High Charge Transfer Efficiency Research Articles

A Novel Synthesis of Nickel Carbide Modified Glassy Carbon Electrode for Electrochemical Investigation of Archetypal Diabetes Biomarker in Human Serum and Urine Samples

We began with an exploration of a novel method for non-enzymatic glucose sensing through the direct electrochemical oxidation process using an annealed Nickel carbide (Ni3C) modified glassy carbon electrode (GCE). We cover the synthesis and detailed characterization of Ni3C, the modification process of the electrode, and its application in the electrocatalytic detection of glucose in human blood and urine samples. Ni3C, known for its high charge transfer efficiency, exceptional stability in harsh environments, and outstanding electrochemical activity, was prepared through an annealing method. The produced Ni3C, characterized by a nanoplate structure ranging from 20 to 50 nanometers, was applied to a GCE to benefit from its extensive surface area and structural robustness. Electrochemical impedance spectroscopy and cyclic voltammetry confirmed the superior electrocatalytic properties and charge transfer capabilities of Ni3C/GCE over the unmodified GCE. The glucose detection was achieved by the direct electrochemical oxidation of glucose on the modified electrode, showcasing a linear detection range from 0.05 to 2236 μM and an impressively low detection limit of 0.0186 μM. This research underscores the effectiveness of Ni3C/GCE as durable, efficient, and reliable tools for the non-enzymatic electrochemical sensing of glucose, providing new prospects for diabetes monitoring.

Probing charge transfer of NiCo2O4/g-C3N4 photocatalyst for hydrogen production

Quantum dots/two-dimensional (0D/2D) semiconductor photocatalysts demonstrate wide solar light absorption region and high charge transfer efficiency. However, the relation between the interfacial electric field and the charge transfer during the photocatalytic hydrogen production process is still unclear. Here, we construct NiCo2O4 quantum dots (QDs) and NiCo2O4 nanoparticles (NPs) anchored with 2D g-C3N4 (CN) to form NiCo2O4-QDs/CN and NiCo2O4-NPs/CN heterojunctions. The hydrogen production rate of CN loaded with NiCo2O4 QDs is about 3 times higher than that of CN loaded with NiCo2O4 NPs. The electric field intensity at the NiCo2O4-QDs/CN interface is calculated to be about 15,600 V cm−2, about 9 times higher than that of NiCo2O4-NPs/CN, which could effectively drive the electrons of CN to flow toward NiCo2O4 QDs, promoting photocarriers separation and hence greatly improving the photocatalytic performance. This work provides a method to understand the relationship between interfacial electric field strength and photogenerated charges of heterostructure photocatalysts.

Highly efficient nitrogen fixation over S-scheme heterojunction photocatalysts with enhanced active hydrogen supply.

Photocatalytic N2 fixation is a promising strategy for ammonia (NH3) synthesis; however, it suffers from relatively low ammonia yield due to the difficulty in the design of photocatalysts with both high charge transfer efficiency and desirable N2 adsorption/activation capability. Herein, an S-scheme CoSx/ZnS heterojunction with dual active sites is designed as an efficient N2 fixation photocatalyst. The CoSx/ZnS heterojunction exhibits a unique pocket-like nanostructure with small ZnS nanocrystals adhered on a single-hole CoSx hollow dodecahedron. Within the heterojunction, the electronic interaction between ZnS and CoSx creates electron-deficient Zn sites with enhanced N2 chemisorption and electron-sufficient Co sites with active hydrogen supply for N2 hydrogenation, cooperatively reducing the energy barrier for N2 activation. In combination with the promoted photogenerated electron-hole separation of the S-scheme heterojunction and facilitated mass transfer by the pocket-like nanostructure, an excellent N2 fixation performance with a high NH3 yield of 1175.37 μmol g-1 h-1 is achieved. This study provides new insights into the design of heterojunction photocatalysts for N2 fixation.

Construction of site-specific magnetic Z-scheme CdS/Fe3O4@N-doped graphene aerogel microtube/N-doped TiO2 with porous structure: enhanced catalytic performance in photo-Fenton reaction.

