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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]

Phenol waste treatment is vital in industries such as polymer production, coal gasification, refinery, and coke production. Photocatalytic technology using semiconductor materials offers an effective and ecofriendly approach to degrade phenol. TiO2 P25 is a widely used photocatalyst, known for its cost-effectiveness, favorable optical and electronic properties, high photoactivity, and photostability. The PHOTOREAC application, a recently developed MATLAB-based software, simulates the degradation of phenol using visible light. A study that combines existing literature and research revealed that pH significantly influences photocatalytic activity, with an optimum pH of 7 for TiO2 P25-mediated phenol degradation. The recommended photocatalyst concentration ranged from 0 to 10 g/L for reactor volumes between 25 and 60 mL, and from 0 to 5 g/L for 100-mL reactors. Phenol wastewater volume and light intensity also impact degradation efficiency. Adequate oxygen supply, achieved through bubbling and mixing, is essential for the formation of radical compounds. The Ballari kinetic model proved to be the most suitable for phenol degradation with TiO2 P25. Thus, by combining PHOTOREAC simulations with experimental data, the treatment process could be optimized to achieve higher degradation efficiency and estimate the treatment time for specific waste degradation levels. This study contributes to the advancement of phenol waste treatment and the development of improved photocatalytic wastewater treatment technologies. [ABSTRACT FROM AUTHOR]

Methane is one of the promising alternatives to non-renewable petroleum resources since it can be transformed into added-value hydrocarbon feedstocks through suitable reactions. The conversion of methane to methanol with a higher chemical value has recently attracted much attention. The selective oxidation of methane to methanol is often considered a "holy grail" reaction in catalysis. However, methanol production through the thermal catalytic process is thermodynamically and economically unfavorable due to its high energy consumption, low catalyst stability, and complex reactor maintenance. Photocatalytic technology offers great potential to carry out unfavorable reactions under mild conditions. Many in-depth studies have been carried out on the photocatalytic conversion of methane to methanol. This review will comprehensively provide recent progress in the photocatalytic oxidation of methane to methanol based on materials and engineering perspectives. Several aspects are considered, such as the type of semiconductor-based photocatalyst (tungsten, titania, zinc, etc.), structure modification of photocatalyst (doping, heterojunction, surface modification, crystal facet re-arrangement, and electron scavenger), factors affecting the reaction process (physiochemical characteristic of photocatalyst, operational condition, and reactor configuration), and briefly proposed reaction mechanism. Analysis of existing challenges and recommendations for the future development of photocatalytic technology for methane to methanol conversion is also highlighted. [ABSTRACT FROM AUTHOR]

Agriculture waste has created massive challenges over the last few decades and yet also opportunities. This work aimed to produce high-quality biochar from rubberwood waste with calorific properties close to subbituminous coal. Using a tubular vertical reactor, the effects of rubberwood particle size (wood chips and shredded wood), torrefaction temperature (220, 260, and 300 °C), and residence time (30, 60, and 90 minutes) on the quality of torrefied rubberwood were studied. The results showed that the mass loss of the rubberwood increased as the temperature increased. Also, the particle size and residence time increased due to excessive devolatilization. A higher fixed-carbon content and calorific value as well as lower moisture and volatile-matter content in the biochar were achieved by increasing the torrefaction temperature and residence time in comparison to the untreated sample (raw rubberwood). The highest fixed-carbon content and calorific value were found to be 56.7% and 6313 kcal/kg, respectively, for the wood chip particles that were torrefied at 300 °C for 60 minutes. Based on the Van Krevelen diagram, torrefaction of woodchip rubberwood at 300 °C with a residence time of 60 minutes demonstrated the optimum condition to generate a product with properties that are close to those of subbituminous rank coal. [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]

Solar-intercalation batteries, which are able to both harvest and store solar energy within the electrodes, are a promising technology for the more efficient utilization of intermittent solar radiation. However, there is a lack of understanding on how the light-induced intercalation reaction occurs within the electrode host lattice. Here, an in operando synchrotron X-ray diffraction methodology is introduced, which allows for real-time visualization of the structural evolution process within a solar-intercalation battery host electrode lattice. Coupled with ex situ material characterization, direct correlations between the structural evolution of MoO3 and the photo-electrochemical responses of the solar-intercalation batteries are established for the first time. MoO3 is found to transform, via a two-phase reaction mechanism, initially into a sodium bronze phase, Na0.33MoO3, followed by the formation of solid solutions, Na xMoO3 (0.33 < x < 1.1), on further photointercalation. Time-resolved correlations with the measured voltages indicate that the two-phase evolution reaction follows zeroth-order kinetics. The insights achieved from this study can aid the development of more advanced photointercalation electrodes and solar batteries with greater performances. [ABSTRACT FROM AUTHOR]

