Photocatalyst Materials Research Articles

Construction of BaTiO3/g-C3N4 S-type heterojunctions for photocatalytic degradation of Tetracycline

Tetracycline, one of the antibiotics, is widely used in a number of fields, and residual Tetracycline in the environment can be a serious threat to the safety of environmental ecosystems. In this paper, a series of BaTiO3/g-C3N4 composite photocatalysts were designed and synthesized by a combination of solvent volatilization and high-temperature thermal polymerization using BaTiO3 and g-C3N4 as raw materials. Construction of S-type heterojunction between BaTiO3 and g-C3N4 lead to the formation of built-in electric field synergistically with BaTiO3 own ferroelectric polarization to promote the separation efficiency of photogenerated electron-hole pairs. When Tetracycline was used as the target pollutant, the degradation rate of the BTO900,2/CN catalyst was 91.88 %, which was 142.73 times higher than the 7 % of BaTiO3, which was a significant improvement over the photocatalytic performances of both BaTiO3 and g-C3N4. This provides new ideas for studying BaTiO3-based photocatalyst materials with high photogenerated carrier separation efficiency.

Synthesis of Nanoparticle ZnO via Chemical Reduction Using Singkil (<i>Premna serratifolia linn</i>) Leaf Extract as Photocatalytic

Nanoparticles are one of the widely studied research topics. ZnO nanoparticles have numerous benefits, such as photocatalysts and antibacterial applications. Methylene blue, which a highly dangerous and pollutes the environment and human health, is mostly used as a coloring dye in the textile industry. The use of biodegradation to treat textile waste is time-consuming and less effective. Applying photocatalysts using semiconductor materials is a more efficient method than conventional approaches for decomposing organic waste. One environmentally friendly method is green synthesis, which involves the use of microorganisms, enzymes, and plant extracts in the fabrication process. In this study, the green synthesis using chemical reduction of Premna serratifolia linn leaf extract was used to produce ZnO nanoparticles. The objective of this study is to investigate the effect of temperature on the fabrication of ZnO nanoparticles and their photocatalytic performance. Zinc nitrate tetrahydrate was used as a precursor, and the furnace temperature was varied at 400, 500, and 600 °C. The obtained ZnO was then tested using scanning electron microscopy (SEM), X-ray diffractometry (XRD), and Fourier transforms infrared spectrophotometry (FTIR). Moreover, the photocatalytic test was evaluated by examining the degradation efficiency of methylene blue using UV light. The XRD analysis indicated that the ZnO nanoparticles had crystallite sizes ranging between 44-60 nm. The SEM morphological test showed that the ZnO particles had a nano-sized spherical shape. The FTIR test results demonstrated the presence of ZnO peaks around 520 cm‑1. The performance of photocatalytic activity under UV light irradiation was significantly affected by tuning the temperatures. It was observed that the photocatalytic activity increased with increasing temperature, and methylene blue degradation efficiency reached 50% at a temperature of 600 °C. The ability of ZnO as a photocatalyst material was also evaluated by recycling the used material two times, where there was no significant change in photocatalytic performance.

Selective conversion of CO2 to CO using blue TiO2 with an r-GO shell and quantitative measurement of excited electrons with four-wave mixing microspectroscopy

The conversion of CO2 into hydrocarbon or syngas (CO) using sunlight can address numerous current environmental issues and future challenges in the energy domain. Although numerous visible light-responsive photocatalysts have been reported, the quantum yield remains limited. Furthermore, analytical tools are yet to be established for quantitatively monitoring the amount of excited electrons, which play a critical role in catalytic reactions. The results of this study revealed that the presence of a reduced graphene oxide (r-GO) shell on blue-TiO2 (b-TiO2) considerably improves the photocatalytic performance in selectively converting CO2 into CO under visible light. The formation of the r-GO shell on b-TiO2 narrowed the b-TiO2 bandgap. Moreover, the r-GO shell increased the absorption of visible light and facilitated electron transfer, resulting in approximately eight times the CO yield from b-TiO2@r-GO compared to that of TiO2. The presence of the r-GO shell improved the photocatalytic stability of b-TiO2. Furthermore, four-wave mixing microspectroscopy was performed to analyze the amount of excited electrons. The results of microscopy revealed the amount of excited electrons in b-TiO2@r-GO was approximately 35 times that of TiO2. These results not only proposed a strategy for increasing the stability and efficiency of TiO2-based photocatalysts but also are useful for evaluating the improvement of photocatalyst materials.