The development of composite photocatalysts with high charge transfer efficiency, great visible light absorption, and quick recovery has aroused the interest of many researchers. Herein, based on the hydrothermal assisted vacuum freeze drying method, CdS, Fe3O4, and N-TiO2 were, respectively, fixed in the inner, middle, and outer layers of nitrogen-doped graphene aerogel for preparation of the site-specific magnetic porous Z-scheme CdS/Fe3O4@N-doped graphene aerogel microtube/N-doped TiO2 (CdS/Fe3O4@NGAM/N-TiO2) photocatalyst. For the composite, Fe3O4@NGAM carrier with porous and tubular structure not only helps the recycle and reactants/productions mass transport in the photocatalytic process but also ensures the well-steered transfer of electrons and holes from CdS and N-TiO2 in the Z-type heterojunction system, greatly improving the separation of photogenerated carriers. Besides, Fe3O4 can also work as a Fenton catalyst to activate hydrogen peroxide which is generated in situ by CdS. Thus, the CdS/Fe3O4@NGAM/N-TiO2 composite presents excellent degradation efficiencies towards methyl orange ((MO) 98% removal rate within 50min), bisphenol A ((BPA) 96% removal rate within 50min), tetracycline hydrochloride ((TCH) 96% removal rate within 120min) and strong stabilities after 6 cycles. The free radical removal experiments show that ·O2- and ·OH are the main active substances of catalysis, which further confirms the synergistic effect of photocatalysis and Fenton catalysis.

Two birds with one stone: Facile fabrication of a ternary ZnIn2S4/BiVO4/MWCNTs nanocomposite for photocatalytic detoxification of priority organic pollutants and hydrogen production with a proposed mechanism

A series of ternary nanocomposites with different weight percentages of zinc indium sulfide, bismuth vanadate, and multiwalled carbon nanotubes (ZnIn2S4/BiVO4/MWCNTs) were synthesized using a simple thermal impregnation method to obtain high charge separation and transfer efficiency, thus improving their photocatalytic performance. The 20 wt% ZnIn2S4/BiVO4/MWCNTs (20 wt% ZBM) nanocomposite exhibited enhanced photocatalytic activity compared to pure BiVO4 and ZnIn2S4 for the degradation of methylene blue, acetaminophen, and allopurinol in an aqueous solution when exposed to a visible light source and atmospheric oxygen. This nanocomposite demonstrated a particularly high degradation rate constant (k = 6.39 × 10−2 min−1) for the photocatalytic degradation of methylene blue. The introduction of MWCNTs boosted the photocatalytic performance of the 20 wt% ZBM nanocomposite, attaining a maximum H2 production of 1704 μmol g−1. Repeated photocatalytic H2 generation reached 1621 μmol g−1 after 5 h of irradiation with four consecutive cycles. Therefore, we propose a “two birds with one stone” strategy for greatly improved photocatalytic wastewater detoxification and H2 production by prolonging the lifetime of the photogenerated electron–hole pair separation.

2D Metal–Organic Framework Nanosheets based on Pd‐TCPP as Photocatalysts for Highly Improved Hydrogen Evolution

AbstractIn this report, a 2D MOF nanosheet derived Pd single‐atom catalyst, denoted as Pd‐MOF, was fabricated and examined for visible light photocatalytic hydrogen evolution reaction (HER). This Pd‐MOF can provide a remarkable photocatalytic activity (a H2 production rate of 21.3 mmol/gh in the visible range), which outperforms recently reported Pt‐MOFs (with a H2 production rate of 6.6 mmol/gh) with a similar noble metal loading. Notably, this high efficiency of Pd‐MOF is not due to different chemical environment of the metal center, nor by changes in the spectral light absorption. The higher performance of the Pd‐MOF in comparison to the analogue Pt‐MOF is attributed to the longer lifetime of the photogenerated electron‐hole pairs and higher charge transfer efficiency.

In-situ self-assembled flower-like ZnIn2S4/CdIn2S4 composites with enhanced interfacial charge transfer and photocatalytic degradation of atrazine

In heterostructure photocatalysts, interface charge transfer is a crucial step in the photocatalytic process, so it is crucial to construct photocatalysts with high interface charge transfer efficiency. Here we report an in-situ self-assembled flower-like ZnIn2S4/CdIn2S4 (ZCIS) composites with excellent catalytic performance for atrazine (ATZ) degradation. The ZCIS-4 composite could degrade 99.82% of ATZ within 40 min, which showed 1.42 and 1.91 times better than blank ZnIn2S4 and CdIn2S4, respectively. The excellent catalytic performance is attributed to the built-in electric field in the in-situ self-assembled composite photocatalyst, which accelerates the rapid transfer of interfacial charges and the rapid separation of photogenerated electron hole pairs. The toxicity assessment shown that some intermediates exhibited decreased toxicities; however, the toxicities were still significant. Active radical capture experiments and electron spin resonance characterization demonstrated that h+, O2− were the main active free radicals. Differential charge density simulation calculations verified that interface photogenerated electrons were transported from CIS to the ZIS surface.

