) i.e., 1 wt.%,3 wt.% and 5 wt. %. PTh and GO/PTh nanohybrids were characterized using FTIR, UV-visible, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) techniques. The polymerization of PTh as well as modification of PTh with GO was confirmed by IR studies, while the shifting of electronic transitions of PTH upon modification with GO were confirmed by the UV-visible studies. The degradation of dyes, Alizarin Yellow (AY), Basic Blue (BB) and Congo Red (CR) was carried out via sonophotocatalysis under visible light using PTh and GO/PTh as catalysts for a period of 60 min. The GO/PTh revealed higher degradation efficiency as compared to PTh. To evaluate its effectiveness as an antibacterial agent against Bacillus subtilis, disk diffusion inhibitory assay was carried out under dark and light conditions. The results showed that PTh and GO/PTh nanohybrids had bactericidal properties, regardless of light exposure. The results of the minimal inhibitory concentration (MIC) assay indicated the nanohybrid of 3-GO/PTh had the lowest MIC, followed by 1-GO/PTh and 5-GO/PTh. [ABSTRACT FROM AUTHOR]

[Display omitted] Selective oxidation of sulfur mustard gas (HD) to non-toxic sulfoxide by the visible-light-catalyzed generation of singlet oxygen (1O 2) is a promising degradation strategy. Although PCN-224 can absorb visible light, it suffers from rapid electron-hole recombination and low redox capacity, which limits the performance of HD degradation. Titanium dioxide (TiO 2) is an excellent photocatalyst but it lacks visible-light-activity in degrading HD. In this study, PCN-224@TiO 2 heterojunction with S-type core–shell structure was synthesized by in-situ growth method to prolong the visible light absorption capacity of TiO 2 and inhibit the rapid recombination of PCN-224. The interface formation and internal electric field were optimized by adjusting the Zr/Ti ratio to enhance the charge transfer, redox capacity, electron-hole separation, and visible light absorption. In this study, the formation of heterojunction composites based on Zr-O-Ti linkages is demonstrated by a series of characterization methods. It is demonstrated by experiments and theoretical calculations that PCN-224@TiO 2 can generate nearly 100 % 1O 2 under visible light conditions without a sacrificial agent, resulting in efficient and selective oxidation of 2-chloroethyl ethyl sulfide (CEES), a simulant of HD, to non-toxic sulfoxide form. [ABSTRACT FROM AUTHOR]

Transforming platform compounds with conventional catalysts, such as homogeneous and heterogeneous, into valuable chemicals encounters challenges associated with entailing high temperature/pressure and reusability during the reaction. To address these challenges, photocatalysis is one of the promising approaches, especially with visible‐light‐driven photocatalysts for selective transformation. A series of cerium‐doped TiO2 (CexTiO2; x=0.5, 1, 3 and 5 wt %) are prepared via a simple coprecipitation method for the cocatalyst‐free selective oxidation of 5‐hydroxymethylfurfural (HMF) to 2,5‐diformylfuran (DFF) under visible light illumination. Introducing Ce into the network to TiO2 generates impurity energy levels, reduces the band gap, and extends the spectral response range. This also causes slight distortion to the surface structure, thereby originating defective sites and various surface oxygen species, confirmed by X‐ray photoelectron spectroscopy and electron paramagnetic resonance studies. The HMF adsorption studies infer that HMF forms a surface complex with CeTiO2, facilitating the formation of ligand‐to‐metal charge transfer complex (LMCT) under visible light (~420 nm), which efficiently catalyzes the conversion of HMF (54.4 %) to DFF with a selectivity of >99 %. In‐situ DRIFTS and surface passivation studies provide insight into the interaction between HMF and surface acidic/basic sites along with hydroxyl groups of CeTiO2, which subsequently convert selectively to DFF. [ABSTRACT FROM AUTHOR]

