Mn-doped TiO2 Nanoparticles Research Articles

Electrochemical performance of rice grains like high Mn-doped anatase TiO2 nanoparticles as lithium-ion batteries electrode material

Rice grain-shaped high Mn-doped anatase TiO2(TMO) nanocrystals have been fabricated through redox method at room temperature using several simple chemical reagents. The samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy(XPS), scanning electron microscopy(SEM), transmission electron microscopy and High-resolution transmission electron microscopy (TEM & HRTEM). It indicates that the manganese element was successfully incorporated into the anatase TiO2 nanostructure, and the atomic Mn-to-Ti could reach up to 18.2%. We also analyzed the merits and weaknesses of the nanostructured TMO in electrochemistry by dint of some relevant measures. And the cause of influence on the TMO electrochemical properties was briefly discussed.

Unveiling of Mn doped TiO2 nanoparticles for efficient room temperature gas sensing performance

In this study, pristine TiO2 and Mn-doped TiO2 nanoparticles were hydrothermally synthesized at different molar ratios (1, 3, and 5 %). Powder X-ray diffraction (XRD) analysis revealed a pristine anatase phase with a tetragonal structure and an average crystallite size of 7–12 nm. Fourier Transform Infrared (FTIR) spectra identified the presence of metal oxide in the synthesized nanoparticles. The emission peak observed at 647 nm (red emission) due to oxygen bond vacancies, were detected using photoluminescence (PL). The calculated band gap values of pristine and Mn-doped TiO2 were 3.69 and 3.56 eV respectively, from UV-Diffuse Reflectance Spectroscopy. FE-SEM and HRTEM images of the Mn-doped TiO2 nanoparticles revealed agglomerated cubic particles. The magnetic properties of the doped sample exhibited soft ferromagnetic behavior. The N2 adsorption/desorption isotherms unveiled an increased specific surface area of 491.18 m2g−1, accompanied by a pore size measuring 3.6 nm. Mn-doped TiO2 nanoparticles exhibit high gas-sensing properties towards acetone with good sensitivity, low response and recovery times.

Photocatalytic Degradation Mechanism of the Pharmaceutical Agent Salbutamol Using the Mn-Doped TiO2 Nanoparticles Under Visible Light Irradiation.

In the present work, the photocatalytic degradation of salbutamol [2-(tert-butylamino)-1-(4-hydroxyl-3-hydroxymethylphenyl)ethanol] under visible irradiation using Mn-doped TiO2 is investigated. The Mn-doped TiO2 nanoparticles were synthesized by the sol-gel method with ratios of 0.1, 0.2, and 0.3%. Significant characteristics, including the rutile/anatase phases ratio, specific surface area, and band gap energy, were due to the amount of Mn doping; the narrowest band gap energy of 2.80 eV was observed in 0.2% Mn-doped TiO2 with specific surface areas of 89.36 m2/g and 10.87/89.13 of rutile/anatase phases. The investigation involved salbutamol photocatalytic degradation, a kinetic study, and the identification of intermediate compounds. The results indicated that 0.2% Mn-doped TiO2 obtained the best salbutamol removal of 95% under an irradiation time of 180 min. Salbutamol slowly degraded to the intermediate compounds in the first 60 min (k = 0.0088 1/min), and these intermediate compounds were dramatically mineralized to small hydrocarbon fragments and carbon dioxide in the later irradiation times (k = 0.0179 1/min). According to the high-performance liquid chromatography-mass spectrometry (HPLC-MS) results, possible degradation pathways of salbutamol were proposed: 2-(tert-butylamino)-1-(3,4-dihydroxyphenyl)ethanone, 2-(tert-butylamino)-ethanol, and 2-(tert-butylamino)-1-(4-hydroxyl-3-hydroxymethylphenyl)ethanone were initially formed and then transformed to 2-(methylamino)-1-(3,4-dihydroxyphenyl)ethanone, 2-(tert-butylamino)-acetic acid, hydroquinone, and 1-(4-hydroxylphenyl)ethanol, respectively. The mineralization of all intermediate compounds was verified by 90% chemical oxygen demand (COD) reduction, and the effluent contained a relatively low COD concentration of 7.8 mg/L.