Modulating the Photoresponsivity of Perovskite Photodetectors through Interfacial Engineering of Self‐Assembled Monolayers

AbstractPhotodetectors are one of the most essential optoelectronics nowadays. Perovskites have emerged as one of the potential materials for photodetectors due to their high absorption efficiency over a wide range of wavelengths, high charge mobility, strong mechanical deformability, and solution processability. In this study, interfacial engineering using self‐assembled monolayers (SAMs) is explored to improve the performance of perovskite photodetectors. SAMs with different terminal groups exhibit distinct surface energy, and they all result in a reduced exciton lifetime of the perovskite due to charge transfer between polycrystalline perovskite and the SAMs. In particular, the photodetector modified with (4‐hydroxyphenyl)phosphonic acid (OH) exhibits the highest electron mobility of 0.8 cm2 V−1 s−1 under 450‐nm light illumination. In addition, it shows excellent detector performance with an ultrafast photoresponse of < 14 ms, a high photoresponsivity of 5600 AW−1, and a high specific detectivity of 5.9 × 1010 Jones at a low light intensity of 18 µW cm−2. The excellent photoresponse and device switchability are attributed to the high surface energy of OH, the resulting homogeneous perovskite film morphology, the high charge transfer efficiency, and the favorable energy level alignment. The studies provide new prospects for the development of emerging perovskite photodetectors.

Cheap transition metal reinforced donor–acceptor covalent organic frameworks for CO2 photoreduction

Artificial photoreduction of CO2 is considered an attractive solution for simultaneously achieving carbon neutrality goals and solving the energy shortage crisis. In this study, a donor–acceptor (D–A) covalent organic framework (COF), COF-BT, comprising (1,1′-biphenyl)-3,3′,5,5′-tetracarbaldehyde and 4,4′-(2,1,3-benzothiadiazole-4,7-diyl)bis[benzenamine] was prepared, and cheap CoO was introduced into COF-BT via a two-step impregnation-calcination process to obtain Co-COF-BT with immobilized transition metals. Photoelectrochemical experimental and theoretical results indicate that the D–A structure of Co-COF-BT reduces the band gap, enhances visible light absorption, inhibits electron–hole recombination, and prolongs the life of photogenerated carriers. The introduction of CoO provides additional active sites, and the Co-S bond in Co-COF-BT provides an additional channel for ultrafast electron migration from the COF-BT unit to the CoO active center, which increases charge mobility and reduces the energy barrier formed by *COOH intermediates. Thus, the excellent photocatalytic CO2 reduction activity of Co-COF-BT is achieved with a CO yield of 2423 μmol g−1h−1 and selectivity > 99% under visible light. The superior photocatalytic performance is attributed to the synergistic effect of D–A moieties and CoO in Co-COF-BT. This study not only presents a novel COF-based photocatalyst with high charge transfer efficiency and high catalytic activity in CO2 reduction but also provides a potential strategy to fine-tune photoelectronic properties by adjusting the functional building blocks and additional metal active sites.

Ultra-high output hybrid nanogenerator for self-powered smart mariculture monitoring and warning system

Remote monitoring of distributed mariculture based on Internet of Things (IoT) has become an important part of smart marine agriculture, however, attaining stable and long-lasting power supply from conventional commercial batteries remains challenging, which significantly restricts the development of blue economic toward intelligent and diversified. Herein, a self-powered monitoring and warning system (SMWS) for smart mariculture based on a nodding duck structured multi-layer hybrid triboelectric-electromagnetic generator (MHTEG) is developed that endows improved electrical output performances and energy conversion efficiency. The structure of multi-electrode pairs is investigated with various ratios of nylon rod diameter to electrode width for optimizing the charge transfer efficiency of MHTEG. A peak output power density of 20.9 W/m3, ultra-high output energy of 39.6 mJ and excellent energy conversion efficiency of 22.61% can be achieved by the MHTEG with a high charge transfer efficiency of over 88%. Moreover, combining the MHTEG with an anti-theft and seawater sensor module, the remote SMWS is designed for monitoring and providing early-warning in marine farming. Such a design renders a practicable strategy and generic energy solution for efficient ocean wave energy scavenging and enabling distributed mariculture with intelligence.

