Selective Photocatalytic Oxidation Research Articles

In Situ Preparation of Highly Active and Selective Fe‐MOF/V–C3N4 for Photocatalytic Hydroxylation of Benzene to Phenol

AbstractThe selective photocatalytic oxidation of benzene to phenol under mild conditions is of great significance for the next‐generation phenol industry. In order to improve the efficiency of the phenol production process, a heterojunction catalyst based on Fe‐MOF/V–C3N4 was synthesized by solvothermal method. Compared with Fe‐MOF and C3N4, the photogenerated charge separation rate of this composite catalyst was significantly enhanced, and the photogenerated electron‐hole complexation was significantly weakened.Under the optimal conditions, the yield and selectivity of phenol were 18.75 % and 96 % respectively, and the photocatalytic activity remained high after four reaction cycles. The improved strategy for this catalyst will provide some new insights for the development of more efficient photocatalysts for the direct hydroxylation of benzene to phenol.

Efficient and selective photocatalytic oxidation of benzylic alcohols with built-in electric field CsPbBr3/SiO2 nanocomposites through Fe3+ gradient doping

Lead halide perovskite nanocrystals (PNCs) have emerged as promising materials for photocatalysis due to their exceptional optoelectronic properties, yet achieving efficient charge separation and selective oxidation reactions remains a significant challenge. In this study, we report the synthesis of Fe3+-doped CsPbBr3/SiO2 nanocomposites (Fe-PNCs/SNPs) with gradient energy levels, designed to enhance photocatalytic performance. Our results demonstrate that Fe3+ doping introduces mid-gap states, promotes photoinduced charge separation, and generates reactive oxygen species (ROS) such as O2− and OH radicals under sunlight-simulating light irradiation from a 300 W Xe arc lamp. The Fe20-PNCs/SNPs catalyst achieved over 99 % conversion of benzyl alcohol to benzaldehyde with high selectivity and stability in the ethanol under ambient conditions. Additionally, the catalyst exhibited excellent recyclability and broad substrate tolerance. These findings highlight the innovative design of gradient energy levels in perovskite nanocomposites, offering a new strategy for enhancing photocatalytic efficiency in selective organic transformations.

0D/1D p-n heterostructured composite of bismuth ferrite perovskite clusters on sodium titanate nanotube arouse exceptional blue-light-driven photooxidation

This study describes the synthesis of a 0D/1D p-n heterostructured composite of bismuth ferrite perovskite clusters on sodium titanate nanotubes prepared using an in-situ hydrothermal method. BiFeO3/Na2Ti3O7 (BFT) nanocomposite, forming a p-n heterojunction due to the equilibrium of Fermi level, exhibits exceptional blue-light-driven photo-oxidation activity with an exceptional benzyl alcohol conversion rate of 29.64 mmolproduced BAD·g−1 h−1. The outstanding performance originates from the promotion of photogenerated charge separation and effective inhibition of charge recombination due to internal electric field of p-n heterojunction. Density functional theory calculations combined with femtosecond transient absorption spectroscopy distinctly confirms the efficient separation and transfer of photogenerated carriers to be S-scheme charge transfer mechanism over the p-n heterojunctions. Furthermore, in-situ infrared spectroscopy combined with XPS results demonstrate the strong adsorption of benzyl alcohol and weak adsorption of benzaldehyde on BFT, which facilitates the transformation of reactant and desorption of product. This study provides a simple and effective approach to enhance photocatalytic selective oxidation reactions.

Efficient charge abstraction and oriented accumulation driven by strong interfacial interaction facilitate photocatalytic selective oxidation of furfuralcohol coupled with H2 evolution

S-scheme heterostructures are promising strategies for photogenerated charge transport and spatial separation, yet the intrinsic mechanism of interfacial interaction on carrier dynamics remains under exploration. Herein, an S-scheme NiTiO3/Cd0.6Zn0.4S (NTO/CZS) heterostructure with strong interfacial interaction was fabricated to synchronously drive redox half-reactions. The KPFM, SPV, in-situ ESR, in-situ XPS, and fs-TA combined with and DFT simulation confirmed the reinforced IEF’s role in efficient charge abstraction and oriented accumulation on RP and OP surfaces, respectively, thereby synchronously triggering redox half-reactions. In addition, the furfuryl alcohol (FOL) to furfural (FAL) conversion was driven by αC-H bond cleavage, with H2O playing a crucial role in achieving efficient photocatalytic selective oxidation of FOL coupled with H2 evolution reaction (HER). The optimized 35 % NTO/CZS exhibited exceptional photocatalytic performance, achieving FOL selective oxidation coupled with HER, surpassing that of CZS and NTO for HER of 3.3 mmol g−1 h−1 by 6 times and 50 times, respectively. The present work provides new insights into constructing S-scheme heterostructures with strong interfacial electric field (IEF) for efficient charge abstraction and oriented accumulation to synchronously facilitate redox half-reactions.

