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The contemporary focus on global concerns such as carbon dioxide (CO2) emissions impacting the environment and contributing to the energy crisis has prompted exploration into alternatives, with photocatalysis emerging as a potential solution. This research involved the development of a PT (TiO2) photocatalyst, synthesized through the hydrothermal method and enhanced with double co‐catalysts of copper and nickel via the wet impregnation technique. The characteristics of the resulting photocatalysts were comprehensively examined using various techniques, including XRD, Raman, UV‐Vis DRS, surface area and pore analysis, SEM‐EDX, HRTEM, XPS, PL, and EPR. The characterization outcomes revealed that the PT phase comprised anatase, brookite, and rutile. The incorporation of double co‐catalysts was evident through the emergence of new peaks in the XRD diffraction pattern, corroborated by SEM, HRTEM, and XPS analysis. In the activity test, CNT‐4 (Cu−Ni/TiO2‐400) exhibited the highest methanol yield at 772.41 μmole g−1 h−1, followed by CONTT‐4 (CuO−NiTiO3/TiO2‐400) with 750.38 μmole g−1 h−1 after three hours of irradiation using a 300 W xenon lamp, while methanol in PT formed only after three hours of irradiation. The presence of co‐catalysts significantly influenced methanol yield, attributed to the increased active sites for the reaction and the reduced band gap, impacting light absorption optimization and suppressing electron‐hole recombination. In CNT‐4, the formation of Ti3+ associated with oxygen vacancies facilitated the generation of more products. [ABSTRACT FROM AUTHOR]

Carbon capture technologies are imperative for addressing climate change objectives. Among the available solutions, five post-combustion capture technologies stand out for their efficacy in trapping CO2 from flue gas emissions: chemical absorption, adsorption, membrane separation, cryogenic distillation, and electrochemical processes. Their implementation spans both laboratory investigations and pilot/commercial applications. This review systematically examines these five CO2 capture technologies, emphasizing their progression in industrial applications. Current research endeavors are explored, and pivotal challenges are underscored. When addressed, they can enhance both performance and economic feasibility. Comparative analyses indicate that while adsorption, membrane, and cryogenic processes have seen pilot/commercial applications, chemical absorption is the most cost-effective and established method, accounting for an operational capacity of approximately 50 million tons of CO2 annually. Remarkably, electrochemical devices have exhibited superior performance at the laboratory scale, achieving CO2 removal efficiencies exceeding 98% with a simple activation mechanism. Comprehensive strategies addressing operational costs and device configurations are essential to transition this technology to larger scales. [ABSTRACT FROM AUTHOR]

Palm oil processing can result in different food products like cooking oil and margarine. Nevertheless, these food products might contain harmful contaminants, namely 3‐monochloropropane‐1,2‐diol ester (3‐MCPDE) and glycidyl ester (GE), which can negatively affect animal organs and potentially cause human cancer. Therefore, the objective of this study was to lower the concentration of 3‐MCPDE and GE in refined, bleached, and deodorized palm oil (RBDPO) using zeolite as an adsorbent. Adsorption experiments were conducted in a batch reactor, varying the percentage of adsorbents, temperature, type of zeolite, and the use of a mixture of zeolite and activated carbon (AC). The sample was analyzed before and after adsorption using gas chromatography–mass spectroscopy (GC–MS) to confirm the concentration alteration of 3‐MCPDE and GE. The study showed that the most effective temperature for adsorption was 35°C and used a zeolite percentage of 2%. Beta zeolites resulted in the highest removal of 3‐MCPDE (86%) among the evaluated zeolites attributed to their elevated pore volume, Si/Al ratio, and overall acidity strength. Through a synergistic combination of beta zeolite and AC, the removal percentage of 3‐MCPDE was enhanced to 94%, with a corresponding 75% reduction in GE. This study paves the way for addressing 3‐MCPDE and GE concerns in RBDPO by combining zeolite and AC. [ABSTRACT FROM AUTHOR]

