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Photoassisted energy storage is a promising approach to realizing the utilization of solar power, and the reasonable design of a photoassisted supercapacitor with photosensitive materials is one of the efficient ways to realize solar power conversion and storage. Herein, we design a photoassisted supercapacitor electrode (TiO2/CF) by integrating a photoelectrode (TiO2) and a capacitive electrode (CF) together, which achieves photoelectric synergistic charge storage. It is found that spherical TiO2precursors will crash, expand, integrate, stretch, and tear, forming a reticulated structure. Reticulated TiO2guarantees illumination, which can boost the utilization of solar power. The TiO2/CF electrode exhibits a considerable (1.9-fold) increase in capacitance performance under light conditions as compared to dark conditions. Furthermore, this TiO2/CF photoassisted supercapacitor electrode exhibits an excellent cycle stability of about 99.19% after 5000 cycles. Moreover, the enhancement mechanism is elaborated as follows: these high-energy photoelectrons will participate in charge transfer to increase the total energy of the process, thereby enhancing capacitance performance. In addition, these photoelectron–hole pairs act as additional charge carriers to favor charge accumulation. This work may offer new prospects for developing photoassisted energy supply systems for the utilization of solar power.

The high effective nano-hybrid pour point depressant (PPD) has attracted extensive attention for its potential application in improving the cold flow properties of diesel fuel. In this paper, the nano-hybrid PPD was prepared by melt-blending method using three different alkyl chain lengths (i.e., tetradecyl, hexadecyl, and octodecyl) of n-alkyl methacrylate-maleic anhydride copolymers (R1MC-MA, R1 = C14, C16, C18) and SiO2nanoparticles. The effect of those nano-hybrid PPDs on the cold filter plugging point (CFPP) and solidifying point (SP) depressing of diesel fuel were studied. Results indicated that nano-hybrid PPD showed much better performance on diesel fuel. The diesel fuel treated with 0.2 wt% C14MC-MA/SiO2nano-hybrid PPD exhibited the best depression in CFPP and SP by 6 °C and 18 °C, respectively, which higher than that of single C14MC-MA. Viscosity-temperature curves and polarized optical microscopy were conducted to explore the performance mechanism; and results presented that nano-hybrid PPD of C14MC-MA/SiO2could effectively lower the low-temperature viscosity, and modify the crystallization behavior and crystal morphology of diesel. Therefore, the cold flow properties of diesel were significantly improved.

Nonspecific binding and weak spectral discernment are the main challenges for surface-enhanced Raman scattering (SERS) detection, especially in real sample analysis. Herein, molecularly imprinted polymer (MIP)-based core–shell AuNP@polydopamine (AuNP@PDA-MIP) nanoparticles (NPs) are designed and immobilized on an electrochemically reduced MoS2-modified screen-printed electrode (SPE). This portable electrochemical–Raman interface offers the dual functions of electrokinetic preseparation (EP) and MIP trapping of charged molecules so that a reliable SERS recognition with molecular selectivity and high sensitivity can be achieved. Core–shell AuNP@PDA-MIP NPs can be controllably synthesized, possess predesigned specific recognition, and provide “hot spots” at the junction of NPs. The introduction of an electric field enables the autonomous exclusion and separation of similarly charged molecules as well as attraction and concentration of the oppositely charged molecules by electrostatic attraction. Subsequently, the specific MIP recognition cavities allow selective adsorption of targets on the interface without the interference of analogues. Owing to the distinctive design of the multiple coupling separation, trapping, and enrichment strategies, the MIP-based SERS-active interface can be used for label-free detection of charged molecules in real samples without pretreatment. As a proof-of-concept study, label-free SERS detection of charged phthalate plasticizers (PAEs) was demonstrated with a detection limit as low as 2.7 × 10–12M for dimethyl phthalate (DMP) and 2.3 × 10–11M for di(2-ethylhexyl) phthalate (DEHP). This sensing strategy for in situSERS analysis of charged pollutants or toxins holds vast promises for a wide range of in-field applications.

Activated N/P codoped carbon (A-NPC) materials with ultrahigh specific surface areas (SSA) and hierarchical porous structures were synthesized by a green and cheap method to enhance the electrochemical performance of electrical double-layer capacitors. Waste durian peel was used as a carbon precursor, (NH4)2HPO4as N and P sources, and KOH as an activator. The obtained porous carbon material had an ultrahigh SSA (3416 m2g–1), a hierarchical porous structure (84 vol % micropores), and appropriate N (2.17 at. %) and P (0.48 at. %) doping amounts. Synergy among these characteristics enabled the A-NPC to exhibit exciting specific capacitance (383.4 F g–1at 0.5 A g–1), ideal rate performance (255.6 F g–1at 20 A g–1), and fantastic cyclic performance (98.3% capacitance retention after 10 000 cycles at 5 A g–1) in the three-electrode device. This material could provide an energy density of 25.3 W h kg–1when the power density was 400.5 W kg–1, to all-solid-state symmetrical capacitors and presented good cycle performance with a cycle retention rate of 97.6% at 2 A g–1after 5000 cycles. A-NPC has potential applications in the supercapacitor field given its excellent properties.

