Recombination Of Photogenerated Carriers Research Articles

Bi-piezoelectric effect assisted ZnO nanorods/PVDF-HFP spongy photocatalyst for enhanced performance on degrading organic pollutant

Piezoelectric field engineering has been recently proved to restrain the photogenerated carrier recombination both in the bulk and on the surface of photocatalyst. Herein, we proposed a bi-piezoelectric ZnO nanorods (NR)/PVDF-HFP spongy film that can utilize water flow vibration to boost the photocatalytic degradation of organic dye. The composite photocatalyst can be deformed by water flow to generate an integrated piezoelectric field from PVDF-HFP and ZnO NR, which can considerably drive the separation and transfer of photogenerated charge carriers in ZnO NR. As a result, the ZnO NR/PVDF-HFP spongy film shows a ∼ 3 fold increase in reaction rate constant of degrading methyl orange (MO) with irradiation as flow speed increases from 200 rpm to 1000 rpm. A model about the bi-piezoelectric effect of ZnO NR/PVDF-HFP was configurated according to a series of characterization by piezoelectric force microscopy (PFM) and photoluminescence (PL). This work demonstrates the contribution of the bi-piezoelectric effect to photocatalytic water decontamination and provides a promising strategy to use dual-sustainable energy— solar and water energy.

Molybdenum nitride as a metallic photoelectrocatalyst for hydrogen evolution reaction via introduction of electron traps to improve the separation efficiency of photogenerated carriers

Metallic photoelectrocatalysts possess a wide light absorption range and the fast hydrogen evolution reaction (HER) kinetics, which can be used as the next generation of catalysts towards photoelectrocataytic HER. In this work, molybdenum nitride has been fabricated via an in-suit growth method on metal molybdenum substance (Mo 3 N 2 /Mo foil). The metallic and optical property of Mo 3 N 2 was confirmed by the DFT calculations and experimental results from UV–visible absorption spectrum and valence X-ray photoelectron spectroscopy spectrum. Photocatalytic HER rate of Mo 3 N 2 reached to 158.78 μmol h −1 g −1 . Furthermore, Mo 3 N 2 –MoS 2 /Mo foil was prepared to improve photoelectrocatalytic performance. Herein, a suitable energy band alignment for Mo 3 N 2 –MoS 2 /Mo foil was proposed based on experiments and DFT calculations, and the formation of a heterojunction (Mo 3 N 2 –MoS 2 ) effectively suppressed the recombination of photo-generated carriers. The results of photoelectrocatalytic experiments suggested that the photocurrent density of Mo 3 N 2 –MoS 2 /foil was effectively enhanced about 1.5 times than that of simplex Mo 3 N 2 /Mo foil. The electrochemical experiments (LSV and EIS) indicated that the metallic nature of Mo 3 N 2 was also beneficial to electrocatalytic HER, and the overpotential of Mo 3 N 2 –MoS 2 /Mo foil at 10 mA cm −2 was −173 mV. This work provides a potential candidate for photoelectrocatalytic electrodes. • Metallic Mo 3 N 2 plays a dominant role in photoelectrocatalytic HER activity. • The metallic and optical nature were verified by experiments and DFT calculation. • Mo 3 N 2 –MoS 2 heterojunction was used to improve the photoelectrocatalytic property. • Schottky barrier effectively suppress the recombination of photoinduced carriers. • Mo 3 N 2 –MoS 2 /Mo foil electrode exhibits superior stability for HER.

Titanium oxide nanotube film decorated with β-Ga2O3 nanoparticles for enhanced water splitting properties

TiO2 is a wide bandgap material with inherent photogenerated charge carrier recombination problems, which reduces its photoelectrochemical (PEC) water splitting efficiency. Considerable efforts have been dedicated to reducing this charge recombination problems by decorating the film’s surface using transition metal nanoparticles (NP) to enhanced device performance. And considerable numbers of literature reports are available to this respect. However, reports are rare for the surface modification of TiO2 nanotubes (TNT) arrays with metal oxide, specially by β-Ga2O3 nanostructures and its potential applications. Herein, the PEC water splitting properties of β-Ga2O3 NP (GNP)-modified TNT arrays is described. The TNT were synthesized by anodization, whereas the GNP were fabricated by chemical vapour deposition method. X-ray diffraction (XRD) results revealed the presence of weak β-Ga2O3 peaks and reduction in crystallite size upon GNP addition. The integration of GNP on the TNT arrays resulted in a slight increase in optical bandgap from 3.4 to 3.6 eV observed by UV–vis measurements. Linear sweep voltammetry measurement for the modified TNT photocatalyst showed a 32.5% enhancement in photocurrent density compared to the bare TNT photoelectrode, measured in 1 M HCl solution. Elemental analysis confirmed the presence of β-Ga2O3, thereby supporting the XRD and UV–vis results. This study demonstrates that GNP-activated TNT arrays could be used as photoanode for enhanced photocatalytic activity in the PEC cell.

