Hydrogen-Doping-Induced Metal-Like Ultrahigh Free-Carrier Concentration in Metal-Oxide Material for Giant and Tunable Plasmon Resonance

The practical utilization of plasmon-based technology relies on the ability to find high-performance plasmonic materials other than noble metals. A key scientific challenge is to significantly increase the intrinsically low concentration of free carriers in metal-oxide materials. Here, a novel electron–proton co-doping strategy is developed to achieve uniform hydrogen doping in metal-oxide MoO₃ at mild conditions, which creates a metal-like ultrahigh free-carrier concentration approaching that of noble metals (10²¹ cm⁻³ in H_1.68MoO₃ versus 10²² cm⁻³ in Au/Ag). This bestows giant and tunable plasmonic resonances in the visible region to this originally semiconductive material. Using ultrafast spectroscopy characterizations and first-principle simulations, the formation of a quasi-metallic energy band structure that leads to long-lived and strong plasmonic field is revealed. As verified by the surface-enhanced Raman spectra (SERS) of rhodamine 6G molecules on H_xMoO₃, the SERS enhancement factor reaches as high as 1.1 × 10⁷ with a detection limit at concentration as low as 1 × 10⁻⁹ mol L⁻¹, representing the best among the hitherto reported non-metal systems. The findings not only provide a set of metal-like semiconductor materials with merits of low cost, tunable electronic structure, and plasmonic resonance, but also a general strategy to induce tunable ultrahigh free-carrier concentration in non-metal systems.     

Ultrathin Molybdenum Dioxide Nanosheets as Uniform and Reusable Surface‐Enhanced Raman Spectroscopy Substrates with High Sensitivity

Metal oxides have advantages over the traditional noble metals to be used as substrate materials for surface‐enhanced Raman spectroscopy (SERS) with low cost, versatility, and biocompatibility, but their enhancement factors are generally quite low with a poor limit of detection. Here, ultrathin molybdenum dioxide (MoO₂) nanosheets synthesized by chemical vapor deposition demonstrated in large area are used as SERS substrates with superior signal uniformity in the whole area with a limit of detectable concentration down to 4 × 10^?8m and enhancement factor up to 2.1 × 10⁵, exceeding that of 2D materials and comparable to that of noble metal films. More practically important, the planar MoO₂ substrate is more robust than noble metals and shows excellent reusability and uniformity, which is usually prohibited for nanostructured or nanoparticle‐based metal oxide substrates. The enhancement is mainly attributed to the surface plasmon resonance effect as evidenced by the first principle calculations and UV–vis absorption spectroscopy characterization, which can be further increased by decreasing the thickness of the MoO₂ nanosheets. The overall superior performance makes the MoO₂ nanosheets an ideal substrate for practical SERS applications.     

Atomic Modulation Triggering Improved Performance of MoO3 Nanobelts for Fiber‐Shaped Supercapacitors

Asymmetric supercapacitors (ASCs) are emerging as a new class of energy storage devices that could potentially meet the increasing power and energy demand for next‐generation portable and flexible electronics. Yet, the energy density of ASC is severely limited by the low capacitance of the anode side, which commonly uses the carbon‐based nanomaterials. Here, the demonstration of sulfur‐doped MoO_3?x nanobelts (denoted as S‐MoO_3?x) as the anode for high‐performance fiber‐shaped ASC are reported. The Mo sites in MoO₃ are intentionally modulated at the atomic level through sulfur doping, where sulfur could be introduced into the MoO₆ octahedron to intrinsically tune the covalency character of bonds around Mo sites and thus boost the charge storage kinetics of S‐MoO_3?x. Moreover, the oxygen defects are occurring along with sulfur‐doping in MoO₃, enabling efficient electron transport. As expected, the fiber‐shaped S‐MoO_3?x achieves outstanding capacitance with good rate capability and long cycling life. More impressively, the fiber‐shaped ASC based on S‐MoO_3?x anode delivers extremely high volumetric capacitance of 6.19 F cm^?3 at 0.5 mA cm^?1, which makes it promising as one of the most attractive candidates of anode materials for high‐performance fiber‐shaped ASCs.     