High-efficiency pour point depressants (PPDs) for diesel fuel were obtained using a series of tetradecyl methacrylate-N-α-methacrylamide copolymers (C14MC-NMLR) with different molar ratios synthesized through radical polymerization of tetradecyl methacrylate (C14MC) and various forms of N-α-methacrylamide (NMLR, R = -phenyl, -naphthyl, -cyclohexyl, -14a, -16a, -18a). The copolymers were characterized by Fourier transform infrared spectroscopy, 1H nuclear magnetic resonance, and thermogravimetric analysis. Results showed that diesel treated with C14MC-NML-phenyl (9:1) and C14MC-NML-14a (6:1) presented better cold flow properties at 2000 ppm, and the reductions in cold filter-plug point (ΔCFPP) and solid point (ΔSP) were (23 and 10 °C) and (22 and 11 °C) at 2000 ppm, respectively. The depressive effects further improved after compounding. When they were combined at a 1:4 mass ratio, PPDC-6 presented the best depressive effects, and the ΔCFPP and ΔSP reached 25 and 11 °C at 1000 ppm dosage and 28 and 15 °C at 2000 ppm dosage, respectively. Additionally, the crystallization behavior and crystal morphology of each treated diesel were explored.

The addition of benzyl methacrylate–methacrylate copolymers to diesel significantly improves its cold flow properties, but it is always limited by a large dosage. To improve the depressing efficiency further, N-vinyl-2-pyrrolidone (NVP), as a polar nitrogenous compound, was introduced, and a series of methacrylate-benzyl methacrylate-N-vinyl-2-pyrrolidone terpolymers (R1MC-MB-NVP) was synthesized at different molar ratios (1:1:1, 5:1:1, 10:1:1, 15:1:1, and 20:1:1). Those terpolymers were characterized by Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H-NMR), and thermogravimetric analysis (TGA). Their effects on the cold filter plugging point (CFPP) and solid point (SP) of diesel fuel were evaluated. With 2000 ppm of C14MC-MB-NVP (15:1:1), treated diesel has an improved depression on the solid point (SP) by 23 °C, whereas C16MC-MB-NVP (5:1:1) treated diesel indicates an improved reduction on the CFPP by 14 °C. However, combined PPDs (PPDC-6) of C14MC-MB-NVP (15:1:1) and C16MC- MB-NVP (5:1:1) in a mass ratio of 1:4 present the best depressing effects, and the SP and CFPP of diesel treated with 2000 ppm PPDC-6 are decreased by 29 and 15 °C, respectively. Furthermore, the action mechanism of PPDs was studied by polarizing optical microscopy, differential scanning calorimetry, and rheology analysis. Results showed that the introduction of NVP into PPDs not only improves the solubility and dispersity of wax crystals in diesel but also facilitates the formation of hydrogen bonds between PPDs and other polar substances and further disperses wax crystals into wax crystal molecules by the hydrogen bond ability.

In this paper, various nonionic surfactants (NS) with different ethylene oxide (EO) numbers and tail lengths and its binary blends with anionic surfactants (AS) were used as emulsifiers in naphthenic oil to form the microemulsion metalworking fluids (MWFs) by formulation triangle method. The effects of the chemical structure of surfactants on the stability of naphthenic oil-based MWFs were investigated.

ABSTRACTElectroless Ni–Mo–P composite coatings with or without ultrasonic field were successfully deposited. The Sodium molybdate concentration was changeable to receive various Mo and P contents. Compared with the absence of ultrasound field, the coatings obtained smoother surface and higher Mo and P contents. The microhardness was determined by Vickers diamond indentation. The results showed that the hardness improved with increasing molybdenum and phosphorus content. The sample revealed the optimum hardness (886 HV) as it possesses 8 wt-% of Mo and 14 wt-% of P. Furthermore, the coatings exhibited higher hardness under ultrasound field. The corrosion resistance was analysed by potentiodynamic polarisation. The results showed that the corrosion resistance was enhanced in the increase of molybdenum. The sample with the highest Mo content (10 wt-%) showed the best corrosion resistance (5.81 μA cm−2). In addition, the coatings with ultrasound field have an influence on improving the corrosion resistance of the coating.

Electroless Ni–Mo–P composite coatings with or without ultrasonic field were successfully deposited. The Sodium molybdate concentration was changeable to receive various Mo and P contents. Compared with the absence of ultrasound field, the coatings obtained smoother surface and higher Mo and P contents. The microhardness was determined by Vickers diamond indentation. The results showed that the hardness improved with increasing molybdenum and phosphorus content. The sample revealed the optimum hardness (886 HV) as it possesses 8 wt-% of Mo and 14 wt-% of P. Furthermore, the coatings exhibited higher hardness under ultrasound field. The corrosion resistance was analysed by potentiodynamic polarisation. The results showed that the corrosion resistance was enhanced in the increase of molybdenum. The sample with the highest Mo content (10 wt-%) showed the best corrosion resistance (5.81 µA cm-2). In addition, the coatings with ultrasound field have an influence on improving the corrosion resistance of the coating.