Study on AuNPs size regulation and AuNPs/BP photocatalytic performance

As a new two-dimensional material, black phosphorus (BP) has many advantages, like layer-dependent direct band gap, wide spectral response, high carrier mobility and abundant active sites. It is widely used in photocatalysis, solar energy conversion and other fields. However, the rapid recombination of photo-generated carriers and poor chemical stability limit the development of BP in the field of photocatalysis. In this study, a composite photocatalyst was configurated by loading Au nanoparticles (AuNPs) on the surface of the BP, namely AuNPs/BP. By adjusting the conditions such as reducing agent, protective agent, temperature, gold source in the reaction system, the mechanism and influencing factors of AuNPs particle size were explored. The composite catalyst was characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), ultraviolet–visible spectrometry (UV–vis), X-ray photoelectron energy spectrometry (XPS), and photochemical test platforms. Next, the catalytic performance of AuNPs/BP was evaluated by photocatalytic degradation of methyl orange (MO). The results showed that the degradation performance of AuNPs/BP on MO is significantly better than that of pure BP, and the degradation rate increased from 49.7% to 67.7%. The apparent rate constant increased from 5.726 × 10−3min−1 to 9.418 × 10−3min−1. Due to the surface proton resonance effect of AuNPs, BP with AuNPs evenly loaded on the surface showed strong absorption of visible light, high carrier separation efficiency, and widened the band gap of BP.

A feasible and effective solution-processed PCBM electron extraction layer enabling the high VOC and efficient Cu2ZnSn(S, Se)4 devices

Photo-generated carrier recombination loss at the CZTSSe/CdS front interface is a key issue to the open-circuit voltage (VOC) deficit of Cu2ZnSnSxSe4−x(CZTSSe) solar cells. Here, by the aid of an easy-handling spin-coating method, a thin PCBM ([6,6]-phenyl-C61-butyric acid methyl ester) layer as an electron extraction layer has been introduced on the top of CdS buffer layer to modify CZTSSe/CdS/ZnO-ITO (In2O3:Sn) interfacial properties. Based on Sn4+/DMSO (dimethyl sulfoxide) solution system, a total-area efficiency of 12.87% with a VOC of 529 mV has been achieved. A comprehensive investigation on the influence of PCBM layer on carrier extraction, transportation and recombination processes has been carried out. It is found that the PCBM layer can smooth over the CdS film roughness, thus beneficial for a dense and flat window layer. Furthermore, this CZTSSe/CdS/PCBM heterostructure can accelerate carrier separation and extraction and block holes from the front interface as well, which is mainly ascribed to the downward band bending of the absorber and a widened space charge region. Our work provides a feasible way to improve the front interfacial property and the cell performance of CZTSSe solar cells by the aid of organic interfacial materials.

Construction of WO3/CsPbBr3 S-scheme heterojunction via electrostatic Self-assembly for efficient and Long-Period photocatalytic CO2 reduction

Owing to the severe photogenerated carriers recombination and low oxidation ability, the photocatalytic performance of pristine CsPbBr3 is still unsatisfactory. Herein, melamine foam supported S-scheme WO3/CsPbBr3 heterojunction is successfully synthesized by electrostatic self-assembly. Because of the appropriate energy level positions, an S-scheme charge migration route between CsPbBr3 and WO3 is constructed. Under solar light irradiation, melamine foam assisted WO3/CsPbBr3 exhibits significantly enhanced photocatalytic CO2 reduction performance under liquid H2O medium, and the electron consumption rate (Relectron) reaches to 1225.50 μmol.g−1.h−1, which is 1.49- and 13.7-fold of CsPbBr3 and WO3, respectively, ascribing to the boosted charges transfer and the strengthened redox ability. Furthermore, S-scheme WO3/CsPbBr3 heterojunction also exhibits strong durability, with no noticeable reduction of product yields after four 8-h cycles.