First-Principles prediction of Janus γ-Ge2STe as a potential multifunctional material for photocatalysts, photovoltaic, and piezoelectric applications

First-Principles prediction of Janus γ-Ge2STe as a potential multifunctional material for photocatalysts, photovoltaic, and piezoelectric applications

Sunlight-activated composite TiO2-F-V-Mo materials for photodegradation of the organic pollutant methylene blue

F-doped TiO2 photocatalyst materials were prepared using solid-state and sol-gel synthesis with varying weight percentages of LiF or NH4F. Subsequently, molybdate and vanadium oxide were added to the prepared powders to create composite photocatalysts with reduced bandgap energy, enhancing light absorption in the visible region of the spectrum, which is essential for effective photocatalytic activity using sunlight. The synthesized powders were characterized by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and specific surface area using the BET method. The crystallization and anatase-to-rutile phase transformation of the powders were verified by X-ray diffraction (XRD), and the composite nanoparticles were further investigated by transmission electron microscopy (TEM). The photocatalytic activity of the F-doped commercial TiO2, sol-gel synthesized TiO2, and prepared composite powders was evaluated through the photocatalytic degradation of methylene blue (MB) in water under ultraviolet (UV), UV–visible, and sunlight irradiation. The results indicated that the incorporation of Molybdenum and Vanadium significantly influenced the photocatalytic efficiency by substantially reducing the bandgap of this composite photocatalyst. The LiF-doped TiO2 powders synthesized by sol-gel using TTIP, and doped with vanadium and molybdenum, activated by sunlight, exhibited high performance in MB degradation compared to commercial TiO2 and undoped synthesized TiO2 powders, achieving an optimal degradation rate of 7.26 × 10⁻⁹ mol per gram of photocatalyst.

Facile solvothermal approach to design synergetic effect between the BiVO4 and TiS2 to boost up the Z-scheme photocatalytic performance for water treatment and hydrogen production

An innovative and economically practical method was developed to create unique BiVO4/TiS2 structures in an ecologically friendly way. Novel BiVO4/TiS2 composites are created by combining as synthesized BiVO4 and freshly prepared titanium disulfide (TiS2). The BiVO4/TiS2 composites were thoroughly evaluated to investigate their physical, optical, morphological, and photochemical characteristics. Pure BiVO4 material, TiS2 nanostructures, and BiVO4/TiS2 nanocomposites were evaluated for their photocatalytic capabilities by observing the deterioration of MB beneath natural solar irradiation. The BiVO4/TiS2@50 % composite exhibited highly improved sunlight-striving photocatalytic activities. The cycle stability of the as-produced BiVO4/TiS2@50 % photocatalyst material and active species effects that areparticipating in the photocatalytic coursehave also been studied. The decrease in charge recombination time and increased visible light absorption of the BiVO4/TiS2@50 % may be the causes of the enriched photocatalytic activity. A thorough examination encompassing empirical evidence and theoretical computations, culminated in developing a Z scheme photocatalytic mechanism. The results obtained from repeated cycling experiments and electrochemical impedance spectroscopy provided additional support for this mechanism. Furthermore, after five consecutive cycles, BiVO4/TiS2@50 % photocatalyst sample exhibited commendable stability in an aqueous environment. Utilizing a highly efficient photocatalyst material (BiVO4/TiS2@50 %) further elucidates the degradation mechanism and scavenging effect of MB dyes. The BiVO4/TiS2@50 % photocatalyst achieved a hydrogen production rate of 15.5 mmolg−1h−1, which is higher than the single BiVO4 and TiS2 and other prepared composites. The excellent reductive and oxidative capabilities of our best material (BiVO4/TiS2@50 %) and its superior stability due to the Z scheme operation significantly enhance its potential for practical implementations in photocatalysis and hydrogen production.