Highly selective photocatalytic oxidation of CH4 to CH3OH: A theoretical study

Photooxidation of methane (CH4) in aqueous solution to generate high-value organic compounds is an effective way to replace traditional industrial methods. It is crucial to select catalysts that can avoid competitive reactions and achieve high selectivity. Using first principles calculations, a novel one-dimensional (1D) Ti3C2O2 nanoribbon (NR)/two-dimensional (2D) monolayer MoS2 (MS) heterojunction photocatalyst was ingenious designed in this work, which can achieve the oxidation of CH4 molecules and suppress the execution of competitive reactions. The results indicate that the constructed 1D NR exhibits semiconductor properties and its energy level position meet the requirements of photocatalytic oxidation for CH4. The heterojunction structure composed of NR and MS forms an efficient S-Scheme electron transfer mechanism under illumination, which not only provides sufficient internal driving force for CH4 oxidation, but also effectively avoids the competitive reaction between water molecules and photo-generated holes. Specifically, the photocatalysts exhibits high selectivity and low reaction overpotential for the generation of methanol (CH3OH). This study provides a new perspective for photocatalytic CH4 oxidation and demonstrates the potential application value of 1D MXene in the future field of photocatalysis.

Linker Modulation of Covalent Organic Frameworks at Atomic Level for Enhanced and Selective Photocatalytic Oxidation of Thioether

Linker Modulation of Covalent Organic Frameworks at Atomic Level for Enhanced and Selective Photocatalytic Oxidation of Thioether

Enhanced selective photocatalytic reduction and oxidation of perfluorooctanoic acid on Bi/Bi5O7I decorated with poly (triazine imide)

Perfluorooctanoic acid (PFOA) is detected widely in surface and groundwater globally. Its removal poses a significant challenge due to its high chemical stability. This study demonstrates efficient PFOA degradation using poly-triazine-imides-tailored defective Bi5O7I (PTI/BB). Under 300W Xe irradiation, 1µg·L-1 PFOA could be degraded to 9.86ng·L-1 after 3hours in the presence of 0.5g·L-1 25% PTI/BB. The mechanism investigation reveals that the oxygen vacancy (OV) in partially reduced Bi/Bi5O7I (BB) generates impurity states, enhancing the light-harvesting capacity. Furthermore, forming a type Ⅱ heterojunction between conjugated PTI and BB facilitates the efficient separation of photogenerated carriers. The resulting photogenerated electrons (reduction) and holes (oxidation) drive hydrogenation reduction and oxidative decarboxylation of PFOA, respectively. This synergistic effect consequently achieves significant defluorination of PFOA. The proposed PFOA degradation pathway via the PTI/BB catalyst offers new insights into the catalyst design for photocatalytic degradation of per- and polyfluoroalkyl substances (PFAS).

Cyanobacterial hydrothermal carbonization carbon as photocatalyst for selective aerobic oxidation of cyclohexane

The exploration of catalyst preparation techniques that incorporate environmental-friendly methodologies has consistently been the focus of scientific inquiry within the field of green synthesis of oxygen-containing organic chemicals. Herein, a metal-free hydrothermal carbonation carbon (HTCC) has been prepared utilizing cyanobacterial biomass produced during a water bloom in a freshwater lake. The HTCC produced is capable of performing photocatalytic selective oxidation of cyclohexane to cyclohexanol and cyclohexanone (KA oil) under ambient conditions. The use of cyanobacterial biomass allows for the efficient preparation of HTCC, which exhibits a conversion rate of cyclohexane that is 4.1 times of HTCC prepared with alternative carbon sources (glucose). The selectivity to KA oil over the samples are almost 100%. Characterizations and analysis reveal that cyanobacteria can lead to self-doping of nitrogen and hydrophobicity of the resulting HTCC, while sulfuric acid etching endow it with more photoactive sp2 hybridized structure units that contribute to a higher photogenerated carrier separation efficiency. The suitable band structure enables the cyanobacterial HTCC to produce superoxide radicals to oxidize cyclohexane. These findings are of great significance for the development of eco-friendly photocatalysts and the utilization of biomass resources.