Green synthesis of Mn-doped TiO2 nanoparticles and investigating the influence of dopant concentration on the photocatalytic activity

• An environmentally friendly method for preparing photocatalysts to treat organic dyes. • A green synthesis approach is adopted to prepare Mn-doped TiO 2 nanoparticles. • Methylene blue is degraded most efficiently using a 0.05% Mn-TiO 2 catalyst. • 0.1 g L -1 of catalyst is found to remove 86% of Methylene blue after 35 minutes. • The regeneration of the Mn 4+ /Mn 2+ cycle is crucial for photocatalytic activity. A tea plant extract is used in the presence of titanium and manganese sources to synthesize three different concentrations of Mn x Ti 1-x O 2 (x=0.03, 0.05, and 0.1). By substituting Ti atoms for Mn, the lattice of TiO 2 is successfully incorporated with Mn. The degradation of Methylene Blue (MB) in the presence of visible light is used to test the photocatalytic activity of the synthesized samples. Among the Mn-doped TiO 2 samples, the highest degradation ratio is observed for samples with a dopant concentration of 0.05 at%. A dose of 0.1 g L -1 and 5 mM of Mn-TiO 2 is found to remove 86% of MB after 35 minutes of reaction. Mn x Ti 1-x O 2 is critically important for speeding up the MB degradation because of electron transfer between Mn and TiO 2 , and for the regeneration of the Mn 4+ /Mn 2+ cycle on its surface. Optical irradiation of the photocatalytic system under visible light led to higher visible photocatalytic activity than pure TiO 2 . We propose a novel and environmentally friendly method for preparing photocatalysts to treat organic dyes.

Optical, structural and semiconducting properties of Mn doped TiO2 nanoparticles for cosmetic applications

Titanium dioxide (TiO2) nanoparticles, have been routinely used in cosmetic and sunscreen applications, due to their ability to absorb in the UV spectrum. Nevertheless, one of the main disadvantages has been the generation of reactive oxygen species (ROS), especially the hydroxyl radical, upon photoexcitation of titania. In this work, we investigate TiO2 nanoparticles doped with 0.6–0.7% manganese (Mn), based in the more stable rutile polymorph of titania. In particular, while the anatase crystal form has the ability to destroy almost any organic matter under UV illumination, rutile is less photoreactive, and with Mn doping its photoactivity is reduced further. In particular, we study its optical, structural and semiconducting properties via the Seebeck effect and show that the material displays p-type characteristics. This is very significant because it shifts the energy levels with respect to formation of hydroxyl free radicals. This ensures that for Mn doped p-type titania it is not energetically possible for the hole created in the valence band by photoexcitation to create an OH. free radical and this may explain its low photoreactivity. It also means that this material can act as a very effective scavenger for hydroxyl free radicals.

Label-Free Electrochemical Sensor Based on Manganese Doped Titanium Dioxide Nanoparticles for Myoglobin Detection: Biomarker for Acute Myocardial Infarction.

A label free electrochemical sensor based on pure titanium oxide and manganese (Mn)-doped titanium oxide (TiO2) nanoparticles are fabricated and characterized for the sensitive detection of myoglobin (Mb) levels to analyze the cardiovascular infarction. Pristine and Mn-doped TiO2 nanoparticles were synthesized via the sol-gel method and characterized in order to understand their structure, morphologies, composition and optical properties. The structural properties revealed that the pure- and doped-TiO2 nanoparticles possess different TiO2 planes. FTIR studies confirm the formation of metal oxide nanoparticles by exhibiting a well-defined peak in the range of 600–650 cm−1. The values of the optical band gap, estimated from UV-Vis spectroscopy, are decreased for the Mn-doped TiO2 nanoparticles. UV-Vis spectra in the presence of myoglobin (Mb) indicated interaction between the TiO2 nanoparticles and myoglobin. The SPE electrodes were then fabricated by printing powder film over the working electrode and tested for label-free electrochemical detection of myoglobin (Mb) in the concentration range of 0–15 nM Mb. The fabricated electrochemical sensor exhibited a high sensitivity of 100.40 μA-cm−2/nM with a lowest detection limit of 0.013 nM (0.22 ng/mL) and a response time of ≤10 ms for sample S3. An interference study with cyt-c and Human Serum Albumin (HSA) of the sensors show the selective response towards Mb in 1:1 mixture.