Tandem processes are valuable tools that allow to build molecular complexity while reducing waste production and the number of steps of synthetic routes. In this work, the in situ photooxidation of benzyl alcohols to the corresponding benzaldehydes is coupled with a Knoevenagel condensation for the preparation of benzylidenemalononitrile derivatives. In this rapid one‐pot tandem process, sodium anthraquinone‐1,5‐disulfonate (SAS) and β‐alanine are employed as safe and inexpensive catalysts, while air is used as a terminal oxidant. Moreover, using water as reaction medium results in most cases in the precipitation of the target products, thus facilitating their isolation. [ABSTRACT FROM AUTHOR]

The need for carbon‐neutralization technologies has prompted significant interest in developing materials for CO2 reduction. Donor–acceptor (D–A) based flexible porous coordination polymers {[Zn(o‐phen)(ndc)].(guest)}n, (guest = anthracene = 1‐Ant, and pyrene = 1‐Pyr) are reported as photocatalysts for CO2RR, yielding higher order CH4 product. Electron‐rich anthracene (Ant) and pyrene (Pyr) guests are confined within nanopores, forming D–A charge transfer (CT) complexes with o‐phen ligand of the host. CT interaction enhances visible light absorption and modulates excitonic properties of the photocatalyst by electronic push‐pull effect (exciton binding energy 87 meV for 1‐Ant and 104 meV for 1‐Pyr). Electron donation capability varies from Pyr to Ant, affecting catalytic properties; 1‐Ant yields 1.24 mmolg−1 of CH4 (0.47 mmolg−1 for 1‐Pyr) with CO as minor product. A mixed‐metal multivariate PCP {[Zn0.55Co0.45(o‐phen)(ndc)].(Ant)}n, (1′‐Ant) prepared based on solid‐solution approach by substituting Zn(II) with redox‐active Co(II) enhances CH4 production (2.79 mmolg−1, ≈94% selectivity). D–A CT complex harvests visible light and channels electrons to Co(II) for CO2RR. In situ DRIFTS and theoretical studies elucidate Co(II) site's role in CO2 binding and stabilizing reaction intermediates. This work underscores guest‐modulated electron transfer in PCPs for tailoring catalytic properties by introducing a redox‐active metal in a multivariate approach. [ABSTRACT FROM AUTHOR]

Adaptive photonic films in response to external stimuli have broad applications in optical communications, sensing, and anticounterfeiting. Yet, it remains challenging to develop photonic structures with tailorable fine patterns that display broadband color changing under ambient conditions. Here a hydrogen‐bonded supramolecular cholesteric liquid crystalline polymer (CLCP) that is mediated by a binary solvent consisting of citric acid (CA) and water is presented. The incorporation of CA not only improves the long‐range order of CLCPs through evaporation‐induced self‐assembly but is also capable of tuning their helical pitch across the entire visible spectrum. The extent of hydration‐induced pitch expansion can be further manipulated by thermal crosslinking, enabling a unique patterning strategy based on mask‐free, programmable laser inscription. High‐precision photonic patterns are created onto CLCPs, which reveal themselves upon hydration in high visual contrast. The study offers a feasible and up‐scaling route toward tailoring environmentally adaptive CLCPs with tunable broadband coloration and highly programmable photonic patterns. [ABSTRACT FROM AUTHOR]

Developing highly efficient and low‐cost catalysts is an endless challenge in the field of producing H2 from ammonia borane (AB). Herein, the manufacture of yolk‐shell CuO‐Co3O4@Co3O4 nanocomposites are reported by using Cu2O@CuO as a template, in which CuO‐Co3O4 is encapsulated into the Co3O4 hollow nanocubes. Due to the unique morphology and built‐in electric field (BIEF) induced by the CuO‐Co3O4 interface, the CuO‐Co3O4@Co3O4 nanocomposites display remarkable catalytic activity in AB methanolysis. The turnover frequency (TOF) is 24.8 min‐1 in the absence of light and significantly increases to 33.9 min‐1 when exposed to visible light. The experimental and theoretical calculations demonstrate that charge migration from CuO to Co3O4 results in the formation of dual active sites (Cu and Co sites) in charge of adsorption and activation of CH3OH and AB, respectively. Visible light‐induced acceleration is likely caused by type‐II heterojunction, which allows a large number of photogenerated electrons to accumulate in the CuO conduction band. This effectively activates the adsorbed CH3OH on the Cu site, rendering it easier to break the O−H bond. A plausible reaction mechanism involved the activation of the O−H bond of CH3OH, as the RDS is proposed according to the FT‐IR and kinetic isotope effect (KIE) experiments. This work offers an avenue to rationally design high‐performance yolk‐shell catalyst for rapid hydrogen production from AB methanolysis reaction under visible light. [ABSTRACT FROM AUTHOR]