Surfactants govern the fabrication of sulfur-enriched heterojunction catalysts for highly selective photocatalytic conversion of toluene

Photocatalytic selective oxidation of toluene represents a milder and more environmentally friendly strategy for the synthesis of benzaldehyde. In order to enhance catalytic performance, efficient carrier separation and transport are crucial in the photocatalytic process. This study focused on the preparation of ZnS@ZnIn2S4 with sulfur vacancies and heterostructures, combining the advantages properties of ZnS and ZnIn2S4 in photocatalysis. The effects of ZnS and surfactants on the catalytic properties of the composites were studied in depth. Characterization tests revealed that surfactant-modified ZnS@ZnIn2S4 exhibited a higher concentration of sulfur defects, which facilitated electron trapping and promoted photogenerated carrier separation and utilization. Additionally, the present study also demonstrated that the incorporation of ZnS and surfactants could reduce the crystal size of ZnIn2S4, thereby facilitating the exposure of additional active sites. The synergistic effect of the aforementioned advantages enabled toluene to undergo oxidation at a conversion rate of 39% in the presence of oxygen, resulting in the production of benzaldehyde with an exceptional selectivity of 92%. This finding offers valuable insights for future endeavors in designing photocatalytic C-H bond oxidation catalysts.

Construction of g-C3N4-based donor-acceptor conjugated copolymer for photocatalytic selective oxidation of biomass-derived 5-hydroxymethylfurfural under visible light

Donor-acceptor structure porous nanosheets CNSA-x (x denotes the amount of salicylic acid) were prepared by co-thermal condensation polymerization of aromatic compound salicylic acid (SA) and prepolymer melamine. A variety of characterization methods have been used to thoroughly analyze the morphology, structure, optical and electrical features of the synthesized catalysts. It turned out that the introduction of SA promotes the formation of pore structure and an enhanced specific surface area, which resulted in more reactive sites. Moreover, the introduction of SA improves light absorption capacity and effectively adjusts the valence band position. Meanwhile, it also extends the delocalization system, thereby promoting the migration and separation of photogenerated electron-hole pairs. The catalyst exhibited high performance and stability in the photocatalytic oxidation of 5-hydroxymethylfurfural (HMF) under the synergies of these advantages. Additionally, the elucidation of active reaction species and proposed reaction mechanism enriched the understanding of the catalytic process.

Selective Photocatalytic Oxidation of 5‐Hydroxymethylfurfural using Ce doped TiO2: A Crucial Role of Defective Sites

AbstractTransforming platform compounds with conventional catalysts, such as homogeneous and heterogeneous, into valuable chemicals encounters challenges associated with entailing high temperature/pressure and reusability during the reaction. To address these challenges, photocatalysis is one of the promising approaches, especially with visible‐light‐driven photocatalysts for selective transformation. A series of cerium‐doped TiO2 (CexTiO2; x=0.5, 1, 3 and 5 wt %) are prepared via a simple coprecipitation method for the cocatalyst‐free selective oxidation of 5‐hydroxymethylfurfural (HMF) to 2,5‐diformylfuran (DFF) under visible light illumination. Introducing Ce into the network to TiO2 generates impurity energy levels, reduces the band gap, and extends the spectral response range. This also causes slight distortion to the surface structure, thereby originating defective sites and various surface oxygen species, confirmed by X‐ray photoelectron spectroscopy and electron paramagnetic resonance studies. The HMF adsorption studies infer that HMF forms a surface complex with CeTiO2, facilitating the formation of ligand‐to‐metal charge transfer complex (LMCT) under visible light (~420 nm), which efficiently catalyzes the conversion of HMF (54.4 %) to DFF with a selectivity of >99 %. In‐situ DRIFTS and surface passivation studies provide insight into the interaction between HMF and surface acidic/basic sites along with hydroxyl groups of CeTiO2, which subsequently convert selectively to DFF.

Photocatalytic Selective Oxidation of Toluene over Chlorine-Coordinated MIL-101(Fe) under Ambient Conditions.

