High Electron-hole Separation Efficiency Research Articles

Improving charge separation capability of CdS/Bi/Ti3C2Tx nanocomposites for efficient photocatalytic oxidative organic transformations

The development of new strategies to improve the separation of photogenerated carriers is crucial for enhancing photocatalytic efficiency of heterogeneous photocatalysts. Here, we have successfully constructed CdS/Bi/Ti3C2Tx nanocomposites with high electron-hole separation efficiency through coupling Bi and Ti3C2Tx on CdS nanorods. The average emission lifetime of the CdS/Bi/Ti3C2Tx nanocomposites can be up to ca. 6.74 ns, which realizes efficient heterogeneous photocatalysis for oxidative hydroxylation of arylboronic acids and coupling of amines with high yields. The photocatalytic rates are ∼15250 μmol·g−1·h−1 for 4-cyanophenol production and ∼12125 μmol·g−1·h−1 for (E)-N-benzyl-1-phenylmethanimine production, which are twice and three-fold higher than those (∼7500 and ∼4000 μmol·g−1·h−1) of the CdS nanorods, respectively. The high photocatalytic efficiency can be ascribed to the strong electron-hole separation capacity by migrating electrons into Bi and Ti3C2Tx from CdS nanorods. In addition, the CdS/Bi/Ti3C2Tx nanocomposites also have satisfactory sustainable recycling and reuse properties. This work provids a new strategy for constructing heterogeneous metal/semiconductor nanophotocatalysts with strong electron-hole separation capacity for high-efficient light-driven organic transformations.

Nanoengineering construction of g-C3N4/Bi2WO6 S-scheme heterojunctions for cooperative enhanced photocatalytic CO2 reduction and pollutant degradation

S-scheme heterojunction photocatalysts featuring efficient charge transport paths provide a promising strategy for cooperative achieving photocatalytic CO2 reduction reaction (CO2RR) and Rhodamine B (RhB) degradation. In this work, S-scheme heterojunctions composed of g-C3N4 nanosheets coated on Bi2WO6 nanosheets were prepared by a one-step hydrothermal method, resulting in broad-spectrum light absorption, high electron–hole separation efficiency, and excellent photocatalytic CO2 reduction and RhB oxidization performance. Mechanistic analysis revealed the formation of a directional charge transport path at the interface of the heterojunction, which maintained a high oxidation and reduction potential and improved the efficiency of photoexcited carrier separation. In particular, the synergistic reaction system showed excellent photoredox activity compared with the two separate half-reactions. The optimal catalyst 15CN/BWO displayed the highest CO2 conversion efficiency, with CO and CH4 generation rates of 4.3 and 2.7 μmol g−1h−1, respectively, and the degradation efficiency of the composite heterojunction was significantly higher than that of its constituent materials. This work provides a new possibility for designing a novel dual-function photocatalytic reaction system.

Facile preparation of ZIF-67 on TiO2 and enhancement photocathodic protection for 316L stainless steel

Photocathodic protection (PCP) anticorrosion using sunlight is a green and sustainable technology. However, the ease of carriers compounding and the low light utilization are still the main restraints to its development. To develop an effective photoanode, a metal-organic framework (MOF, i.e., ZIF-67) material is electrodeposited and grown in-situ on TiO2 nanorods. The morphological structure, light absorption properties, photoelectrochemical properties and cathodic protection principle of ZIF-67/TiO2 photoanode are analysed by SEM, PL, I-V and EIS. The material characterization and light absorption characteristics show that the photoanode has good light absorption performance and higher electron hole separation efficiency. Photoelectrochemical test shows that ZIF-67/TiO2 photoanode has excellent photocathodic protection for 316L stainless steel (316L SS). ZTRs-60 has the optimal protection effect. Under simulated sunlight, the OCP of 316L SS coupled ZTRs-60 is -0.41 V vs. Ag/AgCl, and the current density of the I-t curve can reach 20 μA/cm2. EIS and Tafel tests show that the photogenerated electrons transfer to the stainless steel surface, which promotes the cathode polarization process and alleviates the metal corrosion.

One-Step Photochemical Preparation of CdS/Poly(MMA-co-MAA) Composite with Enhanced Photocatalytic Activity.

