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The stability and durability of laser-induced graphene (LIG) patterns embedded in polymer substrates are significant for their practical application. However, most of currently reported LIG precursors are facing the dilemma of weak structural controllability, poor resistance to acid/base, or bad processability. In this work, we efficiently converted the synthesized poly (Ph-ddm) into LIG using a straightforward CO2 laser, aiming to find a potential LIG precursor with excellent durability under harsh conditions. The graphene structure of obtained LIG was confirmed by Raman spectra, scanning electron microscope (SEM), transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS). Results indicated that the poly (Ph-ddm)-based LIG showed a low sheet resistance of 35 Ω/sq as well as a high specific surface area of 883 m2/g. And due to the superior properties of poly (Ph-ddm), the LIG patterns exhibited excellent resistance to strong acid/base solutions and high adhesion on the substrate, which ensured their stable application under severe conditions. Besides, potential application of as-prepared LIG was demonstrated in well-performed supercapacitors and electrode for water splitting in an alkaline medium. Based on the results in this work, polybenzoxazine could be a promising precursor for stable and durable LIG preparation.

The photocatalytic reduction of carbon dioxide on nanoparticles of group VIII transition metals represents an emerging research area in recent years because of their promise in transforming carbon dioxide, a greenhouse gas, into value-added chemicals and fuels with the energy input of light. This mini review summarizes the fundamentals of the reduction of carbon dioxide and addresses how the photoexcitation of the metal nanoparticles can influence the reactions. The important roles of non-thermal hot electrons and photothermal effect in the photocatalytic reduction of carbon dioxide are highlighted, and the recent research reported in the literature are overviewed. There are still challenges in characterizing the photocatalytic reactions to distinguish the contributions of non-thermal and photothermal effects.

Selective aerobic oxidation of primary alcohols to aldehydes at low temperature and ambient condition is essential for many value-increasing industrial processes, although the low oxidizing power of the ambient oxygen represents the major challenge to widely implement this important reaction. Herein, we report that the oxidizing power of oxygen adsorbed on quantum-sized Rh nanocubes is significantly enhanced upon photo-illumination to accelerate the oxidation reaction with a selectivity of 100%. Light absorption in the Rh nanocubes anchored on large silica spheres leads to efficient generation of hot electrons in the Rh nanocubes, which are injected into the O–O bonds adsorbed on Rh surface to cleave them into adsorbed oxygen atoms with a much higher oxidizing power. The silica (SiOx) spheres enhance both the light absorption power and colloidal stability of the small Rh nanocubes, making the Rh/SiOx hybrid particles as a unique photocatalyst to readily promote the selective aerobic oxidation of alcohols to aldehydes.

This work aims at obtaining comprehensive information on the corrosion behaviour of AA2024-T3 in oxalic acid solutions under different concentrations (0.007–0.2 M) and pH (2–6). Various tests to characterise the corrosion behaviour are performed, including weight loss and electrochemical tests. Coupon surfaces are examined using infinite-focus microscopy, scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy, Raman spectroscopy and diffuse reflectance infrared Fourier transform spectroscopy. Corrosion rates, anodic and cathodic reaction kinetics are detailed to provide a fundamental understanding of the electrochemical behaviour of AA2024-T3 as a function of pH and oxalate concentration. The synergistic effect of pH and oxalate concentration on corrosion of AA2024-T3 is evaluated for both AA2024-T3 matrix and main intermetallics (i.e. Al–Cu–Mg and Al–Cu–Fe–Mn) and the electrochemical behaviour of each constituent element in AA2024-T3 is systematically studied.