The activation of an inert C(sp3)-H bond in selective oxidation of hydrocarbons under mild conditions is a critical and challenging process. Herein, we report a stable chlorine-coordinated metal-organic framework (MOF) photocatalyst, MIL-101(Fe), for efficient visible-light-driven photocatalytic selective oxidation of toluene to benzaldehyde in air under ambient conditions. Encouragingly, a benzaldehyde formation yield of 3.11 mmol·g-1·h-1 with a selectivity of 92.1% is achieved in 5 h, which is superior to most of the reported works. Based on the experimental results and characterizations, the high catalytic performance is mainly due to the promoted rate-limiting step of C(sp3)-H bond activation by a chlorine radical (Cl·) from the coordinated -Cl in the MIL-101(Fe) structure. In addition, the present photocatalyst possesses good substrate tolerance for photocatalytic selective oxidation of various toluene derivatives under optimized conditions.

Hydrothermal synthesis of bare TiO2 nanowires and polystyrene (PS)-TiO2 nanowires used for selective photocatalytic oxidation of 3-pyridinemethanol in water and PS photodegradation in solid state

In the present work, nanowire (NW) structured TiO2 nanoparticles were prepared using the hydrothermal method and characterized by X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), and BET specific surface area techniques. They were obtained in the anatase phase and presented a high surface area (ca. 300 m2/g). A commercial TiO2 (anatase, Merck) was used for comparison. The TiO2 catalysts were tested for photocatalytic oxidation of 3-pyridinemethanol to 3-pyridinemethanal and vitamin B3 in water under UVA irradiation. The effects of acid treatment and subsequent calcination for TiO2 catalysts after the hydrothermal synthesis were also investigated. The sample, subjected to acid treatment and calcined at 300 °C (NW-HCl-300), showed the highest photocatalytic activity and selectivity towards the products. Consequently, this sample and Merck TiO2 were used to prepare polystyrene (PS)/TiO2 composites using the hydrothermal method. They were characterized by XRD, SEM–EDX, Nuclear Magnetic Resonance (NMR), Fourier Transform Infrared Spectroscopy (FT-IR), Thermogravimetric analysis (TGA), Differential Scanning Calorimetry (DSC), UV–Vis, Gel Permeation Chromatography (GPC), and contact angle measurements and tested for PS (present in the composite) photodegradation. The results indicated that NW-HCl-300 had a high surface area, and was highly hydroxylated, favouring a good distribution of PS in the composite. The composite presented high thermal stability, but under UVA irradiation the polymer underwent solid-state photocatalytic degradation due to the contact with TiO2. The composite photodegradation was investigated using gravimetric, GPC, FT-IR, UV–Vis, and SEM techniques.

Ultrafast Charge Transfer in a Core-shell CdS@Cu-TCPP-Pt Heterojunction for Photocatalytic Hydrogen Production Coupled with Selective Benzylamine Oxidation.

Photocatalytic selective oxidation of organic substances coupled with hydrogen production is believed to be one of the most favorable pathways to make full use of photogenerated charge carriers. However, this catalytic reaction is often discouraged due to the rapid recombination of photogenerated carriers in practical applications. In this work, a core-shell CdS@Cu-TCPP-Pt nanorod heterojunction was dexterously designed for boosting the photocatalytic dehydrogenation performance of benzylamine. The transient absorption results revealed that the photogenerated electron-holes could be effectively separated by properly matching the energy levels in CdS@Cu-TCPP. Surprisingly, Pt embedded in Cu-TCPP not only provided abundant hydrogen production active sites but also facilitated ultrafast charge transfer, which endowed CdS@Cu-TCPP-Pt with remarkable photocatalytic performances for the coproductions of N-benzylidenebenzylamine (1 mL) with a conversion of 23.48% and H2 (20.75 mmol g-1 h-1) under visible irradiation, far surpassing those of CdS and Cu-TCPP. Obviously, the present work verifies that designing and fabricating a hybrid photocatalyst with high separation efficiency of electron-hole pairs is also a significant avenue for other high-performance cooperative dual-functional photocatalytic reactions.