This paper presents a one-step photochemical method for the preparation of CdS/Poly(MMA-co-MAA) composite photocatalyst, based on the concept of simultaneous photocatalytic polymerization of organic monomers during UV-light induced formation of CdS. The preparation is carried out in an aqueous solution of Na2S2O3, CdSO4, methyl methacrylate (MMA) and methacrylic acid (MAA), under a UV lamp. The continuously formed CdS particles with photocatalytic activity act the role of initiator to directly initiate the copolymerization of MMA and MAA, resulting in the in situ formation of the composite and full contact of the CdS particles with the oxygen-containing groups in the polymer. Taking the photocatalytic degradation of methylene blue as a case study, the composite exhibited significantly higher activity under simulated solar light compared to the pure CdS. By analysis on various data, the enhanced photocatalytic activity is attributed to the enhanced visible light absorption, and especially the high electron-hole separation efficiency caused by the electrostatic interaction between photogenerated holes and carbonyl oxygen atoms with negatively charged features. Furthermore, the composite displays excellent sunlight activity and recyclability, suggesting its potential for practical applications. Such a one-step construction strategy relying only on photo-energy is green, low-cost and promising in obtaining high-performance semiconductor/polymer composite photocatalysts.

Bioactive VS4-based sonosensitizer for robust chemodynamic, sonodynamic and osteogenic therapy of infected bone defects

BackgroundMost bone defects caused by bone disease or trauma are accompanied by infection, and there is a high risk of infection spread and defect expansion. Traditional clinical treatment plans often fail due to issues like antibiotic resistance and non-union of bones. Therefore, the treatment of infected bone defects requires a strategy that simultaneously achieves high antibacterial efficiency and promotes bone regeneration.ResultsIn this study, an ultrasound responsive vanadium tetrasulfide-loaded MXene (VSM) Schottky junction is constructed for rapid methicillin-resistant staphylococcus aureus (MRSA) clearance and bone regeneration. Due to the peroxidase (POD)-like activity of VS4 and the abundant Schottky junctions, VSM has high electron–hole separation efficiency and a decreased band gap, exhibiting a strong chemodynamic and sonodynamic antibacterial efficiency of 94.03%. Under the stimulation of medical dose ultrasound, the steady release of vanadium element promotes the osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs). The in vivo application of VSM in infected tibial plateau bone defects of rats also has a great therapeutic effect, eliminating MRSA infection, then inhibiting inflammation and improving bone regeneration.ConclusionThe present work successfully develops an ultrasound responsive VS4-based versatile sonosensitizer for robust effective antibacterial and osteogenic therapy of infected bone defects.

Porphyrin-Based Two-Dimensional Metal-Organic framework nanosheets for efficient photocatalytic CO2 transformation

2D metal − organic framework (MOF) nanosheets have been demonstrated to exhibit excellent properties and prospects in various aspects, especially in photocatalysis. However, the design and direct preparation of 2D MOF photocatalyst is highly desirable but still challenging. Herein, a novel 2D porphyrin-based MOF Fe-DBP(Co), which is assembled by dicarboxylic porphyrin ligands and the unprecedented undecametallic ferric-oxo clusters, is designed and developed. The unique nanosheet morphology and assembled layered structure endows the photocatalyst with higher electron-hole separation efficiency and longer photogenerated carrier lifetime compared to the analogous MOFs. Consequently, Fe-DBP(Co) exhibits strikingly excellent and stable photocatalytic performance in CO2 cycloaddition, and the reaction rate of 103.2 mmol∙g−1∙h−1 is among the state-of-the-art cases for MOF-photocatalyzed CO2 cycloaddition. The underlying mechanism investigation suggested that photogenerated electrons transferred from CoDBP ligands to the Fe clusters, and the abundant electrons and holes promoted the generation of Fe(II) and Co(III) respectively, leading to excellent catalytic performance. This work proposes a new strategy to design and develop efficient MOF photocatalysts for photocatalytic transformation of CO2.

Enhanced photoelectrocatalytic performance of ZnO/Co3O4 nanoflowers modified TiO2 nanotube array under visible light