Efficient charge transfer and light-trapping units are pivotal prerequisites in the realm of Ti-based photoanode photoelectrochemical (PEC) water splitting. In this work, we successfully synthesized a ternary carbon quantum dots/Bi2S3quantum dots/Nb-doped TiO2nanotube arrays (CQDs/Bi2S3/TiNbO) composite photoanode for PEC water splitting. CQDs/Bi2S3/TiNbO composite photoanode exhibited a considerably elevated photocurrent density of 8.80 mA cm–2at 1.23 V vs the reversible hydrogen electrode, which was 20.00 times better than that of TiO2(0.44 mA cm–2). Furthermore, the CQDs/Bi2S3/TiNbO composite photoanode attested to exceptional stability, maintaining 92.54% of its initial current after 5 h of stability measurement. Nb-doping boosted the electrical conductivity, facilitating charge transfer at the solid–liquid interface. Moderate amounts of Bi2S3quantum dots (QDs) and CQDs deposited on TiNbO provided abundant active sites for the electrolyte–photoanode interaction. Simultaneously, Bi2S3QDs and CQDs synergistically functioned as light-trapping units to broaden the light absorption range from 396 to 530 nm, stimulating increased carrier generation within the composite photoanode. In comparison with pristine TiO, CQDs/Bi2S3/TiNbO photoanodes possessed a superior ability to promote interfacial reactions. This study may provide a strategy for developing high-performance Ti-based photoanodes with efficient charge transfer and light trapping units for highly driving solar-to-hydrogen conversion.

ABSTRACTWe successfully obtained sonicated Ni–B–Ce coating on the surface of low carbon steel (Q235) through ultrasonic-assisted electroless plating with the deposition time of 60 minutes. The coatings were heat treated at 300, 500 and 800°C for 2 hours. The results showed the Ni–B–Ce coating changed from amorphous to crystallised and produced Ni3B and Ni2B phases after heat treatment. The addition of Ce changed the crystallisation temperatures of Ni–B–Ce coating after heat treatment to 562 and 692°C, which differed from those of Ni–B coating (298, 371 and 411°C). It also improved the activation energy to 156.85 and 214.11 kJ mol−1, which was much higher than those of Ni–B coating (32.23, 25.80 and 50.69 kJ mol−1). In addition, the 800°C annealed coatings showed notable improvement in hardness (1212 HV10) and corrosion properties (3.01 μA cm−2) which could be ascribed to the formation of Ni3B and Ni2B phases.

We successfully obtained sonicated Ni–B–Ce coating on the surface of low carbon steel (Q235) through ultrasonic-assisted electroless plating with the deposition time of 60 minutes. The coatings were heat treated at 300, 500 and 800°C for 2 hours. The results showed the Ni–B–Ce coating changed from amorphous to crystallised and produced Ni3B and Ni2B phases after heat treatment. The addition of Ce changed the crystallisation temperatures of Ni–B–Ce coating after heat treatment to 562 and 692°C, which differed from those of Ni–B coating (298, 371 and 411°C). It also improved the activation energy to 156.85 and 214.11 kJ mol-1, which was much higher than those of Ni–B coating (32.23, 25.80 and 50.69 kJ mol-1). In addition, the 800°C annealed coatings showed notable improvement in hardness (1212 HV10) and corrosion properties (3.01 µA cm-2) which could be ascribed to the formation of Ni3B and Ni2B phases.

Ammonia is a zero‑carbon, and high-energy storage feedstock. The Haber-Bosch process of industrial ammonia synthesis is the predominant method of ammonia synthesis worldwide. However, the shortages of high energy consumption and high pollution of Haber-Bosch process affect the global environment. The electrochemical nitrogen reduction reaction (ENRR), which is environmentally friendly and can be carried out at room temperature and pressure, may be an alternative method. In recent years, researchers have used different materials such as noble metal, non-noble metal, single-atom, and defect materials to obtain higher NH3yield rates and better Faradaic efficiency. With the continued efforts of the researchers, it is believed that the industrialization of ENRR will be achieved in the future.

MXenes have shown great promise in high-efficiency energy storage on account of superior electrical conductivity and outstanding mechanical properties. However, the practical applications of MXenes in electrochemical energy storage are limited by layer restacking and surface oxidation issues. Herein, a unique sandwich-like Na2Ti3O7nanosheet/Ti3C2MXene composite (NTO@MXene) with an expanded interlayer spacing of MXene has been fabricated by one-step simultaneous alkalization and oxidation. The NTO@MXene with a unique structure shortens the ion diffusion distance and promotes electrolyte infiltration, which is favorable for high-performance rechargeable batteries. As a result, the NTO@MXene composite as an anode electrode for lithium-ion batteries delivered exceptional rate performance (159 mAh g–1at 4 A g–1) and long-life cycling performance (capacity retention of nearly 100% at 4 A g–1after 1200 cycles). When used as a sodium-ion battery anode, the electrode also achieved an extraordinary capacity of 103 mAh g–1at 0.1 A g–1and an exceptional capacity retention of 70% at a high current density of 2 A g–1after 3000 cycles.