Efficient and long-term photocatalytic H2 evolution stability enabled by Cs2AgBiBr6/MoS2 in aqueous HBr solution

Lead-free Cs 2 AgBiBr 6 (CABB) double perovskite as a new-type photocatalytic material alternative to lead halide perovskites holds promise to implement the solar-H 2 conversion, but the interior recombination of photo-generated carriers and thus low photocatalytic hydrogen evolution reaction (HER) rate of CABB restrict its further industrial applications. Herein, we report the composite fabrication of MoS 2 /CABB heterostructure for high-efficiency and durable photocatalytic HER by anchoring non-noble MoS 2 onto CABB via a facile dissolution-recrystallization method. The optimized MoS 2 /CABB performs a visible-light HER rate of 87.5 μmol h −1 g −1 in aqueous HBr solution, ca. 20-fold compared to that of pure CABB (4.3 μmol h −1 g −1 ), and presents a discontinuous 500-h photocatalytic HER stability with no evident loss. The superb performance of MoS 2 /CABB can be ascribed to the kinetics-facilitated heterostructure consisting of stable CABB and MoS 2 . This work proposes a facile and versatile tactic to construct a low-cost Cs 2 AgBiBr 6 -based heterostructure for efficient and long-term photocatalytic HER. • Lead-free CABB/MoS 2 are prepared by a facile dissolution-recrystallization method. • CABB/MoS 2 achieves boosted charge transfer by the constructed heterostructure. • CABB/MoS 2 owns both high visible-light HER rates and long-term stability. • CABB/MoS 2 exhibits superb photocatalytic HER stability during 500-h cyclic test.

Distinctive Deep-Level Defects in Non-Stoichiometric Sb2 Se3 Photovoltaic Materials.

Characterizing defect levels and identifying the compositional elements in semiconducting materials are important research subject for understanding the mechanism of photogenerated carrier recombination and reducing energy loss during solar energy conversion. Here it shows that deep‐level defect in antimony triselenide (Sb2Se3) is sensitively dependent on the stoichiometry. For the first time it experimentally observes the formation of amphoteric SbSe defect in Sb‐rich Sb2Se3. This amphoteric defect possesses equivalent capability of trapping electron and hole, which plays critical role in charge recombination and device performance. In comparative investigation, it also uncovers the reason why Se‐rich Sb2Se3 is able to deliver high device performance from the defect formation perspective. This study demonstrates the crucial defect types in Sb2Se3 and provides a guidance toward the fabrication of efficient Sb2Se3 photovoltaic device and relevant optoelectronic devices.

Microstructure Characterization and Battery Performance Comparison of MOF-235 and TiO2-P25 Materials

The growing interest in energy storage has led to the urgent need for the development of high-performance cathode electrodes. The commercialized materials MOF-235 and TiO2-P25 exhibit characteristics that may be suitable as electrodes but there are inherent challenges that have yet to be addressed in the literature. In this study, a high-pressure hydrothermal synthesized MOF-235 and sol-gel-made TiO2-P25 were tested for battery performance. The results indicate that MOF-235 does not possess the desired performance due to uncontrollable agglomeration. On the other hand, TiO2-P25 showed good cycling life, and the performance can be further optimized by doping and minimizing the particle size. Additionally, SEM and TEM were applied for surface characterization, providing evidence that mesoporous TiO2-25 inhibits photo-generated carrier recombination. The mesoporous energy storage mechanism of those two materials is also discussed. This research will provide technical support for the industrialization of those two mesoporous materials.

In-situ formation of nanosized 1T-phase MoS2 in B-doped carbon nitride for high efficient visible-light-driven H2 production

The high photogenerated carrier recombination rate and the low visible light utilization limit the development of graphitic carbon nitride (CN) in industrial photocatalytic H2 generation. Herein, 1T-phase MoS2 nanoparticles with high conductivity and more active sites are in-situ grown on B-doped carbon nitride (CNB) nanosheets through a one-step hydrothermal method. The doping of boron element effectively improves the harvesting visible light ability by tuning the energy gap, while the introduction of 1T-phase MoS2 successfully increases the carrier transfer rate by suppressing charge trapping. An optimized H2 production activity of 5334 μmol h−1 g−1 with the apparent quantum efficiency of 10.2% is achieved by 1T-MoS2/CNB sample, which is 167 times higher than that of pure CN. The mechanism is systematically illustrated by the combination of DFT calculations and transient absorption measurements. This work provides a new way for the construction of transition metal-derived co-catalysts in photocatalytic hydrogen energy storage.

Photoelectrochemical and photo-Fenton mechanism of enhanced visible light-driven nanocatalyst synthesis of ZnFe2O4/BiOI.