The efficient degradation of organic pollutants from the water has been attracted greater public attention and remains to be the main challenge of environmental problems. In this work, ZnO/Co3O4 nanoflowers are deposited on the surface of TiO2 nanotube arrays (ZnCo-TiO2) via the one-pot hydrothermal method by adjusting the Zn/Co ratios. The images of scanning electron microscope show that the ZnCo11-TiO2 (the addition of the Zn/Co ratios is 1:1) presents nano spherical nano-flowers morphologies. In addition, the energy bandgap of ZnCo11-TiO2 is calculated to be 2.8 eV by UV–visible diffuse reflectance spectroscope, which was smaller than that of other semples. Moreover, the lowest peak intensity of photoluminescence spectroscopy for ZnCo11-TiO2 indicates that it has high electron-hole separation efficiency. From the results of UV–visible diffuse reflectance spectroscope and EIS, we can see that ZnCo11-TiO2 has a wider spectral absorption range (200–380 nm and 450–800 nm) and a smaller electron transfer impedance (137.4 Ω). The photoelectrocatalytic removal efficiencies of ZnCo11-TiO2 is 97.5% toward the removal of methylene blue (MB), which is higher than that of other semples. The excellent photoelectrocatalytic performances of ZnCo11-TiO2 are ascribed to the high visible light absorption and rapid transportation of photogenerated electrons on ZnO/Co3O4 nanoflowers. In addition, this paper tentatively stated the detailed photoelectrocatalytic mechanism of ZnCo11-TiO2 electrode for the removal of MB.

InN@In2S3 Core-Shell nanorod for oxygen-free and penetration depth-unrestricted photodynamic therapy against glioblastoma

Photodynamic therapy (PDT) is among the most promising antineoplastic protocols for glioblastoma (GBM). Nonetheless, GBM is a deep-seated intracranial tumor with a serious hypoxic microenvironment; thus, ensuring a sufficient light penetration depth and oxygen (O2) supply are crucial to achieving a positive therapeutic outcome against GBM using PDT. Herein, InN@In2S3 core–shell nanorods are designed to serve as novel and indispensable PDT agents for GBM treatment. Unlike other PDT agents, InN@In2S3 features wide and strong near-infrared absorption that may improve the penetration depth. Moreover, InN@In2S3 exhibits high electron–hole separation efficiency owing to its Ⅱ heterojunction. The separated holes catalyze the generation of O2 from H2O, thereby ensuring sufficient O2 supply for generating reactive oxygen species through a redox reaction between the generated O2 and separated electrons. Our study demonstrates an O2-free and penetration depth-unrestricted PDT strategy that will promote the clinical treatment of GBM with PDT.

Photocatalytic Oxidative Coupling of Ethane to n-Butane Using CO2 as a Soft Oxidant over NiTi-Layered Double Hydroxide.

Selective conversion of ethane (C2 H6 ) to high-value-added chemicals is a very important chemical process, yet it remains challenging owing to the difficulty of ethane activation. Here, a NiTi-layered double hydroxide (NiTi-LDH) photocatalyst is reported for oxidative coupling of ethane to n-butane (n-C4 H10 ) by using CO2 as an oxidant. Remarkably, the as-prepared NiTi-LDH exhibits a high selectivity for n-C4 H10 (92.35%) with a production rate of 62.06 µmol g-1 h-1 when the feed gas (CO2 /C2 H6 ) ratio is 2:8. The X-ray absorption fine structure (XAFS) and photoelectron characterizations demonstrate that NiTi-LDH possesses rich vacancies and high electron-hole separation efficiency, which can promote the coupling of C2 H6 to n-C4 H10 . More importantly, density functional theory (DFT) calculations reveal that ethane is first activated on the oxygen vacancies of the catalyst surface, and the C─C coupling pathway is more favorable than the C─H cleavage to C2 H4 or CH4 , resulting in the high production rate and selectivity for n-C4 H10 .

Comparative study on the effects of {2 0 1} TiO2 and {2 0 1}TiO2−ZrO2 on arsenite photocatalysis

Escalated levels of arsenic (As) in drinking water is an urgent environmental problem that has attracted increasing public concern. The need for effective removal of As has motivated great research efforts. Herein, {2 0 1} TiO2 and its Zr doped composite were compared in reducing As toxicity via photocatalysis. Macroscopic photocatalytic kinetics show that the oxidization process of As(III) catalyzed by {2 0 1} TiO2, {2 0 1} TiO2 − ZrO2, and ZrO2 followed first-order kinetics with a rate constant of {2 0 1} TiO2 >{2 0 1}TiO2 − ZrO2 > ZrO2. UV–vis DRS and photoluminescence results suggested that the photooxidizing activity of {2 0 1} TiO2 outdone {2 0 1}TiO2 − ZrO2 due to its narrower band gap and higher electron-hole separation efficiency. After 190 min of UV irradiation, the quantum yields of •OH during {2 0 1} TiO2 and {2 0 1}TiO2 − ZrO2 photocatalysis were 146.1 and 112.6 μM, respectively. As evidenced by the radical-scavenging test, photocatalytically generated h+ and O2•- were the predominant participants in As(III) photooxidation for {2 0 1} TiO2 and {2 0 1}TiO2 − ZrO2, respectively. The photocatalytic mechanism gained from the investigation would be helpful for developing high-index TiO2-based environmental techniques.