Facile and environmentally friendly synthesis of highly efficient two-dimensional hematene nanosheets for photocatalytic applications

Exfoliation of bulk hematite (α-Fe2O3), as an environmentally friendly, nontoxicity, and low-cost semiconductor oxide, exhibited greater photocatalytic activity under visible light irradiation. Herein, we described two preparation methods of novel two-dimensional non-van der Waals hematene (2D-Hm) nanosheets including ultrasound-assisted liquid-phase exfoliation (US-Hm) and chemical-assisted liquid-phase exfoliation (CH-Hm). The photocatalytic activity of 2D-Hm nanosheets was evaluated for the decomposition of Tetracycline (TC). Various advanced analyses were used to investigate the physical and chemical properties of the exfoliated samples. SEM and TEM analyses confirmed the layered structures of 2D-Hm. The crystalline structure of 2D-Hm samples was confirmed successfully by XRD analyses. After exfoliation of bulk hematite, the surface area increased remarkably from 5.73 m2/g to 24.16, and 15.26 m2/g using US-Hm, and CH-Hm exfoliation methods, respectively. The photoelectrochemical photocurrent and electrochemical impedance spectroscopy (EIS) analysis indicate that 2D-Hm samples have higher charge-transfer efficiency than bulk hematite. Additionally, the formation of hydroxyl (•OH) radicals was approved using the o-phenylenediamine (OPD) and photoluminescence (PL) analysis. The leaching iron concentration in the aqueous phase was measured within five consecutive examinations. To recognize the intermediates formed during the degradation process, gas chromatography-mass spectrometry (GC–MS) was employed.

Constructing 2D/2D La2Ce2O7/g-C3N4 S-scheme heterojunction for markedly enhanced interfacial charge separation and photocatalytic activity under visible light irradiation

It is an effective strategy to improve photocatalytic degradation performance by constructing step scheme (S-scheme) heterojunction photocatalysts with superior photo-redox capacity and high charge transfer efficiency. In this study, a series of two-dimensional/two-dimensional (2D/2D) La2Ce2O7/g-C3N4 (LCO/CN) S-scheme heterojunction photocatalysts were synthesized via in-situ solid-phase sintering by regulating the mass ratio of raw materials. The large junction area between La2Ce2O7 nanosheets and ultra-thin graphitic carbon nitride (g-C3N4) endows the composite with significantly enhanced separation and transfer efficiency of photogenerated carriers within a satisfactory light response region. The LCO/CN-2 composite not only shows the highest photocatalytic activity with a reaction rate constant of 0.02701 min−1 to degrade Rhodamine B (RhB) under visible light irradiation for 90 min but also demonstrates stable reusability after four runs. Moreover, based on the Mott-Schottky calculations, radical trapping experiments, and ESR analysis,·O2- and·OH are identified as the main active species, and an S-scheme charge transfer mechanism is suggested to explain the enhanced photocatalytic activity. This work inspires the application of fluorite-type photocatalysts to wastewater purification and environmental restoration.

Hydrophilic ZnO/C nanocomposites with superior adsorption, photocatalytic, and photo-enhanced antibacterial properties for synergistic water purification

Owing to the numerous potential applications of ZnO nanomaterials, the development of ZnO-based nanocomposites has become of great scientific interest in various fields. In this paper, we are reporting the fabrication of a series of ZnO/C nanocomposites through a simple “one-pot” calcination method under three different temperatures, 500 ℃, 600 ℃, and 700 ℃, with samples labeled as ZnO/C-500, -600, and -700, respectively. All samples exhibited adsorption capabilities and photon-activated catalytic and antibacterial properties, with the ZnO/C-700 sample showing superior performance among the three. The carbonaceous material in ZnO/C is key to expanding the optical absorption range and improving the charge separation efficiency of ZnO. The remarkable adsorption property of the ZnO/C-700 sample was demonstrated using Congo red dye, and is credited to its good hydrophilicity. It was also found to exhibit the most notable photocatalysis effect due to its high charge transfer efficiency. The hydrophilic ZnO/C-700 sample was also examined for antibacterial effects both in vitro (against Escherichia coli and Staphylococcus aureus) and in vivo (against MSRA-infected rat wound model), and it was observed to exhibit synergistic killing performance under visible-light irradiation. A possible cleaning mechanism is proposed on the basis of our experimental results. Overall, this work presents a facile way of synthesizing ZnO/C nanocomposites with outstanding adsorption, photocatalysis, and antibacterial properties for the efficient treatment of organic and bacterial contaminants in wastewater.