Based on the fact that the photo-Fenton process can directly use solar energy to degrade various pollutants, it has received widespread attention. However, it has attracted widespread attention due to the rapid recombination of photo-generated carriers and the low light response range. Therefore, the construction of a Z-scheme heterojunction in this paper can effectively enhance the electron-hole separation, increase the reduction and oxidation potential, and enhance the redox capability of the photocatalysis. This paper reports the successful preparation of visible-light-induced ZnFe2O4/BiOI composite photocatalysis. There is a Z-scheme heterojunction structure of ZnFe2O4 and BiOI. At the same time, the PL and UV absorption spectra showed that the light absorption performance of the composite nanomaterials was enhanced, the photo-generated carrier recombination rate was reduced, and the photo-Fenton performance was also significantly improved. And the photocurrent of ZnFe2O4/BiOI is more than 27 times that of pure ZnFe2O4. In addition, ZnFe2O4/BiOI can degrade the simulated pollutant RhB 100% within 20min under simulated sunlight. It shows that ZnFe2O4/BiOI binary composite has excellent photo-Fenton properties. In addition, ZnFe2O4/BiOI still maintains a high photo-Fenton ability after three cycles. Therefore, it has potential application prospects of the industrial photodegradation of organic pollutants.

Self-powered high-performance flexible GaN/ZnO heterostructure UV photodetectors with piezo-phototronic effect enhanced photoresponse

The quest and development of optoelectronic sensors with high performance, sustainable, wearable, portable, and maintenance-free operation offers a significant impetus to explore self-powered flexible photodetectors (PDs). Here, a p-GaN/n-ZnO heterostructure-based self-powered and flexible ultraviolet PD is demonstrated by combining laser lift-off of GaN film and hydrothermal synthesis of ZnO nanowires. The device shows a large on/off current ratio (up to 7.36 ×106), outstanding detection sensitivity (6.82 ×1013 Jones), and fast response (6.9/6.4 ms) at 325 nm illumination at a bias voltage of 0 V, also exhibiting a relatively broad spectral response, remarkable reproducibility under thousands of switching cycles, and superior mechanical stability. In addition, since both GaN and ZnO are piezoelectric semiconductor materials, the piezoelectric charges created at two sides of heterojunction interface under an external strain will regulate the separation, extraction and recombination of photo-generated carriers based on the piezo-phototronic effect, resulting in an enhancement of relative responsivity up to 22% with a compressive strain of − 0.48% under UV illumination of 38.4 mW/cm2. This work not only exhibits a self-powered flexible optoelectronic device with potential applications in photo-sensing for artificial skin, optical communication, and self-powered integrated systems, but also provides a strategy to optimize the performance of prospective optoelectronic sensors via the piezo-phototronic effect.

A novel 2D graphene oxide modified \u03b1-AgVO3 nanorods: Design, fabrication, and enhanced visible-light photocatalytic performance

Silver vanadates are promising visible-light-responded photocatalysts with suitable bandgap for solar absorption. However, the easy recombination of photogenerated carriers limits their performance. To overcome this obstacle, a novel 2D graphene oxide (GO) modified α-AgVO3 nanorods (GO/α-AgVO3) photocatalyst was designed herein to improve the separation of photocarriers. The GO/α-AgVO3 was fabricated through a facile in-situ coprecipitation method at room temperature. It was found that the as-prepared 0.5 wt% GO/α-AgVO3 exhibited the most excellent performance for rhodamine B (RhB) decomposition, with an apparent reaction rate constant 18 times higher than that of pure α-AgVO3 under visible-light irradiation. In light of the first-principles calculations and the hetero junction analysis, the mechanism underpinned the enhanced photocatalytic performance was proposed. The enhanced photocatalytic performance was ascribed to the appropriate bandgap of α-AgVO3 nanorods for visible-light response and efficient separation of photocarriers through GO nanosheets. This work demonstrates the feasibility of overcoming the easy recombination of photogenerated carriers and provides a valuable GO/α-AgVO3 photocatalyst for pollutant degradation.