Efficient photoelectrochemical aptasensing of di-2-ethylhexyl phthalate in environmental samples based on N, S co-doped graphene quantum dots/TiO2 nanorods

An efficient photoelectrochemical (PEC) sensing platform was developed for detection of di-2-ethylhexyl phthalate (DEHP) based on nitrogen and sulfur co-doped graphene quantum dots/TiO2 nanorods (N, S-GQDs/TiO2 NRs) coupling with exonuclease I (Exo I)-assisted target recycling for remarkable signal amplification. N, S-GQDs uniformly grown on TiO2 NRs by simple hydrothermal method showed high electron-hole separation efficiency and superior photoelectric performance, which was explored as the photoactive substrate for anchoring anti-DEHP aptamer and its complementary DNA (cDNA). With the addition of DEHP, aptamer molecules fell from the electrode surface owing to the specific recognition of aptamer to DEHP, resulting in the increment of photocurrent signal. At this moment, Exo I could stimulate aptamer hydrolysis in the aptamer-DEHP complexes, so that DEHP was released from the complexes to take part in the next reaction cycling, which remarkably increasing the photocurrent response and achieving signal amplification. The designed PEC sensing platform exhibited excellent analytical performance for DEHP with a low detection limit of 0.1 pg L−1. Also, its applications in real samples were further investigated in detail. Thus, the established method would provide a simple and efficient tool for DEHP or other pollutants monitoring in the environment.

Piezo-potential induced redox of polyaniline and CdS/PANI heterostructures for efficient photoelectrochemical water splitting

Photoelectrode materials with high electron-hole separation efficiency and long-lasting stability are extremely important for photoelectrochemical (PEC) water separation. In this paper, the CdS/PANI composite structure was prepared by a simple hydrothermal method to improve the stability of CdS while maximizing its excellent PEC properties. This system (CdS/PANI) utilizes the redox effect of PANI internal functional groups to accomplish electron-hole migration, which suppresses the photocorrosion of CdS without using any surface sacrificial agent. Meanwhile, the carrier separation is further promoted by the heterojunction structure formed by CdS/PANI under the stimulation of ultrasonic waves. The coordination of the above two effects achieves improved photocatalytic activity and enhanced stability. The electrochemical test results under ultrasonic conditions showed that the PANI composite on CdS increased the photocurrent density (1.23 V vs. RHE) from 1.68 mA/cm−2 to 2.62 mA/cm−2 compared to pure CdS. In addition, the stability of PEC is further enhanced and the photocorrosion rate decreases from 43% to 12%. This strategy provides a promising example for the development of more efficient organic-inorganic piezoelectric photoanode materials.

Biomimetic Guided Bi2WO6/Bi2O3 Vertical Heterojunction with Controllable Microstructure for Efficient Photocatalysis

To bridge the technical gap of heterojunction induction control in conventional semiconductor photocatalysts, a method of regulating the growth of heterojunctions utilizing biomimetic structures was designed to prepare a series of Bi2WO6/Bi2O3 vertical heterojunction nanocomposites for the disposal of environmentally hazardous tetracycline wastewater difficult to degrade by conventional microbial techniques. Porous Bi2O3 precursors with high-energy crystalline (110) dominant growth were produced using the sunflower straw bio-template technique (SSBT). Bi2WO6 with a (131) plane grew preferentially into 2.8 to 4 nm pieces on the (110) plane of Bi2O3, causing a significant density reduction between Bi2WO6 pieces and a dimensional decrease in the agglomerated Bi2WO6 spheres from 3 μm to 700 nm since Bi2WO6 grew on the structure of the biomimetic Bi2O3. The optimal 1:8 Bi2WO6/Bi2O3 coupling catalyst was obtained via adapting the ratio of the two semiconductors, and the coupling ratio of 1:8 minimized the adverse effects of the overgrowth of Bi2WO6 on degradation performance by securing the quantity of vertical heterojunctions. The material degradation reaction energy barrier and bandgap were significantly reduced by the presence of a large number of vertical heterojunction structures, resulting in a material with lower impedance and higher electron-hole separation efficiency; thus, the degradation efficiency of 1:8 Bi2WO6/Bi2O3 for tetracycline hydrochloride reached 99% within 60 min. In conclusion, this study not only successfully synthesized a novel photocatalyst with potential applications in water pollution remediation but also introduced a pioneering approach for semiconductor-driven synthesis.

