Kwok Feng Chong

The persistent corrosion of metal surfaces poses a significant engineering challenge, including material degradation, loss of metal-structural integrity, and massive maintenance costs in various industrial, medical, and aerospace applications. Microorganisms such as archaea, bacteria, fungi, and microalgae can directly or indirectly influence metal corrosion. The degree of corrosiveness and corrosion healing varies depending on the microbe, medium, and metal substrate characteristics. Several attempts have been made to reveal answers to all questions about MIC. The published reports focused on testimonial failures and laboratory or field tests under varied situations. This review offers an overview of the most recent MIC research and emphasizes the scarcity of data on MIC detection, estimation, and the most recent approaches for MIC management. The review extends previously reported works and summarizes efforts for better understanding and cutting off MIC management in advanced technologies. Furthermore, it concludes with a final discussion of the current and future drawbacks and protective systems for preventing microbial-induced corrosion.

With the rising demand for efficient, sustainable and scalable energy storage, researchers are continuously exploring innovative materials for next-generation supercapacitors. Among these, transition metal coordination polymer (TMCP)-derived materials have emerged as promising candidates due to their high porosity, redox activity and structural adaptability. These materials offer significant potential for energy storage, but challenges like low electrical conductivity, structural instability and limited charge retention have restricted their widespread application. To overcome these hurdles, researchers have developed transformation strategies such as carbonization, phosphorization, sulfidation and oxide formation, enhancing the conductivity, stability and overall electrochemical performance of TMCPs. This review investigates the latest breakthroughs in TMCP-derived electrode materials, highlighting key advancements in synthesis techniques, structural engineering and hybrid material integration to improve charge transport and long-term durability. The incorporation of green chemistry principles, such as low-temperature synthesis, the use of non-toxic precursors, and strategies for recycling or reducing harmful byproducts, is highlighted, consequently promoting the fabrication of environmentally friendly supercapacitors. Furthermore, it explores how nanostructured designs and composite materials are unlocking new possibilities for high-performance supercapacitors. It also provides a perspective on the future of TMCPs in energy storage by fusing theoretical insights with experimental evidence. Theoretical frameworks like density functional theory and emerging machine learning models are other methods employed to better understand redox behaviour and drive material design. It addresses present issues and suggests viable future directions for their useful application.

Background:: Cobalt oxide nanocubes have garnered significant attention as potential supercapacitor electrodes due to their unique structural and electrochemical properties. The spent lithium-ion batteries (LiBs) are considered as zero-cost source for cobalt oxide production. Objective:: The aim of this work is to recover cobalt oxide from spent LiBs and study its electrochemical performance as a supercapacitor electrode material. Method:: This study uses an electrodeposition method to obtain cobalt oxide honeycomb-like anodes coated on Ni foam substrates from spent Li-ion batteries for supercapacitors applications. The effect of annealing temperature on the cobalt oxide anode has been carefully investigated; 450 ºC annealing temperature results in nanocubes on the surface of the cobalt oxide electrode. X-ray diffraction confirmed the formation of the Co3O4-NiO electrode. Results:: The Co3O4-NiO nanocubes electrode has shown a high specific capacitance of 1400 F g-1 at 1 A g-1 and high capacitance retention of ~96 % after 2250 cycles at a constant current density of 10 A g-1 compared to 900 F g-1 at 1 A g-1 as for prepared Co3O4 honeycomb. Conclusion:: This strategy proves that the paramount importance of Co3O4-NiO nanocubes, meticulously synthesized at elevated temperatures, as a supremely effective active material upon deposition onto transition metal foam current collectors, establishing their indispensability for supercapacitor applications.

Achieving a high energy density and long-cycle stability in energy storage devices demands competent electrochemical performance, often contingent on the innovative structural design of materials under investigation. This study explores the potential of transition metal selenide (TMSe), known for its remarkable activity, electronic conductivity, and stability in energy storage and conversion applications. The innovation lies in constructing hollow structures of binary metal selenide (CoNi-Se) at the surface of reduced graphene oxide (rGO) arranged in a three-dimensional (3D) morphology (CoNi-Se/rGO). The 3D interconnected rGO architecture works as a microcurrent collector, while porous CoNi-Se sheets originate the active redox centers. Electrochemical analysis of CoNi-Se/rGO based-electrode reveals a distinct faradic behavior, thereby resulting in a specific capacitance of 2957 F g^-1 (1478.5 C g^-1), surpassing the bare CoNi-Se with a value of 2149 F g^-1 (1074.5 C g^-1) at a current density of 1 A g^-1. Both materials exhibit exceptional high-rate capabilities, retaining 83% of capacitance at 10 A g^-1 compared to 1 A g^-1. In a two-electrode coin cell system, the device achieves a high energy density of 73 Wh kg^-1 at a power density of 1500 W kg^-1, stating an impressive 90.4% capacitance retention even after enduring 20,000 cycles. This study underscores the CoNi-Se/rGO composite's promise as a superior electrode material for high-performance energy storage applications.

Glycopolymer materials have emerged as a significant biopolymer class that has piqued the scientific community's attention due to their potential applications. Recently, they have been found to be a unique synthetic biomaterial; glycopolymer materials have also been used for various applications, including direct therapeutic methods, medical adhesives, drug/gene delivery systems, and biosensor applications. Therefore, for the next stage of biomaterial research, it is essential to understand current breakthroughs in glycopolymer-based materials research. This review discusses the most widely utilized synthetic methodologies for glycopolymer-based materials, their properties based on structure–function interactions, and the significance of these materials in biosensing applications, among other topics. When creating glycopolymer materials, contemporary polymerization methods allow precise control over molecular weight, molecular weight distribution, chemical activity, and polymer architecture. This review concludes with a discussion of the challenges and complexities of glycopolymer-based biosensors, in addition to their potential applications in the future. Graphical Abstract

A membrane composed of polyethylene terephthalate nanofiber and multi-walled carbon nanotubes (PET NF-MWCNTs) composite is used to adsorb methylene blue (MB) dye from an aqueous solution. Scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction techniques are employed to study the surface properties of the adsorbent. Several parameters affecting dye adsorption (pH, MB dye initial concentration, PET NF-MWCNTs dose, and contact time) are optimized for optimal removal efficiency (R, %) by using the Taguchi L25 (5⁴) Orthogonal Array approach. According to the ANOVA results, pH has the highest contributing percentage at 71.01%, suggesting it has the most significant impact on removal efficiency. The adsorbent dose is the second most affected (12.08%), followed by the MB dye initial concentration of 5.91%, and the least affected is the contact time (1.81%). In addition, experimental findings confirm that the Langmuir isotherm is well-fitted, suggesting a monolayer capping of MB dye on the PET-NF-MWCNT surface with a maximum adsorption capacity of 7.047 mg g⁻¹. Also, the kinetic results are well-suited to the pseudo-second-order model. There is a good agreement between the calculated (q_e) and experimental values for the pseudo-second-order kinetic model.