High-efficiency, compressible, and recyclable reduced graphene oxide/chitosan composite aerogels supported g-C3N4/BiOBr photocatalyst for adsorption and degradation of rhodamine B

Photocatalytic technology has received considerable attention due to its advantages of high efficiency, economy and thorough degradation of pollutants, making it the most promising sewage treatment technology. However, the difficulty in recycling usually limits its applications. In our research, we developed a composite aerogel with excellent mechanical properties, photocatalytic properties and recyclability to adsorb and degrade rhodamine B (RhB) dye. In this composite, g-C3N4/BiOBr was loaded on the matrix of rGO and chitosan (CS), with borax as the crosslinking agent. The adsorption experiment showed that the equilibrium adsorption capacity of g-C3N4/BiOBr@CS/rGA aerogels were 3.08 mg/g. The composite photocatalyst of g-C3N4/BiOBr could effectively inhibit the recombination of photo-generated carriers, loaded on the rGO matrix with admirable conductivity, which further improved the photocatalytic performance. The degradation rate of RhB could reach to 94.6% at 180 min under the neutral condition of pH= 7. In addition, the amine group of CS reacted with the carboxyl group of GO to form an amide group, it enhanced the mechanical properties of the aerogels. The compressive strength was 0.152 MPa at 50% strain, and there was basically no decrease after 5 cycles. The composite aerogels exhibited good recycling performance, and the degradation rate was about 80% after 4 cycles.

Formation and textural characterization of size-controlled LaFeO3 perovskite nanoparticles for efficient photocatalytic degradation of organic pollutants

A series of LaFeO3 perovskite nanoparticles (NPs) were successfully formed by a direct sol-gel method involving different citric acid to metal ratios of x (where x = 2–16). The resulted precursors were treated via auto-combustion, followed by calcination at different temperatures (300–700 °C). Size-controlled LaFeO3 NPs were getting smaller down to 18.8 nm at high citric acid ratio, showing relatively high surface area up to 27.6 m2/g . Photocatalytic activity of the formed LaFeO3 NPs was explored for methylene blue (MB) degradation in the absence and presence of 0.5 mM H2O2 under light irradiation. Results showed that variation of citric acid to metal ratio alter the band gap and reduce the photo-generated charge carriers recombination of LaFeO3 NPs. Moreover, the LFC4-500 material (LaFeO3 synthesized using × = 4, and calcined at 500 °C) was the most active photocatalyst in solution at pH = 3 and 0.5 mM H2O2, with the highest efficiency > 99% within 30 min and showed excellent reusability without etching even after several cycles. Significantly, the LaFeO3 NPs characteristics were correlated with their synthesis conditions and the type of interaction with citric acid during initial stages of crystal formation.

Theoretical investigation of electronic and optical properties of the 2D-MoSe2/GaN heterostructure nanosheet

Two-dimensional (2D) metal dichalcogenides have recently fascinated the consideration of researchers due to their exceptional electronic and optical characteristics. Despite this, the higher photo-generated carrier recombination rate constrains their technical utilization. Implementing a promising approach may result in the construction of 2D heterostructures , which may improve photocatalytic activity . This article presents the electronic structure, optical, thermodynamical, and photocatalytic characteristics of MoSe 2 /GaN heterostructures. In 2D-MoSe 2 /GaN, the MoSe 2 and GaN nanosheets interact through the van der Waals forces with a binding energy of −1.72 eV. The electronic structures of the heterostructure confirm that it is a type-II indirect band-gap semiconductor with a band-gap of 1.71 eV. Work function studies revealed that the studied heterojunctions exhibit enhanced photocatalytic activity. Figure : Two-dimensional MoSe2/GaN nanosheet heterostructure. • MoSe2 and GaN sheets interact via vdW forces in the MoSe 2 /GaN heterostructure. • MoSe 2 /GaN band structure reveals a p-type semiconductor by type-II band alignment. • Optical properties are dominating in 100-plane electric polarization. • The workfunction confirms the photocatalytic behavior of the sample.

2D/2D Co-Al layered double hydroxide/TiO2 heterostructures for photoreduction of Cr (VI)

Co-Al layered double hydroxide (LDH)/TiO2heterostructures were synthesized using TiO2 nanobelts by a solvothermal method. X-ray diffraction analysis and morphology observation indicate that layered Co-Al LDH was grown on TiO2nanobelts consisted of anatase and TiO2(B). The phase composition of TiO2nanobelt samples depended on the calcined temperature. The phase composition of TiO2 affected the adsorption ability of composite samples. The pseudo-second-order kinetics model fits for the Cr(VI) ions adsorption kinetics of LDH/TiO2 composite samples. In the case of dark condition, the Cr(VI) removal using composite sample (LT4) was about 45%.In contrast, the Cr(VI) removal of the sample reached up to 100% within 10 min under full solar spectrum irradiation. The excellent performance of the sample can be ascribed to the formation of CoAl-LDH/TiO2 heterostructures consisted of one-dimensional TiO2 nanostructure with mixed anatase and TiO2(B) phases and optimized LDH loading. This heterostructure revealed relatively high stability. The interface of two phases effectively hinders the recombination of photo-generated carriers. In addition, the presence of uniformly distributed CoAl-LDH improved the conductivity and light absorption of the composite sample.