Nitrogen vacancy/oxygen dopants designed nanoscale hollow tubular g-C3N4 with excellent photocatalytic hydrogen evolution and photodegradation

In this study, N vacancies and O heteroatoms were decorated onto hollow nanotubes carbon nitride (UMCN-3) via hydrolyzation-precipitation-calcination method to prepare high-performance photocatalyst for hydrogen evolution and photodegradation. Plenty of hollow nanotubes with diameter of 30–50 nm endowed UMCN-3 with abundant active sites and high charge transfer efficiency. Nitrogen vacancies/oxygen dopants not only created defect states but also acted as trapping centers, thus triggering the charge rearrangement to obtain high electronic transport efficiency, as evidenced by experimental results and theoretical calculations (DFT). The hydrogen evolution rate of optimal UMCN-3 sample was 23-times higher than that of pristine g-C3N4, and still at a high level in seawater. The photocatalytic degradation activity for RhB and TC of UMCN-3 also improved greatly. The superb photocatalytic performance can be put down to the three-in-one synergistic effect on N vacancies, O doped and hollow nanotubes.

Enhanced piezocatalytic hydrogen evolution performance of bismuth vanadate by the synergistic effect of facet engineering and cocatalyst engineering

Developing piezocatalysts with excellent piezocatalytic hydrogen evolution reaction (HER) performance is highly desired but also challenging. Here, facet engineering and cocatalyst engineering are employed to synergistically improve the piezocatalytic HER efficiency of BiVO4 (BVO). Monoclinic BVO catalysts with distinct exposed facets are synthesized by adjusting pH of hydrothermal reaction. The BVO with highly exposed {110} facet exhibits a superior piezocatalytic HER performance (617.9 μmol g-1h−1) compared with that with {010} facet, owing to the strong piezoelectric property, high charge transfer efficiency, and excellent hydrogen adsorption/desorption capacity. The HER efficiency is enhanced by 44.7% by selectively depositing cocatalyst of Ag nanoparticles specifically on the reductive {010} facet of BVO, where the Ag-BVO interface provides the directional electron transport for high-efficiency charge separation. Under the collaboration between cocatalyst of CoOx on {110} facet and the hole sacrificial agent of methanol, the piezocatalytic HER efficiency is evidently enhanced by 2 times because CoOx and methanol can impede the water oxidation and improve the charge separation. This easy and simple strategy provides an alternative perspective on designing high-performance piezocatalysts.

High-Performance Visible-Light Photocatalysts for H2 Production: Rod-Shaped Co3O4/CoO/Co2P Heterojunction Derived from Co-MOF-74

Photocatalyst systems generally consist of catalysts and cocatalysts to realize light capture, charge carrier migration, and surface redox reactions. Developing a single photocatalyst that performs all functions while minimizing efficiency loss is extremely challenging. Herein, rod-shaped photocatalysts Co3O4/CoO/Co2P are designed and prepared using Co-MOF-74 as a template, which displays an outstanding H2 generation rate of 6.00 mmol·g−1·h−1 when exposed to visible light irradiation. It is 12.8 times higher than pure Co3O4. Under light excitation, the photoinduced electrons migrate from the catalysts of Co3O4 and CoO to the cocatalyst Co2P. The trapped electrons can subsequently undergo a reduction reaction to produce H2 on the surface. Density functional theory calculations and spectroscopic measurements reveal that enhanced performance results from the extended lifetime of photogenerated carriers and higher charge transfer efficiency. The ingenious structure and interface design presented in this study may guide the general synthesis of metal oxide/metal phosphide homometallic composites for photocatalysis.

Dithienobenzothiadiazole (DTBT)-Based Polymers Enable Organic Solar Cells with Ultrahigh VOC of ≈1.3V.

Dithieno[3',2':3,4;2",3":5,6]benzo[1,2-c][1,2,5]thiadiazole (DTBT) is a newly emerging building block to construct effective photovoltaic polymers. Organic solar cells (OSCs) based on DTBT-based polymers have realized power conversion efficiency (PCEs) over 18%, despite their relatively low open-circuit voltage (VOC ) of 0.8-0.95V. To extend the application of DTBT-based polymers in high-voltage OSCs, herein, D18-Cl and PE55 are used to combine with a wide-bandgap non-fullerene acceptor (NFA), BTA3, and achieve ultrahigh VOC of 1.30 and 1.28V, respectively. Compared with D18-Cl based on tricyclic benzodithiophene (BDT) segment, PE55 containing the pentacyclic dithienobenzodithiophene (DTBDT) unit possesses better hole mobility, higher charge-transfer efficiency, and more desirable phase separation. Hence, PE55:BTA3 blend exhibits a higher efficiency of 9.36% than that of D18-Cl: BTA3 combination (6.30%), which is one of the highest values for OSCs at ≈1.3V VOC . This work attests that DTBT-based p-type polymers are ideal for the application in high-voltage OSCs.