Efficient hole extraction to reactive oxidation sites over a Co3O4/Cs3Sb2Br9 p-n heterojunction for enhanced benzylic C(sp3)-H bond oxidation

Photocatalytic selective oxidation of aromatic hydrocarbons plays an important role in the production of value-added chemicals. A key step in this process is the activation of C(sp3)-H bond by photogenerated holes. However, the inadequate hole generation and lack of surface adsorption-activation sites severely hinders the improvement in photocatalytic C-H bond oxidation. In particular, the random charge migration to the surface impedes the effective capture of holes by surface active sites to dissociate the C(sp3)-H bond. Here, we design and fabricate a Co3O4/Cs3Sb2Br9 p-n heterojunction that effectively addresses these challenges. The p-n heterojunction forms strong built-in electric fields (BEF) facilitating spatial charge separation. Holes are accumulated on Co3O4, while electrons are accumulated on Cs3Sb2Br9, thereby offering abundant active holes and electrons. Moreover, Co3O4 shows stronger adsorption and activation capacity for the C(sp³)-H bond, enabling the C(sp3)-H bond dissociation with low reaction energy barrier. Consequently, the holes are directionally extracted from photoactive Cs3Sb2Br9 to catalytically active Co3O4 under visible light irradiation, thereby accelerating the toluene oxidation. The optimized 5 % Co3O4/Cs3Sb2Br9 exhibits a benzyl aldehyde (BAD) evolution rate of 5044 μmol g−1 h−1 and a benzyl alcohol (BA) production rate of 1820 μmol g−1 h−1, which are 12 and 17 times higher than that of blank Cs3Sb2Br9, respectively.

1O2‐Mediated Selective Oxidation of 5‐hydroxymethylfurfural to 2,5‐diformylfuran by Ag/Ag3PO4 under Visible Light Irradiation

AbstractThe synthesis of 2,5‐diformylfuran (DFF) through photocatalytic oxidation of 5‐hydroxymethylfurfural (HMF) is an attractive approach. In this manuscript, a photocatalytic selective oxidation strategy for HMF was developed, using Ag/Ag3PO4 as the photocatalyst and O2 as the oxidizing agent. The prepared catalyst was characterized systematically by SEM, XRD, XPS, UV‐Vis, PL spectra, and so on. In contrast to previous photocatalytic oxidation strategies for HMF conversion, this catalytic system could efficiently generate 1O2 without other reactive oxygen species (ROS) under visible light irradiation. DFF would be obtained with about 90 % selectivity. Moreover, the exclusive formation of 1O2 was linked to the more positive conduction band potential (+0.90 eV) of Ag/Ag3PO4, confirmed by an array of characterization techniques. Additionally, the stability of the catalyst was assessed through cyclic testing and analyses including XRD, and XPS. Nonetheless, this catalytic system could potentially serve as a robust platform for various selective oxidation reactions in the future, due to its exclusive presence of 1O2 without the involvement of other ROS.

Gold supported on Bi2MoO6 based on oxygen vacancy structure: Enhanced adsorption activation for efficient photocatalytic selective oxidation of benzyl alcohol

In this work, ethylene glycol was used as a mild reducing agent to prepare Bi2MoO6 support with oxygen vacancies. By introducing Au active species, an Au/BMO-Ov (Bi2MoO6 support with oxygen vacancies) photocatalyst was synthesized, which was co-modified with oxygen vacancies and Au NPs (nanoparticles), and significantly improved the capability of Bi2MoO6 for visible light-driven BA (benzyl alcohol) conversion. The 1 wt% Au/BMO-Ov exhibited the highest conversion (98.8 %) of BA and excellent selectivity (97.4 %) of BAD (benzaldehyde) under visible light. Oxygen vacancies have an inhibitory effect on the recombination of photogenerated carriers. Au NPs acted as both photosensitizers (LSPR effect captures light and generates electrons and holes) and active species (used as Lewis acids). The results of photoelectrochemistry (PEC) tests confirmed that the synergistic interaction of Au and oxygen vacancies enhanced the photoactivity of bismuth molybdate. Meanwhile, density functional theory (DFT) calculations indicated that oxygen vacancies and Au synergistically reduced the bandgap energy of Bi2MoO6 and enhanced the adsorption of BA. Au served as the Lewis acid site for adsorption of BA, and improved the reactivity of light-driven BA conversion. The corresponding mechanism was proposed based on the experimental results and DFT calculations.