Flexible Broadband Graphene Photodetectors Enhanced by Plasmonic Cu3−xP Colloidal Nanocrystals

The integration of graphene with colloidal quantum dots (QDs) that have tunable light absorption affords new opportunities for optoelectronic applications as such a hybrid system solves the problem of both quantity and mobility of photocarriers. In this work, a hybrid system comprising of monolayer graphene and self‐doped colloidal copper phosphide (Cu_3?x P) QDs is developed for efficient broadband photodetection. Unlike conventional PbS QDs that are toxic, Cu_3?x P QDs are environmental friendly and have plasmonic resonant absorption in near‐infrared (NIR) wavelength. The half‐covered graphene with Cu_3?x P nanocrystals (NCs) behaves as a self‐driven p–n junction and shows durable photoresponse in NIR range. A comparison experiment reveals that the surface ligand attached to Cu_3?x P NCs plays a key role in determining the charge transfer efficiency from Cu_3?x P to graphene. The most efficient three‐terminal photodetectors based on graphene‐Cu_3?x P exhibit broadband photoresponse from 400 to 1550 nm with an ultrahigh responsivity (1.59 × 10⁵ A W^?1) and high photoconductive gain (6.66 × 10⁵) at visible wavelength (405 nm), and a good responsivity of 9.34 A W^?1 at 1550 nm. The demonstration of flexible graphene‐Cu_3?x P photodetectors operated at NIR wavelengths may find potential applications in optical sensing, biological imaging, and wearable devices.     

Self‐Templated Fabrication of MoNi4/MoO3‐x Nanorod Arrays with Dual Active Components for Highly Efficient Hydrogen Evolution

A binder‐free efficient MoNi₄/MoO_3‐x nanorod array electrode with 3D open structure is developed by using Ni foam as both scaffold and Ni source to form NiMoO₄ precursor, followed by subsequent annealing in a reduction atmosphere. It is discovered that the self‐templated conversion of NiMoO₄ into MoNi₄ nanocrystals and MoO_3‐x as dual active components dramatically boosts the hydrogen evolution reaction (HER) performance. Benefiting from high intrinsic activity, high electrochemical surface area, 3D open network, and improved electron transport, the resulting MoNi₄/MoO_3‐x electrode exhibits a remarkable HER activity with extremely low overpotentials of 17 mV at 10 mA cm^?2 and 114 mV at 500 mA cm^?2, as well as a superior durability in alkaline medium. The water–alkali electrolyzer using MoNi₄/MoO_3‐x as cathode achieves stable overall water splitting with a small cell voltage of 1.6 V at 30 mA cm ^{? 2}. These findings may inspire the exploration of cost‐effective and efficient electrodes by in situ integrating multiple highly active components on 3D platform with open conductive network for practical hydrogen production.     

Silver‐Quantum‐Dot‐Modified MoO3 and MnO2 Paper‐Like Freestanding Films for Flexible Solid‐State Asymmetric Supercapacitors

Free‐standing paper‐like thin‐film electrodes have great potential to boost next‐generation power sources with highly flexible, ultrathin, and lightweight requirements. In this work, silver‐quantum‐dot‐ (2–5 nm) modified transition metal oxide (including MoO₃ and MnO₂) paper‐like electrodes are developed for energy storage applications. Benefitting from the ohmic contact at the interfaces between silver quantum dots and MoO₃ nanobelts (or MnO₂ nanowires) and the binder‐free nature and 0D/1D/2D nanostructured 3D network of the fabricated electrodes, substantial improvements on the electrical conductivity, efficient ionic diffusion, and areal capacitances of the hybrid nanostructure electrodes are observed. With this proposed strategy, the constructed asymmetric supercapacitors, with Ag quantum dots/MoO₃ “paper” as anode, Ag quantum dots/MnO₂ “paper” as cathode, and neutral Na₂SO₄/polyvinyl alcohol hydrogel as electrolyte, exhibit significantly enhanced energy and power densities in comparison with those of the supercapacitors without modification of Ag quantum dots on electrodes; present excellent cycling stability at different current densities and good flexibility under various bending states; offer possibilities as high‐performance power sources with low cost, high safety, and environmental friendly properties.     