Multiple roles of 2D conductive metal-organic framework enable noble metal-free photocatalytic hydrogen evolution

Developing advanced catalysts with high electron-hole separation efficiency and sufficient active centers for redox reaction is vital for photocatalytic hydrogen evolution. Herein, a synergetic system constructed by 2D conductive Ni3(HITP)2 MOF and TiO2 was elaborated to address this challenge for the first time. Photoelectrochemical experiments verify that Ni3(HITP)2 can greatly facilitate the charge separation and charge transfer efficiency of the catalytic heterostructure of Ni3(HITP)2/TiO2. Meanwhile, photocatalytic hydrogen evolution reaction, UPS tests and EPR measurement indicate that Ni3(HITP)2 can serve as co-catalyst which can provide reactive sites for hydrogen reduction. Benefiting from the multiple roles of Ni3(HITP)2, the photosensitive inorganic semiconductor and conductive MOF synergistically realize noble-metal free photocatalysis, rendering>7 times improved hydrogen evolution performance than pristine TiO2. This work gives insight into the mechanism of electroconductive MOF as cocatalyst for hydrogen evolution, which will further inspire the design of advanced electroconductive MOF applied for photocatalysis.

Zinc vacancy mediated electron-hole separation in ZnO nanorod arrays for high-sensitivity organic photoelectrochemical transistor aptasensor.

A novel strong solvent coordination leaching method was developed to prepare surface zinc vacancies in ZnO nanorod arrays. Remarkably, the surface-zinc-vacancy-rich ZnO nanorod arrays exhibit high electron-hole separation efficiency and excellent photoelectrochemical performance for use as a promising candidate for the next generation of organic photoelectrochemical transistor aptasensors.

Recyclable SERS monitoring of food quality based on the shrubby morphology of titania oxide-triggered electromagnetic “hotspots”

Constructing of plasmonic substrate with the capability of detecting nutritional food quality will soon be emerged as the frontier research directions with broad prospects in surface-enhanced Raman scattering (SERS) technology ascribed to an improvement of living standards. Herein, a novel TiO2 framework with a shrubby morphology was successfully constructed on carbon cloth (CC) matrix to trigger significantly enhanced electromagnetic “hotspots” after dense Ag network with numerous sharp corners and edges was formed by a photo-induced reduction. Particularly, the structure-dependent optical performance was investigated for these as-prepared CC/TiO2/Ag hybrid substrates, screening out an optimal one with an enhancement factor of 6.38 × 107. Regarding a prominent photocatalytic efficiency ascribed to the high electron-hole separation efficiency assisted by the CC matrix and Ag decoration, a recyclable SERS-based monitoring of quercetin (QR) was achieved in teas, demonstrating recovery values distributed from 88.9 % to 106.4 %. The strategy proposed here opened a new way to create high-density “hotspots” for multifunctional SERS substrates, which might play a crucial role in food quality monitoring applications.

Macrophage-Targeted Sonodynamic/Photothermal Synergistic Therapy for Preventing Atherosclerotic Plaque Progression Using CuS/TiO2 Heterostructured Nanosheets.

Sonodynamic therapy (SDT) and photothermal therapy (PTT) are two effective strategies for the treatment of atherosclerotic plaques. However, the low yield of reactive oxygen species (ROS) of conventional organic sonosensitizers and the low biosafety of hyperthermia limit the therapeutic efficacy of SDT and PTT. Herein, we report copper sulfide/titanium oxide heterostructure nanosheets modified with hyaluronic acid (HA) and PEG (HA-HNSs) for low-intensity sonodynamic and mild-photothermal synergistic therapy for early atherosclerotic plaques. CuS/TiO2 heterostructure nanosheets (HNSs) show high electron-hole separation efficiency and superior sonodynamic performance, because it has high surface energy crystal facets as well as a narrow band. Moreover, HNSs exhibit intense absorbance in the NIR-II region, which endows the nanosheets with excellent photothermal performance. With a further modification of HA, HA-HNSs can selectively target intraplaque proinflammatory macrophages through CD44-HA interaction. Because SDT reduces the expression of heat shock protein 90 and PTT facilitates the sonocatalytic process, the combination of SDT and PTT based on HA-HNSs could synergistically induce proinflammatory macrophage apoptosis. More importantly, the synergistic therapy prevents the progression of early atherosclerotic plaque by removing lesional macrophages and mitigating inflammation. Taken together, this work provides a macrophage-targeting sonodynamic/photothermal synergistic therapy, which is an effective translational clinical intervention for early atherosclerotic plaques.