Structural engineering has proven effective in tailoring the photocatalytic properties of semiconductor nanostructures. In this work, a sophisticated double‐hollow yolk@shell nanostructure composed of a plasmonic, mobile, hollow Au nanosphere (HGN) yolk and a permeable, hollow CdS shell is proposed to achieve remarkable solar hydrogen production. The shell thickness of HGN@CdS is finely adjusted from 7.7, 18.4 to 24.5 nm to investigate its influence on the photocatalytic performance. Compared with pure HGN, pure CdS, a physical mixture of HGN and CdS, and a counterpart single‐hollow cit‐Au@CdS yolk@shell nanostructure, HGN@CdS exhibits superior hydrogen production under visible light illumination (λ = 400–700 nm). The apparent quantum yield of hydrogen production reaches 8.2% at 320 nm, 6.2% at 420 nm, and 4.4% at 660 nm. The plasmon‐enhanced activity at 660 nm is exceptional, surpassing the plasmon‐induced photoactivities of the state‐of‐the‐art plasmonic photocatalysts ever reported. The superiority of HGN@CdS originates from the creation of charge separation state at HGN/CdS heterojunction, the considerably long‐lived hot electrons of plasmonic HGN, the magnified electric field, and the advantageous features of double‐hollow yolk@shell nanostructures. The findings can provide a guideline for the rational design of versatile double‐hollow yolk@shell nanostructures for widespread photocatalytic applications. [ABSTRACT FROM AUTHOR]

A nonporous [Pb(tadt)]n (tadt = 1,3,4‐thiadiazole‐2,5‐dithiolate) coordination polymer, KGF‐9, with a 2D infinite (−Pb−S−)n structure has been previously reported as a precious‐metal‐free photocatalyst for selective CO2‐to‐formate conversion under visible light. In the present work, a microwave (MW)‐assisted solvothermal reaction is used to synthesize KGF‐9 with improved physicochemical properties and catalytic activity. Compared with KGF‐9 prepared by the previously reported methods, that prepared by the new synthesis route exhibited a greater specific surface area, greater crystallinity, and greater photoconductivity. These improved properties led to a drastic increase of the apparent quantum yield (AQY) for selective formate production, from 2.6 to 25% at 400 nm; this AQY represents a record‐high value among reported heterogeneous photocatalysts for CO2‐to‐formate conversion. Interestingly, the AQY for formate production is unchanged irrespective of the light intensity (0.04–14 mW cm−2), indicating little contribution of charge accumulation in the bulk during the reaction (i.e., indicating efficient charge transport to surface reactants). When composited with Ketjen Black, KGF‐9 enabled the electrochemical conversion of CO2 to formate in aqueous solution while maintaining a high selectivity. A high‐rate reduction of CO2 to formate with a total absolute current density of 200–300 mA cm−2 is achieved, with a Faradaic efficiency (FE) of >90%. [ABSTRACT FROM AUTHOR]

Photocatalytic CO2 reduction together with hydrogen generation is a promising approach to generate syngas, the photogenerated electron migration from photosensitizers to the catalytic active sites is the rate‐determining step. Herein, an integrative strategy is presented by covalently grafting metal complexes into donor–acceptor covalent triazine‐based frameworks. The catalytic active sites are integrated with the photosensitizer units by covalent linkages to form an extended π‐conjugated framework, which significantly reduces the energy barrier for the migration of the photogenerated charge carriers, resulting in high activity and durability in photocatalytic CO2 reduction into syngas under visible light irradiation. The CO and H2 evolution amounts in 1.5 h are 1086 and 1042 µmol g−1, respectively, which greatly surpass those in the host‐guest counterparts. Furthermore, selective adsorption for CO2 over N2 renders this photocatalytic system to be effective for syngas production from the simulated flue gas. This study provides new approaches to construct the integrative photocatalytic systems for solar‐to‐chemical energy conversion. [ABSTRACT FROM AUTHOR]