Plasmonic Au x Ag y bimetallic alloy nanoparticles enhanced photoluminescence upconversion of Er3+ ions in antimony glass hybrid nanocomposites

Er³⁺ ions and spherical (3–23?nm) Au _x Ag _y bimetallic alloy (where x?=?18–96 and y?=?4–82, atom %) nanoparticles incorporated novel antimony oxide based reducing dielectric (glass) matrix, K₂O–B₂O₃–Sb₂O₃ (KBS), has been synthesized by a new single step methodology involving selective thermochemical reduction. Their absorption spectra show a single tunable (536–679 nm) surface plasmon resonance band along with the typical absorption peaks of the Er³⁺ ion. X-ray and SAED indicate the formation of (111) and (200) planes of Au _x Ag _y alloy. The luminescence intensity of two prominent emission bands of Er³⁺ ions centered at 536 (green) and 645 (red) nm due to ⁴S_3/2 → ⁴I_15/2 and ⁴F_9/2 → ⁴I_15/2 transitions were observed to be strongly dependent on the Au _x Ag _y nanoparticle composition. Both the bands undergo a maximum of 1.5- and 4.5-fold intensity enhancement respectively in the presence of the Ag₅₆Au₄₄ alloy (atom %) due to plasmon induced local field enhancement.     

Perovskite Quantum Dots and Their Application in Light‐Emitting Diodes

Perovskite quantum dots (PQDs) attract significant interest in recent years because of their unique optical properties, such as tunable wavelength, narrow emission, and high photoluminescence quantum efficiency (PLQY). Recent studies report new types of formamidinium (FA) PbBr₃ PQDs, PQDs with organic–inorganic mixed cations, divalent cation doped colloidal CsPb_1?xM_xBr₃ PQDs (M = Sn²⁺, Cd²⁺, Zn²⁺, Mn²⁺) featuring partial cation exchange, and heterovalent cation doped into PQDs (Bi³⁺). These PQD analogs open new possibilities for optoelectronic devices. For commercial applications in lighting and backlight displays, stability of PQDs requires further improvement to prevent their degradation by temperature, oxygen, moisture, and light. Oxygen and moisture‐facilitated ion migration may easily etch unstable PQDs. Easy ion migration may result in crystal growth, which lowers PLQY of PQDs. Surface coating and treatment are important procedures for overcoming such factors. In this study, new types of PQDs and a strategy of improving their stabilities are introduced. Finally, this paper discusses future applications of PQDs in light‐emitting diodes.     

P Doped MoO3−x Nanosheets as Efficient and Stable Electrocatalysts for Hydrogen Evolution

A P doped MoO_3?x nanocomposite material with rich oxygen vacancies is successfully fabricated by a two‐step intercalation method, which presents superior activity for the hydrogen evolution reaction with low overpotential and fast electron transfer. In 0.5 m H₂SO₄, it displays an overpotential of 166 mV for driving the current density of 10 mA cm^?2. Moreover, it also shows a good catalytic stability in the electrolytes with different pH, 0.5 m H₂SO₄ (strong acid), 0.5 m Na₂SO₄ (neutral solution), and 0.1 m NaOH (strong base). The superior catalytic activity and stability are due to to the synergistic effect between the P element doping and the oxygen vacancies.     

Oxygen Vacancy‐Engineered PEGylated MoO3−x Nanoparticles with Superior Sulfite Oxidase Mimetic Activity for Vitamin B1 Detection

Sulfite oxidase (SuO_x) is a molybdenum‐dependent enzyme that catalyzes the oxidation of sulfite to sulfate to maintain the intracellular levels of sulfite at an appropriate low level. The deficiency of SuO_x would cause severe neurological damage and infant diseases, which makes SuO_x of tremendous biomedical importance. Herein, a SuO_x mimic nanozyme of PEGylated (polyethylene glycol)‐MoO_3?x nanoparticles (P‐MoO_3?x NPs) with abundant oxygen vacancies created by vacancy‐engineering is reported. Their level of SuO_x‐like activity is 12 times higher than that of bulk‐MoO₃. It is also established that the superior increased enzyme mimetic activity is due to the introduction of the oxygen vacancies acting as catalytic hotspots, which allows better sulfite capture ability. It is found that vitamin B1 (VB1) inhibits the SuO_x mimic activity of P‐MoO_3?x NPs through the irreversible cleavage by sulfite and the electrostatic interaction with P‐MoO_3?x NPs. A colorimetric platform is developed for the detection of VB1 with high sensitivity (the low detection limit is 0.46 µg mL^?1) and good selectivity. These findings pave the way for further investigating the nanozyme which possess intrinsic SuO_x mimicing activity and is thus a promising candidate for biomedical detection.     