The Green Box: Selenoviologen-Based Tetracationic Cyclophane for Electrochromism, Host–Guest Interactions, and Visible-Light Photocatalysis

The novel selenoviologen-based tetracationic cyclophanes (green boxes 3 and 5) with rigid electron-deficient cavities are synthesized via SN2 reactions in two steps. The green boxes exhibit good redox properties, narrow energy gaps, and strong absorption in the visible range (370-470 nm), especially for the green box 5 containing two selenoviologen (SeV2+) units. Meanwhile, the femtosecond transient absorption (fs-TA) reveals that the green boxes have a stabilized dicationic biradical, high efficiency of intramolecular charge transfer (ICT), and long-lived charge separation state due to the formation of cyclophane structure. Based on the excellent photophysical and redox properties, the green boxes are applied to electrochromic devices (ECDs) and visible-light-driven hydrogen production with a high H2 generation rate (34 μmol/h), turnover number (203), and apparent quantum yield (5.33 × 10-2). In addition, the host-guest recognitions are demonstrated between the green boxes and electron-rich guests (e.g., G1:1-naphthol and G2:platinum(II)-tethered naphthalene) in MeCN through C-H···π and π···π interactions. As a one-component system, the host-guest complexes of green box⊃G2 are successfully applied to visible-light photocatalytic hydrogen production due to the intramolecular electron transfer (IET) between platinum(II) of G2 and SeV2+ of the green box, which provides a simplified system for solar energy conversion.

A cellular automata framework for porous electrode reconstruction and reaction-diffusion simulation

Due to the high charge transfer efficiency compared to that of non-porous materials, porous electrodes with larger surface area and thinner solid pore walls have been widely applied in the lithium-ion battery field. Since the capacity and charge-discharge efficiency of batteries are closely related to the microstructure of porous materials, a conceptually simple and computationally efficient cellular automata (CA) framework is proposed to reconstruct the porous electrode structure and simulate the reaction-diffusion process under the irregular solid-liquid boundary in this work. This framework is consisted of an electrode generating model and a reaction-diffusion model. Electrode structures with specific geometric properties, i.e., porosity, surface area, size distribution, and eccentricity distribution can be constructed by the electrode generating model. The reaction-diffusion model is exemplified by solving the Fick’s diffusion problem and simulating the cyclic voltammetry (CV) process. The discharging process in the lithium-ion battery are simulated through combining the above two CA models, and the simulation results are consistent with the well-known pseudo-two-dimensional (P2D) model. In addition, a set of electrodes with different microstructures are constructed and their reaction efficiencies are evaluated. The results indicate that there is an optimum combination of porosity and particle size for discharge efficiency. This framework is a promising one for studying the effect of electrode microstructure on battery performance due to its fully synchronous computation way, easy handled boundary conditions, and free of convergence concerns.

Enhanced visible light catalytic activity of holey Ti3C2 based catalyst for azo dyes

The efficient degradation of organic dye pollutions is of great importance for environmental remediation. In this work, we prepared holey Ti3C2 (H-Ti3C2) and further synthesized H-Ti3C2/Ag/AgX (Cl, Br, I) Schottky catalysts by a simple electrostatic self-assembly method, and found that H-Ti3C2 could significantly improve the catalytic activity and stability of AgX. The H-Ti3C2/Ag/AgX composites showed great visible light absorption, obvious photocurrent intensity, and high charge transfer efficiency, ultimately improving photocatalytic efficacy for the degradation of methyl orange (MO) dye. The composite (5 wt%) H-Ti3C2/Ag/AgBr has the greatest photocatalytic activity, degrading 99.2% of the MO solution after 40 min of visible light irradiation, which is 1.08 and 2.02 times more than (5 wt%) Ti3C2 /Ag/AgBr and Ag/AgBr, respectively. The photocatalytic performance of H-Ti3C2/Ag/AgBr for MO dyes remains at 51% after five cycles. This result indicates that combining H-Ti3C2 with other photosensitive semiconductors to improve the catalytic activity and stability offers great possibilities. The present work not only provides a simplified method for the preparation of H-Ti3C2/Ag/AgX composites, but also offers a great possibility for H-Ti3C2 MXene as a co-catalyst to increase the photocatalytic degradation efficiency of organic pollutants.