Recent advances in photocatalytic degradation of persistent organic pollutants: Mechanisms, challenges, and modification strategies

Ecosystems and human health are seriously threatened by persistent organic pollutants (POPs), which are hazardous, resistant to environmental degradation, and have the capability of bioaccumulating. The sources, ecological dispersion, and potential adverse impacts of POPs are investigated in this study, which further highlights the urgent need to develop successful remediation technologies. As it can use light energy to promote degradation, photocatalysis is a promising approach among other methods. The review explores many evolved photocatalyst materials, such as those based on nanomaterials, metal-organic frameworks (MOFs), carbon, and hybrids, highlighting their characteristics and functions in the removal of pollutants. Enhancing photocatalytic performance through modification techniques such as surface changes, doping, and co-catalyst insertion is explored. The focus is on the degrading mechanisms specific to POPs and further examines the basic ideas and processes of photocatalysis. Despite its enormous significance, environmental stability, electron-hole pair recombination, and limited light absorption are some of the obstacles that photocatalysis faces. Finally, this analysis calls for novel materials and optimization techniques to overcome existing constraints and enhance the effectiveness of POP removal, highlighting future directions for photocatalyst research.

Tailored copper doped indium sulfide nanostructures as electrode material for supercapacitor and nano photocatalyst for dye degradation

The unique copper-doped indium sulfide nanocrystals are synthesized by a gentle hydrothermal process. XRD, FTIR, XPS, FESEM/EDX, UV-DRS, and PL were used to characterize the final samples. Copper-doped indium sulfide nanostructures can be exploited as an active catalyst in photodegradation and as an electroactive material in supercapacitors due to their distinctive architecture. The copper-doped indium sulfide catalyst exhibits 85 percent photodegradation using methylene blue dye under natural sunlight irradiation, and the electrochemical test showed a capacitance of 668 Fg−1 at 1 Ag−1 in a 2 M KOH electrolyte solution. For future generations, photocatalyst and electrode can function as more desirable materials.

Influence of morphological variations in cobalt bismuth oxide on supercapacitor performance

In this study, we successfully synthesized novel cobalt bismuth oxide (CBO) using various solvothermal methods. These materials were then utilized as active electrode materials for supercapacitors and photocatalysts. A variety of techniques was employed to analyse the crystal structure, morphology, and surface of the prepared samples. The morphological analysis revealed that S1 (nanosheet) and S3 (nanoneedles) are in nanostructure form. The S3 electrode demonstrated a specific capacitance of 270.9 F g-1 at a current density of 1 Ag-1, compared to the S1 electrode, which exhibited a specific capacitance of 181.7 F g-1 under the same conditions. Furthermore, when subjected to a current density of 3 A g-1, the S1 and S3 retained 79 % and 62 % of their capacitance, respectively after 2000 cycles. The morphological variations in the samples play a crucial role in capacitive performance and mechanism, characterised by a significant presence of lattice defects and oxygen vacancies.

Synthesis of Heteromorphic Bi2WO6 Films With an Interpenetrate 1D/2D Network Structure for Efficient and Stable Photocatalytic Degradation of VOCs.

2D layered Bi2WO6 (BWO) is a widely used attractive photocatalyst for degrading VOCs, but the low visible-light utilization and the easy stacking 2D nanosheets(NSs) limit photocatalysis efficiency and stability. Here, inspired by Eucalyptus, a synergistic strategy of multiscale domain-confinement and electrostatic force action, based on electrospinning is proposed, for fabricating a heteromorphic BWO photocatalyst. It is found that BWO NSs can grow radially in an orderly spaced arrangement along BWO nanofibers (NFs) during sintering, thereby forming 1D/2D BWO junctions like eucalyptus leaves. This interpenetrating 1D/2D network structure not only solves the easy stacking problem of BWO NSs but also selectively exposes the {010} crystal planes that exhibit efficient hole oxidation. In addition, this peculiar structure enriches electrons at the 1D/2D interface to avoid carrier recombination, thus improving the photocatalytic activity. The photocatalyst material with a reduced bandgap width from 2.56 to 2.49eV can rapidly degrade 100% of acetaldehyde under visible light without using sacrificial agents and photosensitizers and shows superior stability for eight cycles without any decay. This study provides a feasible method to synthesize an efficient and stable BWO photocatalyst.