Interfacial Engineering Coupled Valence Tuning of MoO3 Cathode for High‐Capacity and High‐Rate Fiber‐Shaped Zinc‐Ion Batteries

Aqueous Zn‐ion batteries (ZIBs) have garnered the researchers' spotlight owing to its high safety, cost effectiveness, and high theoretical capacity of Zn anode. However, the availability of cathode materials for Zn ions storage is limited. With unique layered structure along the [010] direction, α‐MoO₃ holds great promise as a cathode material for ZIBs, but its intrinsically poor conductivity severely restricts the capacity and rate capability. To circumvent this issue, an efficient surface engineering strategy is proposed to significantly improve the electric conductivity, Zn ion diffusion rate, and cycling stability of the MoO₃ cathode for ZIBs, thus drastically promoting its electrochemical properties. With the synergetic effect of Al₂O₃ coating and phosphating process, the constructed Zn//P‐MoO_3?x@Al₂O₃ battery delivers impressive capacity of 257.7 mAh g^?1 at 1 A g^?1 and superior rate capability (57% capacity retention at 20 A g^?1), dramatically surpassing the pristine Zn//MoO₃ battery (115.8 mAh g^?1; 19.7%). More importantly, capitalized on polyvinyl alcohol gel electrolyte, an admirable capacity (19.2 mAh cm^?3) as well as favorable energy density (14.4 mWh cm^?3; 240 Wh kg^?1) are both achieved by the fiber‐shaped quasi‐solid‐state ZIB. This work may be a great motivation for further research on molybdenum or other layered structure materials for high‐performance ZIBs.     

Performance enhancement of paper-based SERS chips by shell-isolated nanoparticle-enhanced Raman spectroscopy

Paper-based flexible surface-enhanced Raman scattering (SERS) chips have been demonstrated to have great potential for future practical applications in point-of-care testing (POCT) due to the potentials of massive fabrication, low cost, efficient sample collection and short signal acquisition time. In this work, common filter paper and Ag@SiO₂core-shell nanoparticles (NP) have been utilized to fabricate SERS chips based on shell‐isolated nanoparticle‐enhanced Raman spectroscopy (SHINERS). The SERS performance of the chips for POCT applications was systematically investigated. We used crystal violet as the model molecule to study the influence of the size of the Ag core and the thickness of the SiO₂coating layer on the SERS activity and then the morphology optimized Ag@SiO₂core-shell NPs was employed to detect thiram. By utilizing the smartphone as a miniaturized Raman spectral analyzer, high SERS sensitivity of thiram with a detection limit of 10⁻⁹M was obtained. The study on the stability of the SERS chips shows that a SiO₂shell of 3 nm can effectively protect the as-prepared SERS chips against oxidation in ambient atmosphere without seriously weakening the SERS sensitivity. Our results indicated that the SERS chips by SHINERS had great potential of practical application, such as pesticide residues detection in POCT.     

MoOx thin films deposited by magnetron sputtering as an anode for aqueous micro-supercapacitors

Abstract

In order to examine the potential application of non-stoichiometric molybdenum oxide as anode materials for aqueous micro-supercapacitors, conductive MoO_x films (2  x  2.3) deposited via RF magnetron sputtering at different temperatures were systematically studied for composition, structure and electrochemical properties in an aqueous solution of Li₂SO₄. The MoO_x (x ≈ 2.3) film deposited at 150 °C exhibited a higher areal capacitance (31 mF cm^?2 measured at 5 mV s^?1), best rate capability and excellent stability at potentials below ?0.1 V versus saturated calomel electrode, compared to the films deposited at room temperature and at higher temperatures. These superior properties were attributed to the multi-valence composition and mixed-phase microstructure, i.e., the coexistence of MoO₂ nanocrystals and amorphous MoO_x (2.3 < x  3). A mechanism combining Mo(IV) oxidation/reduction on the hydrated MoO₂ grain surfaces and cation intercalation/extrusion is proposed to illustrate the pseudo-capacitive process.     

Topotactic redox reactions and ion exchange of layered MoO3 bronzes

Chemical or electrochemical reduction of MoO₃ in neutral aqueous electrolyte solutions results in the reversible topotactic formation of a new type of molybdenum oxide bronzes A⁺_x(H₂O)_y[MoO₃]^x?. The latter are built up by negatively charged [MoO₃]^x? layers with exchangeable hydrated cations in the interlayer space. Non-solvated cations are taken up between the MoO₃ sheets on cathodic reduction of the oxide in organic electrolyte solutions. Galvanostatic studies on the reduction of MoO₃ in aqueous acids reveal the strong influence of kinetics on hydrogen ion uptake. Earlier results of Glemser (2) on “genotypic” hydrogen bronzes of MoO₃ are confirmed. H_0.5MoO₃ was found to exhibit Brönsted acid character and to form a novel type of layer intercalation compounds L_xH_0.5MoO₃ with Lewis bases.     