A range of fully biobased unsaturated polyesters (bio-UPs) derived from 2,5-furandicarboxylic (FDCA), itaconic acid (IA), succinic acid (SA), and 1,3-propanediol (PD) were obtained via direct polycondensation. The chemical structures of the bio-UPs were identified by Fourier transfrom infrared spectroscopy and 1H NMR before they were cured together with a biobased, nonvolatile reactive diluent, guaiacol methacrylate (GM). The thermal and mechanical characterizations of the cured bio-UPs were evaluated using thermogravimetric analysis, 3-point bending tests, and dynamic mechanical analysis. Results showed that the thermal properties, flexural strength, and modulus of the cured bio-UPs were greatly improved after the introduction of FDCA. The temperature of 5% thermal weight loss reached 330 °C, and the flexural strength and modulus reached 122.8 and 3521 MPa, respectively. These results indicate that the bio-UPs have the potential to replace petroleum-based UPs.

Corrosion of aluminum alloy 2024 (AA 2024-T3) exposed to fungus Aspergillus niger cultured on glucose containing potato dextrose agar was studied in a high humidity and sterile atmospheric environment. The biofilm evaluation, weight loss measurement, quantitative pit analysis and corrosion product characterization were carried out. Results showed that, under this condition, the presence of A. niger accelerated corrosion process. The corrosion rate of AA 2024-T3 by A. niger was more than 4 times of that exposed to NaCl. Also, severe pitting corrosion, comparable to AA 2024-T3 exposed to NaCl, and aluminum depletion accompanied with copper enrichment were observed. Furthermore, the corrosion morphology was found to be related to the biofilm thickness. The dominant metabolite of A. niger under our experimental condition was identified to be oxalic acid, an aggressive corrodent that causes similar corrosion rate and corroded pit morphology as those observed in this study. Therefore, oxalic acid produced by A. niger under our specific experimental condition is believe to be the main cause for the corrosion of AA 2024-T3.

Silica nanoparticles, optically transparent in the visible spectral region, represent a class of dielectric antenna to tune the propagation and local field distribution of the visible light through surface scattering while the energy loss is minimized. The light scattering on the surface of silica nanoparticles include resonant scattering and random scattering that strongly depend on their geometry: spherical silica nanoparticles with the highest geometrical symmetry favors the light scattering resonances on the nanoparticle surfaces to promote resonant scattering while non-spherical silica nanoparticles mainly support random scattering. Both resonant scattering and random scattering of light on the silica nanoparticles are capable of enhancing the light absorption in quantum-sized metal nanocrystals attached to the surfaces of the silica nanoparticles. The contributions of resonant scattering and random scattering to the enhancement of light absorption have been compared and discussed. The understanding highlights the importance of the geometry of the silica nanoparticle antenna on the design and synthesis of composite materials for efficient light harvesting.

Fast and sensitive detection of dilute rare earth species still represents a challenge for an on-site survey of new resources and evaluation of the economic value. In this work, a robust and low-cost protocol has been developed to analyze the concentration of rare earth ions using a smartphone camera. The success of this protocol relies on mesoporous silica nanoparticles (MSNs) with large-area negatively charged surfaces, on which the rare earth cations (e.g., Eu3+) are efficiently adsorbed through electrostatic attraction to enable a “concentrating effect”. The initial adsorption rate is as fast as 4025 mg (g min)−1, and the adsorption capacity of Eu3+ ions in the MSNs is as high as 4730 mg g−1 (equivalent to ~ 41.2 M) at 70 °C. The concentrated Eu3+ ions in the MSNs can form a complex with a light sensitizer of 1,10-phenanthroline to significantly enhance the characteristic red emission of Eu3+ ions due to an “antenna effect” that relies on the efficient energy transfer from the light sensitizer to the Eu3+ ions. The positive synergy of “concentrating effect” and “antenna effect” in the MSNs enables the analysis of rare earth ions in a wide dynamic range and with a detection limit down to ~ 80 nM even using a smartphone camera. Our results highlight the promise of the protocol in fieldwork for exploring valuable rare earth resources. Electronic supplementary material The online version of this article (10.1007/s40820-018-0208-2) contains supplementary material, which is available to authorized users.