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Mesoporous silica SBA-15 has emerged as a promising adsorbent and separation material due to its unique structural and physicochemical properties. To further enhance its performance, various surface modification strategies, including metal oxide and noble metal incorporation for improved catalytic activity and stability, organic functionalization with amino and thiol groups for enhanced adsorption capacity and selectivity, and inorganic–organic composite modification for synergistic effects, have been extensively explored. This review provides a comprehensive overview of the recent advances in the surface modification of SBA-15 for adsorption and separation applications. The synthesis methods, structural properties, and advantages of SBA-15 are discussed, followed by a detailed analysis of the different modification strategies and their structure–performance relationships. The adsorption and separation performance of functionalized SBA-15 materials in the removal of organic pollutants, heavy metal ions, gases, and biomolecules, as well as in chromatographic and solid–liquid separation, is critically evaluated. Despite the significant progress, challenges and opportunities for future research are identified, including the development of low-cost and sustainable synthesis routes, rational design of SBA-15-based materials with tailored properties, and integration into practical applications. This review aims to guide future research efforts in developing advanced SBA-15-based materials for sustainable environmental and industrial applications, with an emphasis on green and scalable modification strategies.

The exceptional photoelectromagnetic characteristics of rare-earth elements contribute significantly to their indispensable position in the high-tech industry. The exponential expansion of the demand for high-purity rare earth and related compounds can be attributed to the swift advancement of contemporary technology. Nevertheless, rare-earth elements are finite and limited resources, and their excessive mining unavoidably results in resource depletion and environmental degradation. Hence, it is crucial to establish a highly effective approach for the extraction and reclamation of rare-earth elements. Adsorption is regarded as a promising technique for the recovery of rare-earth elements owing to its simplicity, environmentally friendly nature, and cost-effectiveness. The efficacy of adsorption is contingent upon the performance characteristics of the adsorbent material. Presently, there is a prevalent utilization of porous adsorbent materials with substantial specific surface areas and plentiful surface functional groups in the realm of selectively separating and recovering rare-earth elements. This paper presents a thorough examination of porous inorganic carbon materials, porous inorganic silicon materials, porous organic polymers, and metal–organic framework materials. The adsorption performance and processes for rare-earth elements are the focal points of discussion about these materials. Furthermore, this work investigates the potential applications of porous materials in the domain of the adsorption of rare-earth elements.

Light-emitting diode (LED)-based visible light communication (VLC) is a great promising high-speed wireless access solution due to its low power consumption, no electromagnetic interference, large available bandwidth, and no authentication required. However, visible light cannot be used directly as an information source, and must be combined with other communication technologies to avoid becoming an information island. In hybrid power line and visible light communication (HPV) system, power line communication (PLC) can be used to deliver data to VLC transmitters. Multiple users can share the same time and frequency resources to provide higher spectral efficiency using non-orthogonal multiple access (NOMA) method than traditional multiple access method. Therefore, we investigate the power allocation strategy for a downlink of HPV system based on NOMA. Our goal is to maximize achievable sum rate of the HPV system while considering user fairness. To solve this optimization problem, we present an optimal power allocation (OPA) algorithm that finds optimal solution by transforming the non-convexity of the original formulated model into the convex programming. Numerical results show that the proposed OPA algorithm significantly outperforms the gain ratio power allocation (GRPA) and the fixed power allocation (FPA) algorithm in terms of the sum rate, and improves the fairness among users.