Constructing AlOOH-PVA/ZIF-67/AgCl/Ag composite membrane for the efficient photodegradation of organic pollutants under visible light irradiation

This study effectively fabricated photocatalytic membranes (∼5 cm diameter) assembled by γ-AlOOH-PVA (BOP) decorated heterostructural ZIF-67/AgCl/Ag composites by combing seeded secondary growth and photoreduction methods. First, the ZIF-67-seeded BOP membrane was shaped in a petri dish, followed by submerging in a 2-methylimidazole ligand for secondary growth to obtain the BOP/ZIF-67 membrane. Next, AgCl/Ag was formulated on the membrane by dipping it in an AgNO3 solution, followed by a photoreduction under visible LED light, resulting in a BOP/ZIF/AgCl/Ag membrane. The characterization showed that the membrane contained heterostructures of ZIF-67/AgCl/Ag anchored onto the BOP membrane. The BOP/ZIF/AgCl/Ag composite membranes exhibited enhanced light absorption and appeared the localized surface plasmon resonance (LSPR) of Ag0, giving it a bandgap energy of ∼2.10 eV. Photodegradation under visible LED light irradiation showed that the BOP/ZIF/AgCl/Ag membrane efficiently removed tetracycline (TC) and Rhodamine B dye (RhB) with corresponding degradation efficiency of ∼99% (90 min) and ∼95% (140 min), giving reaction rates of ∼0.046 min−1 and 0.019 min−1, respectively. The photocatalytic mechanism and photodegradation pathways analyses provided insights into the degradations of organic pollutants. Significantly, the designed BOP/ZIF/AgCl/Ag membrane quickly recovered from the solution and was of good durability. The study provided an effective strategy for constructing heterostructural ZIF-67/AgCl/Ag composite membranes, which are efficient and eco-friendly photocatalyst materials.

In Situ Construction of SnS2@SnO2 Heterostructure for Photo-Assisted Electrocatalysis of Oxygen Evolution Reaction.

Photo-assisted electrocatalysis has arisen as a promising approach for hydrogen generation by incorporating photocatalysts into electrocatalysts. 2D SnS2 is a photocatalyst that absorbs visible light. However, the rapid recombination of photo-generated electron-hole pairs significantly reduces the overall photocatalytic efficiency of SnS2, limiting its practical application. Thus, this study prepares an in situ heterojunction SnS2@SnO2 using a one-step hydrothermal method. The degradation efficiency of methyl orange (MO) using SnS2@SnO2 is measured, achieving a degradation rate of 92.75% within 1h, which is 1.9 times higher than that of pure SnS2. Additionally, FeNiS/SnS2@SnO2 is synthesized and exhibited significant improvements in the photo-assisted oxygen evolution reaction (OER). It achieves an overpotential of 260mV and a Tafel slope of 65.1mVdec-1 at 10mAcm-2, showing reductions of 11.8% and 31.8%, respectively, compared to FeNiS alone. These enhancements highlight the strong photo-response capability of SnS2@SnO2. Under the internal electric field of SnS2@SnO2, the photogenerated electrons in the conduction band of SnS2 quickly move toward SnO2, facilitating efficient photocatalytic reactions. FeNiS, with a lower Fermi energy level (EF), facilitates electron transfer from SnS2@SnO2 and enhances OER performance by efficiently participating in the reaction. This study paves a new path for 2D photocatalyst materials.

Investigation of methylene blue dye degradation using green synthesized mesoporous silver-titanium

In this study, we synthesized mesoporous silver-titanium (Ag/TiO2) through green synthesis approach using mangosteen pericarp extract, which subsequently can act as both adsorbent and photocatalyst materials. Additionally, we investigated and compared the degradation of methylene blue (MB) using mesoporous Ag/TiO2 under dark conditions, visible light irradiation, and both dark-light conditions to analyze the adsorption-photocatalysis activity. The achieved mesoporous structure in this study offers distinct advantages as an adsorbent. Moreover, the addition of silver (Ag) to titanium dioxide (TiO2) shows promise in enhancing photocatalytic activity in MB degradation, which enhances photocatalytic activity in the visible light region due to its localized surface plasmon resonance (LSPR), which excites more electrons, resulting in increased MB degradation. The highest degradation percentage of 97.08 % was obtained using a dark-light degradation mechanism, demonstrating that the synthesized mesoporous Ag/TiO2 has potential as an effective integrated adsorbent-photocatalyst material for MB dye degradation.

