Poi Sim Khiew

Oceanic oil spills exert enduring adverse effects on marine ecosystems and human health. In contrast to conventional cleaning methods, advanced oil sorbents present a promising technology characterized by low cost, reduced environmental impact, and exceptional hydrophobicity and oleophilic properties for efficient oil removal from seawater. Despite these advantages, the efficacy of sorbents is hindered by highly viscous oil, impeding the oil/water separation process. To overcome this limitation, solar‐driven sorbents incorporating semiconductor materials are innovatively developed, leveraging increased temperatures to enhance crude oil absorption by reducing viscosity. Herein, a comprehensive review specifically focuses on various semiconductor‐functionalized sorbents for oil spill remediation, elucidating oil weathering and traditional cleaning methods to underscore the complexities and challenges in oil cleaning processes. An in‐depth discussion about the cleaning mechanisms of sorbents and the photothermal conversion processes facilitated by semiconductors is also provided. Additionally, it explores three coupling strategies—Joule heating and solar heating, photothermal effect, and magnetic effect, as well as photothermal and photocatalysis—that offer significant advancements in oil cleanup efficiency. Concluding with forward‐looking insights, the challenges and perspectives for the next generation of ocean oil spill removal technologies are proposed at the end.

Tackling water scarcity is a pressing challenge, propelling recent advancements in solar steam generation (SSG). Recently, 3D photoabsorbers have outperformed their 2D counterparts in recovering light and minimizing heat losses, enabling a surge in exploring 3D materials and designs. Herein, 3D structures are fabricated using polydopamine (PDA) functionalized carbonized palm fibers (PDA c‐fiber) to shed light on the degree of improvement in SSG efficiency compared to their 2D counterpart. Specifically, two 3D models, a cone, and a cylindrical cup, are chosen for their inherent features, including a hollow cavity, circular base, and curved surface. These architectural elements play a crucial role in trapping light, facilitating reflections, and efficiently converting solar energy to heat through the photothermal effect. Scaling palm fibers from 2D to 3D significantly boosts SSG efficiency, from 67.9% to 103.7%, with water evaporation rate enhanced from 1.171 kg m⁻² h⁻¹ to 1.869 kg m⁻² h⁻¹. Substantially, the 3D cup demonstrates superior photothermal performance primarily attributed to its heat recovery feature of the cup wall structure and circular basal area, enabling prolonged light‐to‐heat conversion. These findings provide valuable insights and foundation for developing efficient solar‐driven 3D upcycled photoabsorbers in the future.

Wearable energy storage devices require high mechanical stability and high-capacitance flexible electrodes. In this study, we design a flexible supercapacitor electrode consisting of 1-dimensional carbon nanotubes (CNT), cellulose nanofibrils (CNF), and manganese dioxide nanowires (MnO₂ NWs). The flexible and conductive CNT/CNF-MnO₂ NWs suspension was first prepared via ultrasonic dispersion approach, followed by vacuum filtration and hot press to form the composite paper electrode. The morphological studies show entanglement between CNT and CNF, which supports the mechanical properties of the composite. The CNT/CNF-MnO₂ NWs electrode exhibits lower resistance when subjected to various bending angles (−120–+120°) compared to the CNT/CNF electrode. In addition, the solid-state supercapacitor also shows a high energy density of 38 μWh cm⁻² and capacitance retention of 83.2% after 5000 cycles.

Solar steam generation has drawn high levels of attention from the research community in recent years due to its wide application and abundantly available energy source—sunlight. To the best of the author's knowledge, a specialized overview of photothermal semiconductor solar steam generation has not been conducted to date. In this review, the recently reported solar evaporators using metal oxide semiconductors as the photoabsorber material are investigated, from the perspective of nanostructure, synthesis method, and installation method. A timeline sequence map is generated with the CiteSpace analysis tool to visualize the trend of metal oxide semiconductors as photoabsorbers. The nanostructure of metal oxide semiconductor is emphasized, due to its significant effect on regulating photothermal efficiency in solar steam generation. In addition, other considerations are suggested to enable a fair evaluation of future synthesized photoabsorbers, including cost, stability, reproducibility, recyclability, and regenerative ability. A brief summary of divergent application of solar steam generation is conducted to show the merits of solar steam generation, as well to provide insights for production of photoabsorbers targeted to varying usage and scenarios. Furthermore, the challenges and opportunities of metal oxide solar steam generation system are elaborated from the viewpoint of the authors, with the aim to provide useful insights for future development of photothermal solar steam generation.

Supercapacitors (SCs) have been widely investigated in the realm of energy resulting from their superior long lifespan and remarkable power density. However, their practical usage is limited because of the high effective resistance and relatively low energy density. Electrode material is crucial for determining the performance of SCs, so the innovation and development of advanced electrode materials is particularly important. Metal-organic frameworks (MOFs) and carbonaceous materials, including MOF-derived carbons and carbon nanotubes (CNTs), are befitting as electrode active materials for SCs on the strength of the unique features of high porosity, tunable structures, and easy formation of composites with other compounds. Hence, great efforts were devoted on the synthesis strategies and structural modifications of electrodes to enhance the performance of SCs. In this review, the recent innovations in the realm of SCs, including the application of pristine and derivatives of MOFs as SC electrode materials, were extensively studied. Furthermore, the functions and electrochemical performance of various MOFs and their derivatives (e.g., MOF-derived carbons) were analyzed accordingly. Lastly, the innovations and application of CNTs as SC electrode active materials are systematically summarized. This review highlights the electrochemical performance of some advanced MOF- and carbon-based materials, and the critical factors for SC electrode active materials to achieve excellent electrochemical performance in the application of energy storage systems.