Multi-Objective Optimization of Mn-Doped Tio2 Content for Wettability, Printability and Intermetallic Layer of Sac305 Pb-Free Solder Paste on a Cu Substrate

Effects of Mn-doped TiO2 nanoparticles on the wettability, printability and thickness of intermetallic layer of SAC30 on a Cu substrate were studied in this paper. Concentration of Mn-doped TiO2 nanoparticles was varied from 0.05 wt.% to 1[Formula: see text]wt.%. The wettability was evaluated in terms of contact angle of solder on the copper substrate and the printability was measured from the volume ratio of printed solder on the copper substrate to volume of stencil opening. The experimental results showed that 0.10[Formula: see text]wt.% Mn-doped TiO2 led to the lowest contact angle while the printability was decreased with the increase of the added nanoparticles and the thinnest intermetallic layer was found at 0.50[Formula: see text]wt.% Mn-doped TiO2 nanoparticles. Mn-doped TiO2 concentration was then optimized using a desirability function to find optimal values for the three responses. It was found that 0.07[Formula: see text]wt.% was the optimal concentration for the three metrics — wettability, printability and thickness of the intermetallic layer.

Prozac® photodegradation mediated by Mn-doped TiO2 nanoparticles: Evaluation of by-products and mechanisms proposal

TiO2 nanoparticles were efficiently doped with Mn applying microwave-assisted synthesis method. Anatase phase was confirmed by XRD pattern, which did not exhibit the peaks associated with MnOx contamination. Raman spectroscopy showed a displacement of up to 5 cm−1 in the O-Ti-O vibrational mode, suggesting that Ti was replaced by Mn. Oxidation state (Mn3+) was confirmed via high-resolution XPS spectrum of Mn 2p energy level. Incorporation of Mn into the TiO2 network resulted in increased surface area (64.6 m2 g−1), average particle size up to 16 nm, and bandgap reduction of up to 43 %. The photocatalytic properties of the materials were investigated through Prozac® degradation and improvement of up to 14 % (Ti-0.73 Mn) and 26 % (Ti-0.38 Mn) was seen on comparing doped TiO2 versus pure TiO2 during photocatalysis. Furthermore, after Prozac® photodegradation, TFMP was identified as the main by-product while MAEB and PPMA (other by-products) were seen to compete with each other in the degradation mechanism. In addition to the quantitative analysis done for Prozac®, TFMP, MAEB, and PPMA, LC MS-Q-TOF analysis was performed, confirming that in the presence of Mn-doped TiO2, specific by-products were formed, probably due to more oxidizing species being present in this reaction system. The present study has shown unprecedented evidence that the application of TiO2 nanoparticles efficiently doped with Mn promotes Prozac® degradation by specific mechanisms.

Morphology-dependent titanium dioxide nanoparticle-induced keratinocyte toxicity and exacerbation of allergic contact dermatitis.

Titanium dioxide (TiO2) nanoparticles are commonly found in consumer products, such as sunscreens, and human dermal exposures are relatively high. Research suggests potential differences in the toxicity of anatase and rutile crystalline forms of TiO2. Additionally, transition metal dopants are frequently used to enhance physicochemical properties of TiO2, and the toxicity of these nanoparticles are not extensively studied. Therefore, this work examined the keratinocyte toxicity and in vivo skin allergy responses after treatment with 30 nm anatase, 30 nm rutile, or <100 nm Mn-doped TiO2 nanoparticles. After a 24-hour exposure, there were no differences in keratinocyte cytotoxicity; however, Mn-doped TiO2 nanoparticles induced significant in vitro ROS generation and in vivo skin swelling responses in a model of allergic contact dermatitis.

