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Copper metal is essential to our production process, but it is highly corrosive in an ammonia environment and must be highly valued. Anti-corrosion coating is a simple and cost-effective method of preventing metal corrosion. In this study, a composite silane coating was prepared on copper using an impregnation method with mercaptopropyltriethoxysilane (TPTES) as the silane substrate and graphene oxide (GO) modified with isophorone diisocyanate (IPDI) or isocyanatopropyltriethoxysilane (IPTS) as filler to protect the copper from ammonia corrosion. The coating samples were hanging tested against ammonia corrosion by setting up two corrosive environments: ammonia gas and ammonia water. After 20 days of corrosion, the surfaces of the TPTES/IPDI-GO and TPTES/IPTS-GO coatings remained unchanged under both ammonia environments and the corrosion rate was consistently low at 2–3 μm/y. Additionally, the coating exhibited high protective qualities according to the electrochemical impedance spectroscopy (EIS) test in a 3.5% NaCl solution, which is attributed to the good dispersion that improves the densification and regularity of the coating. Meanwhile, IPTS-GO has a greater binding force with the coating matrix due to the increased number of reactive sites, resulting in further improved corrosion protection. This study provides an idea for research on ammonia-resistant coatings. [Display omitted] • Silane coatings are prepared by a simple impregnation method, with a simple process and wide range of applications. • 2、The corrosion hanging test was set up with two corrosive environments: ammonia gas and ammonia water. • 3、TPTES/IPDI-GO and TPTES/IPTS-GO silane coating samples show good protection after 20 days of corrosion in ammonia environments. • 4、 Further enhancement of the coating's ammonia corrosion resistance by increasing the number of reaction sites around the GO that are more readily available for binding to the coating substrate. [ABSTRACT FROM AUTHOR]

[Display omitted] • The composite membrane has superhydrophilicity and underwater superoleophobicity. • The composite membrane demonstrates enhanced UV cleaning capabilities. • The composite membrane achieves over 100% flux recovery rate under UV irradiation. • The composite membrane can continuously separate emulsion with excellent parameters. • The composite membrane shows superior oil resistance and durability. In the emulsion separation process, the adhesion of oil-contamination severely hampers the long-term operation of ceramic membranes, and photocatalytic membranes present a promising approach to mitigate membrane fouling and enhance membrane performance. The present study describes the fabrication of a novel Al 2 O 3 @GO-TiO 2 composite photocatalytic membrane through a two-step dip-coating method. TiO 2 particles were uniformly deposited onto the surface of the pristine membrane via a thermal coating method, while the pleated graphene oxide (GO) formed a laminar-flow-like coating through stirring-ultrasonication, ultimately being stably anchored to the composite membrane's surface by co-built connections with TiO 2. Due to the successful coating of hydrophilic groups, the composite membrane exhibited super hydrophilic-underwater superoleophobic properties to separate stable water-in-diesel emulsions with excellent permeation flux (4347.17 L∙m−2∙h−1) and oil removal rate (94.98 %). The composite membrane showed excellent oil resistance stability and durability in severe environment hydrodynamic washout and cycling tests. In addition, the combined modification of GO-TiO 2 endowed the composite membranes with strong photocatalytic ability, which made the membranes exhibit a good recovery of membrane performance in the separation of oilfield-produced water (OPW). The thick oil layer was completely removed by •OH, •O 2 – and 1O 2 generated by UV irradiation excitation. After 6 h of operation, the flux and oil removal rate of the Al 2 O 3 @GO-TiO 2 membrane were 31.91 % and 2.1 % higher than those of the Al 2 O 3 @TiO 2 membrane, demonstrating enhanced light self-cleaning performance. The exceptional oil–water separation capability coupled with its efficient photocatalytic degradation potential positions the ceramic membrane as a promising solution for treating actual OPW. [ABSTRACT FROM AUTHOR]

The lightweight and efficient electromagnetic wave (EMW) absorption materials have been a popular research topic. In this work, MnO 2 @graphene (MnGr) nanofibers with core-shell structure were synthesized by a one-step hydrothermal method. This one-dimensional linear structure was further self-assembled into a three-dimensional hierarchical MnGr aerogel network structure due to the interlayer forces of graphene sheets. The addition of graphene greatly enhances the interfacial polarization. The significant differences in electronic structure and work function between the outer graphene layer and the inner MnO 2 layer greatly enhance the interfacial polarization. The formation of 3D hierarchical MnGr aerogel network structure constructs more fast electron transport channels. With the addition of graphene oxide at 7.5 wt% of the theoretical yield of MnO 2 , MnGr-7.5 exhibits excellent wave absorption properties. The effective absorption bandwidth (EAB) can reach 6.40 GHz at 2.2 mm. And the minimum reflection loss (RL min) is − 41.3 dB at 1.8 mm and 17.36 GHz. Finite element physical simulation is used to simulate the response of 3D conductive network to electromagnetic wave. Through calculation, it is found that the inter-lap network structure is beneficial to enhance the loss. The low-cost MnO 2 compounded with a small amount of graphene has excellent wave absorption performance and a great application prospect. • A three-dimensional hierarchical MnO 2 @graphene (MnGr) aerogel network structure is constructed. • The fabricated MnO 2 @graphene aerogel has the advantages of light weight, wide effective bandwidth and strong absorption. • Using COMSOL simulation to study the response of conductive networks to electromagnetic wave. [ABSTRACT FROM AUTHOR]

Traditional water-based PV/T systems have low heat storage density, high PV backsheet temperatures, and low energy utilization in practical applications. In this work, nanoparticles were applied to improve thermal conductivity and simultaneously emulsions were added to enhance energy storage density of the conventional heat transfer media. Furthermore, the synergistic effect of nanocomposite Phase Change Material Emulsions (PCME) as the heat transfer medium on the thermoelectric efficiency of PV/T was studied in a real system. Specifically, the water-based 30 % paraffin emulsions with graphene oxide (GO) concentration of 0.01, 0.02 and 0.03 wt% were prepared by ultrasonic stirring and their thermophysical properties were characterized. The results show that the 30 wt% paraffin emulsion with addition of 0.02 wt% GO has the phase change temperature of 35 °C, latent heat of 42.93 J/g, thermal conductivity of 0.505 W/(m·K) and viscosity coefficient of 0.91. It shows the thermal efficiency of the paraffin/GO emulsion increased by 92.28 %, the electrical efficiency increased by 8.87 %, the comprehensive efficiency increased by 45.75 %, and 15.8 % increase in heat collection for the heat exchange tank in comparison with the water. It is concluded application of PCME would improves the thermoelectric performance of the system than traditional water-based PV/T systems. • Applying paraffin emulsions with GO nanoparticles to a practical PV/T system. • Optimal nanocomposite paraffin emulsion is selected by performance testing. • Comparing the performance and pumping consumption with water-based PV/T systems. • Greater improvement in thermoelectric efficiency of PV/T systems compared to water. [ABSTRACT FROM AUTHOR]