Enhancing degradation of novel brominated flame retardants by sulfate modified C3N4: Synergistic effect of photocatalytic oxidation and reduction processes

Novel brominated flame retardants (NBFRs) pose serious risks to aquatic organisms and human health due to their persistence and toxicity. Herein, sulfate ions (SO42-) decorated C3N4 (SO42-@CN) photocatalyst material was synthesized for the rapid degradation of NBFRs by a synergistic effect of photocatalytic oxidation and reduction reactions. Compared with bare C3N4, the SO42-@CN exhibited efficient photocatalytic NBFRs removal performance. The degradation rates constant of hexabromobenzene and pentabromotoluene by SO42-@CN were 0.177 and 0.0906 min-1, respectively, which were 2.9 and 6.7 times higher than that by C3N4. It was confirmed that SO42-@CN could generate more active substances (such as sulfate radicals, and hydroxyl radicals) and promote the oxidation of NBFRs. Meanwhile, SO42- accelerated the separation of photogenerated electron-holes by promoting the formation of hydrogenated structures, allowing more photogenerated electrons to participate in the debromination reduction process. This work provides a new insight for the practical application of visible light driven photocatalytic technology in NBFRs residues degradation.

A vertically staged 2D van der Waals SnS2/SiS2 heterostructures for photovoltaic and photocatalytic application

This study investigates into the geometric, optical, and thermodynamic characteristics of the vertically staged 2D van der Waals SnS2/SiS2 heterostructure, examining its potential for photovoltaic and photocatalytic applications. A study of the band alignment reveals an indirect band-gap p-type semiconductor with a z-scheme configuration. The density of states highlights the significant influence of S-4p orbitals on the valence band near the Fermi level, while Sn/Si-3p orbitals contribute to the conduction band minimum. Furthermore, the SnS2/SiS2 heterostructure can control interlayer charge transport, impacting the band gap. Notably, the lower work function of the SnS2 layer facilitates the spontaneous migration of electrons from SnS2 to SiS2 within the heterostructure. These results, coupled with reduced work function and enhanced optical properties, emphasize the potential of this heterostructure as an efficient photocatalyst and photovoltaic material.

THE EFFECT OF NACL ADDITION TO TiO2/NiSe/NC PHOTOCATALYTIC FOR HYDROGEN GAS PRODUCTION

The widespread utilization of fossil fuel has resulted in fuel scarcity due to population growth and increased industrialization, driving the evolution of new renewable energy sources (NRE). Alternatively, hydrogen production through solar water splitting and TiO2 as a potential photocatalyst can be developed due to its good stability, environmental friendliness, and economic viability. However, TiO2 has the disadvantage of a wide bandgap that requires high energy and fast recombination. Therefore, in this research, TiO2/NiSe (TN) was synthesized with N doped carbon dopant modified with NaCl as a photocatalyst material through a solvothermal method. The characterized material using XRD, SEM, UV-DRS, BET, and FTIR. Photocatalytic activity tests were conducted to determine hydrogen production using an MQ8 sensor integrated with an Arduino microcontroller system. The synthesized materials are TN, TNC-0, and TNC-10. The addition of NaCl in carbon doped nitrogen materials of photocatalyst TNC-10 shows a reduction of the bandgap that is the lowest bandgap value obtained was 3.09eV. The photocatalytic activity test results showed a hydrogen production of 120 ppm for TNC-10, which is six-times higher compared to bare TiO2 as a photocatalyst. The increase in hydrogen gas production is due to the addition of NaCl to NC, which can enhance the photocatalytic activity and hydrogen adsorption on the catalyst surface during hydrogen production.

Photodegradation of Methylene Blue Dye Using BiVO₄/g-C₃N₄ Composites under Visible Light Irradiation

This study evaluates the degradation of methylene blue through photocatalysis using BiVO4/g-C3N4 material with the help of visible light. Material characterization was conducted using X-ray diffraction, scanning electron microscopy, and UV-Vis diffuse reflectance spectroscopy data. The characterization results show that the crystal structure of BiVO4/g-C3N4 is a heterojunction between monoclinic BiVO4 and hexagonal g-C3N4, with a crystal size of about 10.16 nm and a band gap energy value of about 2.16 eV. The morphology formed is a combination of sheet and rod-like. This study optimized the photocatalytic activity of the composite by analyzing the variation of g-C3N4 concentration, degradation time, and methylene blue pH. The results show that the BiVO4/g-C3N4 sample has optimal photocatalytic and adsorption properties in sample B (1:3) with pH 7 and a degradation time of 150 minutes. Under these conditions, the BiVO4/g-C3N4 composite successfully degraded methylene blue by 94.14%. The rate kinetics of the photocatalytic reaction followed first order, with *OH species playing the most role in the degradation mechanism. These findings highlight the potential of BiVO4/g-C3N4 as an effective photocatalyst material for organic pollutant degradation applications, offering a sustainable solution for wastewater treatment.