Gas-Phase Fluorination of g-C3N4 for Enhanced Photocatalytic Hydrogen Evolution.

Graphitic carbon nitride (g-C3N4) has attracted much attention because of its potential for application in solar energy conservation. However, the photocatalytic activity of g-C3N4 is limited by the rapidly photogenerated carrier recombination and insufficient solar adsorption. Herein, fluorinated g-C3N4 (F-g-CN) nanosheets are synthesized through the reaction with F2/N2 mixed gas directly. The structural characterizations and theoretical calculations reveal that fluorination introduces N vacancy defects, structural distortion and covalent C-F bonds in the interstitial space simultaneously, which lead to mesopore formation, vacancy generation and electronic structure modification. Therefore, the photocatalytic activity of F-g-CN for H2 evolution under visible irradiation is 11.6 times higher than that of pristine g-C3N4 because of the enlarged specific area, enhanced light harvesting and accelerated photogenerated charge separation after fluorination. These results show that direct treatment with F2 gas is a feasible and promising strategy for modulating the texture and configuration of g-C3N4-based semiconductors to drastically enhance the photocatalytic H2 evolution process.

High temperature hydrothermal etching of g-C3N4 for synthesis of N doped carbon quantum dots-supported CdS photocatalyst to enhance visible light driven hydrogen generation

Herein, we proposed a facile method to synthesize N doped carbon quantum dots (NCQDs) using g-C3N4 as carbon-nitrogen source, and the NCQDs-modified CdS nanocomposite catalysts for photocatalytic water splitting were synthesized by one-step hydrothermal method. The results showed that the NCQDs with a size of 3.2 nm obtained by hydrothermal etching were adsorbed on the surface of CdS particles with a size of 80 nm and induced the regulation of the surface morphology of CdS particles. There was strong interaction between NCQDs and CdS through C-S bond. The introduction of NCQDs in composite catalysts not only increased the photo-absorption performance but also suppressed the recombination of photo-generated carriers, which enabled the photo-generated electrons to transfer to NCQDs effectively and quickly and improved the photocatalytic performance of hydrogen production from water splitting. The composite photocatalysts showed good response to visible light in UV-Vis DRS and the photocatalytic water splitting experiment showed that the photocatalytic hydrogen production activity of composite catalysts was significantly improved under visible light (λ > 400 nm). And the maximum hydrogen production rate reached 2306.1 μmol/g/h, which was about 7 times the amount of unsupported NCQDs sample.

N-doping TiO2 hollow microspheres with abundant oxygen vacancies for highly photocatalytic nitrogen fixation

Photocatalytic fixation of nitrogen to ammonia (NH3) is a green but low-efficiency technology due to the high recombination of photo-generated carriers and poor light absorption of photocatalysts. Generally, the adsorption capacity for N2 and the band position of TiO2 are responsible for bandgap, light-adsorption, and the separation of photocarriers. Therefore, they play crucial roles to improve catalytic activity. Herein, N-doping TiO2 hollow microspheres (NTO-0.5) with oxygen vacancies were synthesized via a hydrothermal method using phenolic resin microsphere as a template. The obtained NTO-0.5 achieves an impressive ammonia yield of 80.09 μmol gcat−1h−1. Oxygen vacancies of NTO-0.5 were confirmed by ESR, Raman, XPS, Zeta potential, and H2O2 treatment for reducing oxygen vacancies. The ammonia yield of NTO-0.5 decreases to 34.78 μmol gcat−1h−1 after reducing oxygen vacancies by H2O2 treatment, which demonstrates the importance of oxygen vacancies. The oxygen vacancies narrow the bandgap from 3.18 eV to 2.83 eV and impede the recombination of photo-generated carriers. The hollow microspheres structure is conducive to light absorption and utilization. Therefore, the synergistic effect between the oxygen vacancies and the hollow microspheres structure boosts the efficiency of photocatalytic nitrogen fixation. After four cycles, the ammonia production yield still maintains at 76.52 μmol gcat−1h−1, meaning high stability. This work provides a new insight into the construction of catalysts with oxygen vacancies to enhance photocatalytic nitrogen fixation performance.