Selectively photocatalytic oxidation of methane to methanol promoted by Charge-Polarized Zn-Ti pairs

Photocatalysis offers an intriguing route for selective oxidation of CH4 to CH3OH under mild conditions. However, owing to the ultra-high stability of CH4 and the diversity of oxidative products, the activity of CH4 oxidation and the selectivity of CH3OH are still far from satisfactory. Herein, we report a dual-cocatalyst of Au and bimetallic oxide (Zn2Ti3O8) nanoparticles (NPs) modified TiO2 nanotube (Au/Zn2Ti3O8/TiO2) for highly active and selective photocatalytic oxidation of CH4 to CH3OH with O2 at room temperature. The introduction of Zn2Ti3O8 NPs is skillfully exploited the epitaxies of ZIF-8 on the surface of protonated titanate nanotubes (H-TNTs) and the followed thermal treatment with air. During photocatalytic CH4 oxidation, 1.7 %Au/Zn2Ti3O8/TiO2-4 achieved a formation rate of liquid oxygenates of 1200 μmol·gcat.–1·h−1 with a CH3OH selectivity of 91.5 %, which were much higher than those over 1.7 %Au/TiO2 and 1.7 %Au/ZnO. Mechanism investigation confirmed the presence of the strong electron interaction between Au NPs, Zn2Ti3O8 NPs and TiO2 nanotubes in 1.7 %Au/Zn2Ti3O8/TiO2-4, which intensified the charge polarization between Zn sites and Ti sites. These charge-polarized Zn-Ti sites were not only beneficial to the adsorption and activation of CH4, but also accelerated the further transformation of CH3OOH to CH3OH, as well as inhibited the excessive oxidation of CH3OH.

Rational design of nitrogen and carbon co-decorated mesoporous TiO2 composites for photocatalytic selective oxidation of alcohols

Photocatalytic organic synthesis has attracted much attention in recent years. Herein, a N and C co-decorated mesoporous TiO2 (mp-NCT) photocatalyst was synthesized for selective oxidation of alcohols. Notably, the as-prepared mp-NCT composites possess large specific surface areas and mesoporous structures, which could provide sufficient active sites and improve mass transfer. Furthermore, the co-doping of N and C species could not only extend the light absorption, but also tune the valence band of TiO2. Meanwhile, numerous oxygen vacancies and intra-band could be introduced, which helps to reduce the combination of the photogenerated carriers. As a result, the mp-NCT composites show excellent photocatalytic performance towards selective oxidation of benzyl alcohol and its derivatives to corresponding aldehydes under simulated sunlight irradiation. Mechanism studies revealed that the photogenerated electrons, holes and high dynamic equilibrium concentration of O2•- radicals were responsible for the efficient conversion of alcohols to aldehydes.

Highly selective aerobic oxidation of cyclohexane by flower-like MoO3-x microspheres-nitrogen-doped carbon dots heterojunction

Due to the higher susceptibility of alcohols and ketones to oxidation compared to alkanes, converting inert C-H bonds in alkanes into high value-added product KA oil with high selectivity is still a significant obstacle. In this study, flower-like microspheres of MoO3-x, featuring aligned nanosheets and oxygen vacancies, were combined with nitrogen doped carbon dots (NCDs) to fabricate S-scheme heterojunctions of MoO3-x-NCDs for boosting the photocatalytic efficiency in oxidizing cyclohexane. Because of the oxygen vacancies-triggered localized surface plasmon resonance (LSPR) and the S-scheme charge transfer mechanism, there was a significant improvement in the absorption of visible light and an enhancement in the efficiency of charge separation. The MoO3-x-NCDs composites exhibited a notably improved catalytic performance in cyclohexane oxidation. The MoO3-x-NCDs composite exhibited remarkable selectivity of KA oil in catalyzing cyclohexane oxidation under light exposure, attributed to the substantial increase in cyclohexane adsorption capacity. The highest cyclohexane transformation rate of 9.98 % was achieved by MoO3-x-NCDs-2 composites with a MoO3-x/NCDs ratio of 50:1, outperforming bare MoO3-x by 1.81 times, while exhibiting a KA oil selectivity reaching 93.75 %. The mechanism of selective photocatalytic oxidation was explored using photoelectric examination, analysis of energy bands, and evaluation of active radicals. In this research, green photocatalysts were fabricated through the utilization of NCDs, enabling efficient conversion and selective oxidation of cyclohexane in gentle environments. This innovative approach holds great potential for advancing the field of photocatalysis.