There is a notable emphasis on the development of photocatalysts to degrade antibiotics, such as sulfamethoxazole (SMX), in aquatic environments due to their persistence and associated toxicological impacts. In this study, BiOBr photocatalysts were synthesized by incorporating in-situ Bi doping. Various Bi/BiOBr composites were produced through a hydrothermal method at varying temperatures and subsequently characterized using X-ray diffraction (XRD), UV-vis diffuse reflectance spectroscopy (UV-vis DRS), X-ray fluorescence (XRF), and nitrogen adsorption-desorption isotherm. The characterization data revealed that the Bi-metal began to emerge at a hydrothermal temperature of 180 °C (BB180) in the BiOBr-based semiconductor and completed its conversion to Bi-metal at a hydrothermal temperature of 270 °C (BB270). This transformation leads to the generation of Bi3+ in conjunction with oxygen vacancies, acting as active electron traps and enhancing the separation efficiency of light-induced electron-hole pairs. This results in a narrow band gap of Bi/BiOBr photocatalyst, increasing its sensitivity towards visible light. BB180 exhibited the highest photocatalytic rate in the degradation of SMX with a removal efficiency of 74.35% within 4 hours of reaction under Xenon lamp irradiation and an apparent rate constant of 6.5 x 10-3 min-1, surpassing the commercial TiO2 Degussa P25. This finding opens up a new pathway for the development of a catalyst responsive to visible light, specifically designed for the detoxification of antibiotics in wastewater. [ABSTRACT FROM AUTHOR]

Addressing the escalating concerns over increasing carbon dioxide (CO2) emissions and their detrimental effect on the environment has become global attention. One promising alternative to tackle this issue involves utilizing photocatalytic technology to convert CO2 into more valuable chemicals, with methane (CH4) being a notable targeted product. This article presents a comprehensive review of the exploration of TiO2‐based photocatalysts by researchers worldwide for such applications. The initial discussion revolves around fundamental aspects, including the basic principles, thermodynamics, kinetics, and reaction mechanisms involved in the process. Additionally, to enhance the efficiency of these aspects, support from other factors is necessary, including the physicochemical properties of the photocatalyst through various catalyst synthesis methods (such as sol‐gel, precipitation, hydrothermal, and solvothermal) as well as employing catalyst modification techniques (such as doping, heterojunction, and surface modifications). Furthermore, the review delves into an examination of parameters that influence the photocatalytic CO2 reduction to methane process, as they directly impact the yield and selectivity of the desired product. Ultimately, the existing challenges and potential research opportunities that could provide comprehensive solutions for the applications of photocatalytic technology for converting CO2 to CH4 as a whole are elaborated in this review. [ABSTRACT FROM AUTHOR]

Renewable‐electricity‐powered electrocatalytic CO2 reduction reactions (CO2RR) have been identified as an emerging technology to address the issue of rising CO2 emissions in the atmosphere. While the CO2RR has been demonstrated to be technically feasible, further improvements in catalyst performance through active sites engineering are a prerequisite to accelerate its commercial feasibility for utilization in large CO2‐emitting industrial sources. Over the years, the improved understanding of the interaction of CO2 with the active sites has allowed superior catalyst design and subsequent attainment of prominent CO2RR activity in literature. This review tracks the evolution of the understanding of CO2RR active sites on different electrocatalysts such as metals, metal‐oxides, single atoms, metal‐carbon, and subsequently metal‐free carbon‐based catalysts. Despite the tremendous research efforts in the field, many scientific questions on the role of various active sites in governing CO2RR activity, selectivity, stability, and pathways are still unanswered. These gaps in knowledge are highlighted and a discussion is set forth on the merits of utilizing advanced in‐situ and operando characterization techniques and machine learning (ML). Using this technique, the underlying mechanisms can be discerned, and as a result new strategies for designing active sites may be uncovered. Finally, this review advocates an interdisciplinary approach to discover and design CO2RR active sites (rather than focusing merely on catalyst activity) in a bid to stimulate practical research for industrial application. [ABSTRACT FROM AUTHOR]