Disposal of palm oil mill effluent (POME), which is highly polluting from the palm oil industry, needs to be handled properly to minimize the harmful impact on the surrounding environment. Photocatalytic technology is one of the advanced technologies that can be developed due to its low operating costs, as well as being sustainable, renewable, and environmentally friendly. This paper reports on the photocatalytic degradation of palm oil mill effluent (POME) using a BiVO4 photocatalyst under UV-visible light irradiation. BiVO4 photocatalysts were synthesized via sol-gel method and their physical and chemical properties were characterized using several characterization tools including X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), surface area analysis using the BET method, Raman spectroscopy, electron paramagnetic resonance (EPR), and UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS). The effect of calcination temperature on the properties and photocatalytic performance for POME degradation using BiVO4 photocatalyst was also studied. XRD characterization data show a phase transformation of BiVO4 from tetragonal to monoclinic phase at a temperature of 450 °C (BV-450). The defect site comprising of vanadium vacancy (Vv) was generated through calcination under air and maxima at the BV-450 sample and proposed as the origin of the highest reaction rate constant (k) of photocatalytic POME removal among various calcination temperature treatments with a k value of 1.04 × 10−3 min−1. These findings provide design guidelines to develop efficient BiVO4-based photocatalyst through defect engineering for potential scalable photocatalytic organic pollutant degradation. [ABSTRACT FROM AUTHOR]

Phenol acts as a pollutant even at very low concentrations in water. It is classified as one of the main priority pollutants that need to be treated before being discharged into the environment. If phenolic-based compounds are discharged into the environment without any treatments, they pose serious health risks to humans, animals, and aquatic systems. This review emphasizes the development of advanced technologies for phenol removal. Several technologies have been developed to remove phenol to prevent environmental pollution, such as biological treatment, conventional technologies, and advanced technologies. Among these technologies, heterogeneous catalytic ozonation has received great attention as an effective, environmentally friendly, and sustainable process for the degradation of phenolic-based compounds, which can overcome some of the disadvantages of other technologies. Recently, zeolites have been widely used as one of the most promising catalysts in the heterogeneous catalytic ozonation process to degrade phenol and its derivatives because they provide a large specific surface area, high active site density, and excellent shape-selective properties as a catalyst. Rational design of zeolite-based catalysts with various synthesis methods and pre-defined physiochemical properties including framework, ratio of silica to alumina (SiO2/Al2O3), specific surface area, size, and porosity, must be considered to understand the reaction mechanism of phenol removal. Ultimately, recommendations for future research related to the application of catalytic ozonation technology using a zeolite-based catalyst for phenol removal are also described. [ABSTRACT FROM AUTHOR]

The palm oil industry produces liquid waste called POME (palm oil mill effluent). POME is stated as one of the wastes that are difficult to handle because of its large production and ineffective treatment. It will disturb the ecosystem with a high organic matter content if the waste is disposed directly into the environment. The authorities have established policies and regulations in the POME waste quality standard before being discharged into the environment. However, at this time, there are still many factories in Indonesia that have not been able to meet the standard of POME waste disposal with the existing treatment technology. Currently, the POME treatment system is still using a conventional system known as an open pond system. Although this process can reduce pollutants' concentration, it will produce much sludge, requiring a large pond area and a long processing time. To overcome the inability of the conventional system to process POME is believed to be a challenge. Extensive effort is being invested in developing alternative technologies for the POME waste treatment to reduce POME waste safely. Several technologies have been studied, such as anaerobic processes, membrane technology, advanced oxidation processes (AOPs), membrane technology, adsorption, steam reforming, and coagulation. Among other things, an AOP, namely photocatalytic technology, has the potential to treat POME waste. This paper provides information on the feasibility of photocatalytic technology for treating POME waste. Although there are some challenges in this technology's large-scale application, this paper proposes several strategies and directions to overcome these challenges. [ABSTRACT FROM AUTHOR]

The large‐scale application of electrochemical reduction of CO2, as a viable strategy to mitigate the effects of anthropogenic climate change, is hindered by the lack of active and cost‐effective electrocatalysts that can be generated in bulk. To this end, SnO2 nanoparticles that are prepared using the industrially adopted flame spray pyrolysis (FSP) technique as active catalysts are reported for the conversion of CO2 to formate (HCOO−), exhibiting a FEHCOO− of 85% with a current density of −23.7 mA cm−2 at an applied potential of −1.1 V versus reversible hydrogen electrode. Through tuning of the flame synthesis conditions, the amount of oxygen hole center (OHC; SnO●) is synthetically manipulated, which plays a vital role in CO2 activation and thereby governing the high activity displayed by the FSP‐SnO2 catalysts for formate production. The controlled generation of defects through a simple, scalable fabrication technique presents an ideal approach for rationally designing active CO2 reduction reactions catalysts. [ABSTRACT FROM AUTHOR]