Unusual structural transformation and photocatalytic activity of Mn doped TiO2 nanoparticles under sunlight

Here, Mn doped TiO2 nanoparticles are synthesised through sol-gel technique. After doping 1 and 2 at% Mn, the mixed phase of anatase and rutile is observed, whereas 3 at% Mn doped TiO2, shows pure anatase phase. Particle size of ∼12–15 nm is estimated from TEM showing single crystalline nature evidenced from SAED patterns. Such fine particles are primarily contributes to observed unusual transformation. As a consequence, oxygen vacancies and multiple oxidation states of Mn and Ti are detected through XPS. For the first time, Mn doped TiO2 show 80–100% photocatalytic degradation of dyes, such as MB, RhB and CR, under sunlight in 1 h, which might be regarded as a practical method for the treatment of waste water. The multiple oxidation states of Ti and Mn accompanied with oxygen vacancies reveal ferromagnetism and high degradation rate of organic dyes.

Photocatalytic oxidation of gaseous benzene, toluene and xylene under UV and visible irradiation over Mn-doped TiO2 nanoparticles

The photocatalytic oxidation of gaseous benzene, toluene and xylene (BTX) over un-doped, 0.1 and 1 wt% Mn-TiO2 nanoparticles under ultraviolet and visible irradiation was studied in atmosphere of synthetic air or inert gas. The photocatalytic decomposition efficiency and the oxidation products were determined using a Static Photochemical Reactor coupled with FTIR spectroscopy. BTX underwent efficient decomposition over Mn-TiO2 photocatalysts under UV irradiation, more with oxygen presence and less without oxygen. More important toluene and xylene went substantial decomposition over 0.1 mol% Mn-TiO2 under visible irradiation with oxygen presence. The main final oxidation products in the UV photocatalysis of BTX were CO2, CO and H2O, with CO2 and CO yields 4 and 2 respectively. The conversion percentage of benzene, toluene, and xylene to CO2 were 63.6%, 56.4%, 51.8%, and to CO 29%, 26.5%, 23.2%, respectively. In the visible photocatalysis of toluene and xylene the yields of CO were insignificant. Formation of carbon containing deposits on TiO2 surfaces was observed after extensive UV photocatalysis of toluene and xylene, and such by-products surface coverage may reduce the photocatalytic activity of TiO2 samples. Some aspects of the photocatalytic mechanism were examined.

Microstructure and luminescence properties of ZnO:Mn nano-particles and ZnO:Mn/TiO2 nano-composite synthesized by a two-step chemical method

The present study is determined on the fabrication and the characterization of Mn-doped ZnO (Mn/ZnO), TiO2 nano-particles and ZnO:Mn/TiO2 (Mn–O–Ti) nano-composite. The microstructure and luminescence properties were analyzed by XRD, SEM, TEM, optical reflectance and photo-luminescence. The particle sizes of nano-particles and nano-composites have been varied from 12 to 22 nm. The photo-luminescence measurements of the as-prepared Mn/ZnO nano-particles exhibit broad visible emissions, while the Mn–O–Ti composite samples have yellow emission. The Mn–O–Ti nano-composite exhibits considerably ameliorated photo-catalytic activities for the degradation of methyl orange (MO) under the visible light irradiation. The introduction of Mn/ZnO nano-particles to TiO2 confirm that the internal micro-structure, thus obtained will make the stability of nano-composite allowing an improvement of physical properties and catalytic features of TiO2.

Fabrication of Visible Light-Induced Antibacterial and Self-Cleaning Cotton Fabrics Using Manganese Doped TiO2 Nanoparticles.