Owing to the unique features of high chemical and photostability, structurally colored materials can potentially replace organic dyes and pigments in many applications. The most common fabrication method of structural color materials is the “bottom‐up” self‐assembly approach. However, the assembled structures are easily damaged by external forces, leading to color fading or even disappearance. Therefore, it is still a challenge to fabricate structural colors that mimic the appearance of absorbing pigments without assembly processes. Inspired by the Steller's jay, non‐iridescent structurally colored nanopigments are created, which are composed of hollow SiO2 (H‐SiO2) microspheres with amorphous carbon on the inner wall of the shell and disordered metasurfaces on the shell layer. It is shown that the color originates from the synergistic effect of the disordered metasurfaces and the amorphous carbon layer, which can produce strong coherent scattered light and effectively absorb incoherently scattered light, respectively. Amazingly, the H‐SiO2 microspheres can maintain their structural colors even after grinding or being dispersed in water. What's more, through the additive color mixing of two base colors and precise tuning of their ratios, gradient structural colors that spanning the visible spectrum can be achieved. These features indicate promising prospects for the designed nanopigments. [ABSTRACT FROM AUTHOR]

Thirty-two coal (lignite-bituminous in rank) and carbonaceous shale samples, ranging from immature to overmature, were collected from the various coal-bearing basins (Saurashtra Basin, Bikaner Nagaur Basin, Damodar Basin, Mahanadi Basin, and Foreland Basin) in India and characterized petrographically (vitrinite reflectance and maceral composition), geochemically (total organic carbon and total sulfur) and chemically (Fourier Transform Infrared spectroscopy, FTIR). This paper explores utilization of FTIR study on bulk non-demineralized carbonaceous shale and coal to examine the interference between mineral and organic matter visible on FTIR spectra and application of such techniques to assess organic matter chemistry based on FTIR signal. Mineral matter is considerably affecting the organic matter FTIR signal in the region between 1700–1350 and 900–700 cm−1, while the 3100–2800 cm−1 region is unaffected. The general trends of organic matter evolution with thermal maturity, i.e. a decrease of aliphatic and oxygen-bearing groups and increase in aromatic signal, are visible in bulk non-demineralized samples; however, the interpretation of the signal is problematic due to the dilution-related signal weakening and region-specific overlapping. The quality of the FTIR signal is lower than the signal from demineralized kerogens or targeted specific maceral grains via combination of FTIR with microscopy. The spectra can still be useful for more qualitative aspects of FTIR, like assessment of organic functional groups, study of coal impurities, or as a complementary method in conjunction with other analytical techniques such as X-ray for mineral matter characterization. [ABSTRACT FROM AUTHOR]

Cu2O/TiO2 heterostructure is prepared by electrodepositing Cu2O on rutile phase TiO2 particles. The morphology, structural, and optical properties of Cu2O/TiO2 heterostructure are determined by scanning electron microscopy, Raman spectroscopy, X‐ray diffractometer, and UV–vis absorption spectrum. The Cu2O/TiO2 heterostructure photoelectrochemical‐type photodetector is constructed based on this heterostructure. Experimental results show that the photoresponsivity and visible light absorption of the Cu2O/TiO2 heterostructure are significantly enhanced compared to those of TiO2 and Cu2O which demonstrate that the Cu2O/TiO2 heterostructure with a special interfacial structure is conducive to accelerating the separation and transfer of photogenerated carriers. The photoresponsivity and photocurrent density of Cu2O/TiO2 can reach 154 μA W−1 and 15.6 μA cm−2 at 0 V. In addition, the photocurrent density of the Cu2O/TiO2 heterostructure steadily increases with the enhancement of irradiation power density. Moreover, no significant attenuation of the photocurrent density is observed in the prepared Cu2O/TiO2 heterostructure after 1800 s of photo‐on/off cycles. These results suggest that the Cu2O/TiO2 heterostructure‐based photodetector holds great potential in the photodetection field. [ABSTRACT FROM AUTHOR]