Surface-ligand protected reduction on plasmonic tuning of one-dimensional MoO3−x nanobelts for solar steam generation

Sub-stoichiometric MoO_3−x nanostructures with plasmonic absorption via creating oxygen vacancies have attracted extensive attentions for many intriguing applications. However, the synthesis of one-dimensional (1D) plasmonic MoO_3−x nanostructures with widely tunable plasmonic absorption has remained a significant challenge because of their serious morphological destruction and phase change with increasing the concentration of oxygen vacancies. Here we demonstrate a surface-ligand protected reduction strategy for the synthesis of 1D MoO_3−x nanobelts with tunable plasmonic absorption in a wide wavelength range from 200 to 2,500 nm. Polyethylene glycol (PEG-400) is used as both the reductant to produce oxygen vacancies and the surface protected ligands to maintain 1D morphology during the formation process of MoO_3−x nanobelts, enabling the widely tunable plasmonic absorption. Owing to their broad plasmonic absorption and unique 1D nanostructure, we further demonstrate the application of 1D MoO_3−x nanobelts as photothermal film for interfacial solar evaporator. The surface-ligand protected reduction strategy provides a new avenue for the developing plasmonic semiconductor oxides with maintained particle morphology and thus enriching their wide applications.

     

Functional Femtoliter Droplets for Ultrafast Nanoextraction and Supersensitive Online Microanalysis

A universal femtoliter surface droplet‐based platform for direct quantification of trace of hydrophobic compounds in aqueous solutions is presented. Formation and functionalization of femtoliter droplets, concentrating the analyte in the solution, are integrated into a simple fluidic chamber, taking advantage of the long‐term stability, large surface‐to‐volume ratio, and tunable chemical composition of these droplets. In situ quantification of the extracted analytes is achieved by surface‐enhanced Raman scattering (SERS) spectroscopy by nanoparticles on the functionalized droplets. Optimized extraction efficiency and SERS enhancement by tuning droplet composition enable quantitative determination of hydrophobic model compounds of rhodamine 6G, methylene blue, and malachite green with the detection limit of 10^?9 to 10^?11 m and a large linear range of SERS signal from 10^?9 to 10^?6 m of the analytes. The approach addresses the current challenges of reproducibility and the lifetime of the substrate in SERS measurements. This novel surface droplet platform combines liquid–liquid extraction and highly sensitive and reproducible SERS detection, providing a promising technique in current chemical analysis related to environment monitoring, biomedical diagnosis, and national security monitoring.     

Ultrafine NiFe-Based (Oxy)Hydroxide Nanosheet Arrays with Rich Edge Planes and Superhydrophilic-Superaerophobic Characteristics for Oxygen Evolution Reaction

NiFe-based (oxy)hydroxides are the benchmark catalysts for the oxygen evolution reaction (OER) in alkaline medium, however, it is still challenging to control their structures and compositions. Herein, molybdates (NiFe(MoO₄)_x) are applied as unique precursors to synthesize ultrafine Mo modified NiFeO_xH_y (oxy)hydroxide nanosheet arrays. The electrochemical activation process enables the molybdate ions (MoO₄²⁻) in the precursors gradually dissolve, and at the same time, hydroxide ions (OH⁻) in the electrolyte diffuse into the precursor and react with Ni²⁺ and Fe³⁺ ions in confined space to produce ultrafine NiFeO_xH_y (oxy)hydroxides nanosheets (<10 nm), which are densely arranged into microporous arrays and maintain the rod-like morphology of the precursor. Such dense ultrafine nanosheet arrays produce rich edge planes on the surface of NiFeO_xH_y (oxy)hydroxides to expose more active sites. More importantly, the capillary phenomenon of microporous structures and hydrophilic hydroxyl groups induce the superhydrophilicity and the rough surface produces the superaerophobic characteristic for bubbles. With these advantages, the optimized catalyst exhibits excellent performance for OER, with a small overpotential of 182 mV at 10 mA cm⁻² and long-term stability (200 h) at 200 mA cm⁻². Theoretical calculations show that the modification of Mo enhances the electron delocalization and optimizes the adsorption of intermediates.     