Fabrication of TiO2/CeO2/CeFeO3 tandem n-n heterojunction nanocomposites for visible-light-triggered photocatalytic degradation of tetracycline and colored effluents

In this work, the TiO2 integrated CeO2/CeFeO3 nanocomposites with tandem n-n heterojunctions were synthesized and utilized as visible-light-triggered photocatalysts for photodegradation of aquatic contaminants. The ternary TiO2/CeO2/CeFeO3 nanocomposite with optimum composition exhibited a significant photocatalytic performance for the degradation of tetracycline, methylene blue, fuchsine, and rhodamine B with rate constants of 358 × 10−4, 416 × 10−4, 302.3 × 10−4, and 220 × 10−4 min−1, which were 39.0, 22.3, 21.3, and 22.8 times higher than those of pristine TiO2, respectively. Thanks to the created tandem n-n heterojunctions, the high electron-hole separation efficiency and facile migration of charge carriers were found as the major causes of the powerful degradation outcomes. This study establishes an inexpensive and effortless approach for synthesizing innovative series of heterogeneous photocatalysts to address the water pollution crisis.

Photocatalytic Performance of Perovskite and Metal-Organic Framework Hybrid Material for the Reduction of N2 to Ammonia.

The orthorhombic phase of KNbO3 perovskite has been applied for nitrogen (N2) photoreduction to ammonia (NH3). However, this material suffers from a low surface area and low ammonia production efficiency under UV light irradiation. To eliminate these barriers, we used a metal-organic framework (MOF), named as TMU-5 ([Zn(OBA)(BPDH)0.5]n·1.5DMF, where H2OBA = 4,4'-oxybis(benzoic acid) and BPDH = 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene), for the synthesis of the KNbO3@TMU-5 hybrid material. KNbO3@TMU-5 achieved a NH3 production rate of 39.9 μmol·L-1·h-1·g-1 upon UV light irradiation, as compared to 20.5 μmol·L-1·h-1·g-1 recorded for KNbO3 under similar experimental conditions. Using different characterization techniques especially gas adsorption, cyclic voltammetry, X-ray photoelectron spectroscopy, photocurrent measurements, and Fourier transform infrared spectroscopy, it has been found that the higher photoactivity of KNbO3@TMU-5 in ammonia production is due to its higher surface area, higher electron-hole separation efficiency, and higher density of negative charges on Nb sites. This work shows that hybridization of conventional semiconductors (SCs) with photoactive MOFs can improve the photoactivity of the SC@MOF hybrid material in different reactions, especially kinetically complex reactions like photoconversion of nitrogen to ammonia.

Biomass porous carbon as the active site to enhance photodegradation of oxytetracycline on mesoporous g-C3N4.

Graphitic carbon nitride (g-C3N4) is widely used in photocatalytic adsorption and degradation of pollutants, but there are still some problems such as low adsorption performance and high electron–hole recombination efficiency. Herein, we propose a new molten salt assisted thermal polycondensation strategy to synthesize biomass porous carbon (BPC) loaded on g-C3N4 composites (designated as BPC/g-C3N4) with a hollow tubular structure, which had a high surface area and low electron–hole recombination rate. The study shows that the morphology of g-C3N4 changes dramatically from massive to hollow tubular by molten salt assisted thermal polycondensation, which provides a base for the loading of BPC, to construct a highly effective composite photocatalyst. BPC loaded on g-C3N4 could be used as the active site to enhance Oxytetracycline (OTC) removal efficiency by adsorption and with higher electron–hole separation efficiency. As a result, the BPC(5%)/g-C3N4 sample presented the highest photocatalytic degradation efficiency (84%) for OTC degradation under visible light irradiation. The adsorption capacity and photocatalytic reaction rate were 3.67 and 5.63 times higher than that of the g-C3N4, respectively. This work provided a new insight for the design of novel composite photocatalysts with high adsorption and photocatalytic performance for the removal of antibiotic pollutants from wastewater.