C/N/CeO2/Alpha-Fe2O3 Doped Mesoporous Carbon as A Photocatalyst Material for Hydrogen Gas Production by Water Splitting Method

This study focuses on hydrogen production through a water-splitting photocatalytic reaction using solar energy and an additional semiconductor material C/N/CeO2/α-Fe2O3 as a photocatalyst. The semiconductor material C/N/CeO2/α-Fe2O3 underwent thorough characterization via FTIR, FESEM-EDX, XRD, N2 adsorption-desorption, and UV-Vis-DRS analysis. Subsequently, photocatalytic activity tests were conducted to measure hydrogen production levels for varying weight percentages of C/N/CeO2/α-Fe2O3, including 0%, 10%, and 15 mass% of the C/N component. Results showed that the material with 0% variation produced 2.21 μmol/gram of hydrogen gas (1 hour) and 17.58 μmol/gram (after 3 hours), while the 10% variation yielded 4.52 μmol/gram (1 hour) and 19.08 μmol/gram (after 3 hours). These findings suggest that the C/N/CeO2/α-Fe2O3 material containing 10% C/N may offer the most optimal performance as a photocatalyst for hydrogen production.

Inorganic/organic hybrid interfacial internal electric field modulated charge separation of resorcinol-formaldehyde resin for boosting photocatalytic H2O2 production

The strategy of inorganic/organic semiconductor material hybridization is of great significance for the development of highly active photocatalysts. Resorcinol-formaldehyde (RF) resin with a special donor-acceptor (D-A) structure shows excellent performance in the photocatalytic production of H2O2. However, the lack of an internal driving force for the separation and transfer of photogenerated electrons and holes in RF resin greatly limits the performance of H2O2 production. Herein, an inorganic/organic hybrid core-shell structure ZnS@RF photocatalyst was prepared by directionally induced coating of RF resin shells of different thicknesses on the surface of monodisperse ZnS nanospheres. Consequently, the photocatalytic H2O2 performance of ZnS@RF with the optimal RF resin shell thickness reaches 367.9 μmol L−1, which is 69 and 2 times that of ZnS and HRF, respectively. Density functional theory (DFT) calculations and related characterization results collectively demonstrate that the excellent photocatalytic H2O2 production performance of ZnS@RF photocatalyst is mainly attributed to the internal electric field (IEF) formed at the hybrid interface of ZnS and RF heterojunction and the optimization of RF shell thickness, which significantly enhances the separation and transfer of photogenerated carriers and modulates the interfacial catalytic reaction kinetics. This work opens up an avenue for designing inorganic/organic hybrid heterojunction photocatalyst materials with excellent photocatalytic activity.

(Invited) Charge Separation and Stabilisation in Photocatalyst Materials for Solar Driven Water Splitting

In photocatalytic systems for solar energy conversion, a key challenge for efficient operation is the efficient separation and stabilisation of photogenerated charges, and thereby the minimisation of undesired recombination losses. This challenge is particularly great for photocatalytic systems because of the long charge lifetimes required to drive catalysis A further consideration is to minimise the energy losses required to drive this charge separation. My talk will cover examples of recent work from my group addressing aspects of this challenge. I will start by considering the role of polaron localisation / relaxation in driving charge separation in metal oxides, and quantification of the energetic loss associated with this polaron formation. Kinetic competion between polaron formation and ligand field state mediated charge recombination will be highlighted as the key challenge limiting the performance of many visible light absorbing metal oxides. The roles of metal oxide dielectric constant, surface facet energies, traps, ‘photocharging’ and heterojunctions in aiding charge separation in metal oxides will be discussed, drawing on examples from BiVO4 and SrTiO3. I will then go on to discuss charge separation and stabilisation in alternative photocatalyst materials, including organic semiconductor nanoparticles and metal-organic frameworks, highlighting the observation of remarkably long lived charge photogeneration in both systems and their relevance to the efficiency photocatalytic performance.