Wafer‐Scale Double‐Layer Stacked Au/Al2O3@Au Nanosphere Structure with Tunable Nanospacing for Surface‐Enhanced Raman Scattering

Fabricating perfect plasmonic nanostructures has been a major challenge in surface enhanced Raman scattering (SERS) research. Here, a double‐layer stacked Au/Al₂O₃@Au nanosphere structures is designed on the silicon wafer to bring high density, high intensity “hot spots” effect. A simply reproducible high‐throughput approach is shown to fabricate feasibly this plasmonic nanostructures by rapid thermal annealing (RTA) and atomic layer deposition process (ALD). The double‐layer stacked Au nanospheres construct a three‐dimensional plasmonic nanostructure with tunable nanospacing and high‐density nanojunctions between adjacent Au nanospheres by ultrathin Al₂O₃ isolation layer, producing highly strong plasmonic coupling so that the electromagnetic near‐field is greatly enhanced to obtain a highly uniform increase of SERS with an enhancement factor (EF) of over 10⁷. Both heterogeneous nanosphere group (Au/Al₂O₃@Ag) and pyramid‐shaped arrays structure substrate can help to increase the SERS signals further, with a EF of nearly 10⁹. These wafer‐scale, high density homo/hetero‐metal‐nanosphere arrays with tunable nanojunction between adjacent shell‐isolated nanospheres have significant implications for ultrasensitive Raman detection, molecular electronics, and nanophotonics.     

MXenes for Plasmonic Photodetection

MXenes have recently shown impressive optical and plasmonic properties associated with their ultrathin‐atomic‐layer structure. However, their potential use in photonic and plasmonic devices has been only marginally explored. Photodetectors made of five different MXenes are fabricated, among which molybdenum carbide MXene (Mo₂CT_x) exhibits the best performance. Mo₂CT_x MXene thin films deposited on paper substrates exhibit broad photoresponse in the range of 400–800 nm with high responsivity (up to 9 A W^?1), detectivity (≈5 × 10¹¹ Jones), and reliable photoswitching characteristics at a wavelength of 660 nm. Spatially resolved electron energy‐loss spectroscopy and ultrafast femtosecond transient absorption spectroscopy of the MXene nanosheets reveal that the photoresponse of Mo₂CT_x is strongly dependent on its surface plasmon‐assisted hot carriers. Additionally, Mo₂CT_x thin‐film devices are shown to be relatively stable under ambient conditions, continuous illumination and mechanical stresses, illustrating their durable photodetection operation in the visible spectral range. Micro‐Raman spectroscopy conducted on bare Mo₂CT_x film and on gold electrodes allowing for surface‐enhanced Raman scattering demonstrates surface chemistry and a specific low‐frequency band that is related to the vibrational modes of the single nanosheets. The specific ability to detect and excite individual surface plasmon modes provides a viable platform for various MXene‐based optoelectronic applications.     

Carbon‐Intercalated 0D/2D Hybrid of Hematite Quantum Dots/Graphitic Carbon Nitride Nanosheets as Superior Catalyst for Advanced Oxidation

Efficient charge separation and sufficiently exposed active sites are important for light‐driving Fenton catalysts. 0D/2D hybrids, especially quantum dots (QDs)/nanosheets (NSs), offer a better opportunity for improving photo‐Fenton activity due to their high charge mobility and more catalytic sites, which is highly desirable but remains a great challenge. Herein, a 0D hematite quantum dots/2D ultrathin g‐C₃N₄ nanosheets hybrid (Fe₂O₃ QDs/g‐C₃N₄ NS) is developed via a facile chemical reaction and subsequent low‐temperature calcination. As expected, the specially designed 0D/2D structure shows remarkable catalytic performance toward the removal of p‐nitrophenol. By virtue of large surface area, adequate active sites, and strong interfacial coupling, the 0D Fe₂O₃ QDs/2D g‐C₃N₄ nanosheets establish efficient charge transport paths by local in‐plane carbon species, expediting the separation and transfer of electron/hole pairs. Simultaneously, highly efficient charge mobility can lead to continuous and fast Fe(III)/Fe(II) conversion, promoting a cooperative effect between the photocatalysis and chemical activation of H₂O₂. The developed carbon‐intercalated 0D/2D hybrid provides a new insight in developing heterogeneous catalysis for a large variety of photoelectronic applications, not limited in photo‐Fenton catalysis.