Active and cost‐effective catalyst materials are required for electrochemical CO2 reduction reactions (CO2RR) which, to date, are proving elusive. Here, the direct electrochemical conversion of CO2 to liquid products with a high overall Faradaic efficiency (FE) by utilizing a unique 3D, heterostructured copper electrode (referred as Cu sandwich) that is obtained via a simple two‐step treatment of commercially available copper foam is reported. The designed catalyst achieves an FE toward liquid products of >50% at an applied potential as low as −0.3 V versus reversible hydrogen electrode. The improved selectivity of the heterostructured Cu sandwich electrode at low overpotentials is attributed to the greater exposure of engineered Cu+/Cu2+ interfaces (present on composite nanowires) and higher oxygen vacancy defects. Moreover, the rationally designed heterostructures prevent the Cu2O species from being reduced during CO2RR enabling the catalyst to demonstrate enhanced CO2RR activity with prolonged stability. A 3D heterostructured copper electrode (Cu sandwich) for CO2 reduction reactions (CO2RR) is fabricated by a simple two‐step treatment of commercially available copper foam. The catalyst demonstrates a high selectivity toward ethanol and methanol production during CO2RR. The improved selectivity of the Cu sandwich can be explained by the presence of Cu+/Cu2+ interfaces and oxygen vacancy defects. [ABSTRACT FROM AUTHOR]

In article number 1700545, Jason Scott, Rose Amal, Yun Hau Ng, and co‐workers report the establishment of a solar‐chargeable intercalation battery and an operando synchrotron X‐ray diffraction technique that enables realtime tracking of the dynamic structural change of a solar battery electrode from a photo‐intercalation reaction. By analyzing the structural prerequisite for light‐induced intercalation reaction, novel materials with tailored electrode structures and conductivities can be designed to enhance solar battery technology. [ABSTRACT FROM AUTHOR]

A TiO 2 /TiOF 2 composite has been synthesized through a hydrothermal method and characterized using X-ray diffraction, Raman spectroscopy, UV-vis diffuse reflectance, SEM-EDX, TEM, and N 2 adsorption-desorption isotherms. The percentage of exposed facet [001] and the composition of TiO 2 /TiOF 2 in the composite were controlled by adjusting the amount of HF and hydrothermal temperature synthesis. Three crucial factors in the photocatalytic conversion of methane to methanol, including the photocatalyst, electron scavenger (FeCl 2 ), and H 2 O 2 were evaluated using a statistical approach. All factors were found to have a significant impact on the photocatalytic reaction and exhibited a synergistic effect that enhanced methanol production. The highest methanol yield achieved was 0.7257 μmole h -1 g cat -1 . The presence of exposed [001] and fluorine (F) in the catalyst is believed to enhance the adsorption of reactant molecules and provide a more oxidative site. The Fenton cycle reaction between FeCl 2 and H 2 O 2 was attributed to reducing recombination and extending the charge carrier lifetime. Incorporating Ag into the TiO 2 /TiOF 2 catalyst results in a significant 2.2-fold enhancement in methanol yield. Additionally, the crucial involvement of hydroxyl radicals in the comprehensive reaction mechanism highlights their importance in influencing the process of photocatalytic methane-to-methanol conversion., Competing Interests: There is no conflict of interests existing in the manuscript submission, and it is approved by all of the authors for publication. All the authors listed have approved the manuscript to be enclosed., (This journal is © The Royal Society of Chemistry.)

Defect engineering of semiconductor photocatalysts is considered as an evolving strategy to adjust their physiochemical properties and boost photoreactivity of the materials. Here, hydrogenation and UV light pre-treatment of TiO 2 /SiO 2 composite with the ratio of 9 : 1 (9TiO 2 /1SiO 2 ) were conducted to generate Ti 3+ and non-bridging oxygen holes center (NBOHC) defects, respectively. The 9TiO 2 /1SiO 2 composite exhibited much higher photocatalytic water splitting than neat TiO 2 and SiO 2 as a consequence of the electronic structure effects induced by the defect sites. Electron paramagnetic resonance (EPR) indicated that hydrogenated and UV light pre-treated of 9TiO 2 /1SiO 2 boosted a higher density of Ti 3+ and NBOHC defect which could serve to suppress photogenerated electron-hole pair recombination and act as shallow donors to trap photoexcited electron. Overall, both defect sites in 9TiO 2 /1SiO 2 delivered advantageous characteristic relative to neat TiO 2 and SiO 2 with the finding clearly illustrating the value of defect engineering in enhancing photocatalytic performance., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The large-scale application of electrochemical reduction of CO 2 , as a viable strategy to mitigate the effects of anthropogenic climate change, is hindered by the lack of active and cost-effective electrocatalysts that can be generated in bulk. To this end, SnO 2 nanoparticles that are prepared using the industrially adopted flame spray pyrolysis (FSP) technique as active catalysts are reported for the conversion of CO 2 to formate (HCOO - ), exhibiting a FE HCOO - of 85% with a current density of -23.7 mA cm -2 at an applied potential of -1.1 V versus reversible hydrogen electrode. Through tuning of the flame synthesis conditions, the amount of oxygen hole center (OHC; Sn≡O●) is synthetically manipulated, which plays a vital role in CO 2 activation and thereby governing the high activity displayed by the FSP-SnO 2 catalysts for formate production. The controlled generation of defects through a simple, scalable fabrication technique presents an ideal approach for rationally designing active CO 2 reduction reactions catalysts., Competing Interests: The authors declare no conflict of interest.