Ordinary textiles are very often malodorous and the origin of cross-infection. Their microclimate, consisting of moisture, contaminants, and sweat, provides favorable conditions for microbial growth. Therefore, simple approaches of surface modification using functional materials are widely adopted to introduce antibacterial properties. This study reports a simple and low cost technique that renders cotton fabrics antibacterial. Manganese (Mn)-doped photocatalytic titanium dioxide (TiO2) nanoparticles of ∼150 nm average diameter have been prepared by sol gel and applied on textile fabrics using a silicone binder. The treated fabrics displayed 100% reduction of Staphylococcus aureus (Gram-positive) and Klebsiella pneumoniae (Gram-negative) populations within 120 min under sunlight, demonstrating first order of reduction kinetics. Moreover, the functionalized fabrics demonstrated complete degradation of a methylene blue (MB) dye adsorbed on their surface, under both UV and visible light irradiation, turning them white. A similar effect was observed when the treated fabrics were immersed in a MB dye solution and subsequently irradiated. Here, the cotton fabrics functionalized with Mn-doped TiO2 nanoparticles were able to discolour the dissolved MB dye, demonstrating a water purification effect. In addition, the modified fabrics were resistant to several laundry cycles. Physical properties like mechanical strength, color, breathability, and aesthetic of the treated cotton fabrics remained unchanged. The modified cotton fabrics can be envisioned as antibacterial, antiodorous, and self-cleaning textiles for sports, medical uses, uniforms, fashion, home furnishing, and leisure activities. Finally, the treated textiles were found to be biocompatible.

Structural, optical and weak magnetic properties of Co and Mn codoped TiO2 nanoparticles

The present investigation focuses on the structural properties and magnetic response of Co, Mn and Co-Mn doped TiO2 nanoparticles (within 3% dilute doping) along with their optical and electrical studies. X-ray diffraction (XRD) patterns for all these samples show the formation of tetragonal TiO2 anatase phase with no extra impurity phases. Further, Raman bands at 143 cm−1, 396 cm−1, 516 cm−1 and 639 cm−1 also confirm the anatase phase in these samples. Diamagnetic response has been observed in pure TiO2 nanoparticles. However, room temperature (RT) ferromagnetism has been observed with Co and/or Mn doping which gets enhanced further with codoping of Co ions. The observed ferromagnetism has been attributed to the formation of shallow levels with doping/codoping. The Co and/or Mn-doped TiO2 nanoparticles are referred as diluted magnetic semiconductors due to their combined semiconducting and ferromagnetic response. UV-Vis spectra show the band gap of these samples are in the range of 3.03 eV–3.24 eV and a reduction in band gap is observed after codoping. The temperature dependent electrical conductivity measurements also show an enhancement in conductivity after codoping at RT.

Ultra-sensitive and selective NH3 room temperature gas sensing induced by manganese-doped titanium dioxide nanoparticles

The study of the fabrication of ultra-high sensitive and selective room temperature ammonia (NH3) and nitrogen dioxide (NO2) gas sensors remains an important scientific challenge in the gas sensing field. This is motivated by their harmful impact on the human health and environment. Therefore, herein, we report for the first time on the gas sensing properties of TiO2 nanoparticles doped with various concentrations of manganese (Mn) (1.0, 1.5, 2.0, 2.5 and 3.0mol.% presented as S1, S2, S3, S4 and S5, respectively), synthesized using hydrothermal method. Structural analyses showed that both undoped and Mn–doped TiO2 crystallized in tetragonal phases. Optical studies revealed that the Mn doped TiO2 nanoparticles have enhanced UV→Vis emission with a broad shoulder at 540nm, signifying induced defects by substituting Ti4+ ions with Mn2+. The X-ray photoelectron spectroscopy and the electron paramagnetic resonance studies revealed the presence of Ti3+ and singly ionized oxygen vacancies in both pure and Mn doped TiO2 nanoparticles. Additionally, a hyperfine split due to Mn2+ ferromagnetic ordering was observed, confirming incorporation of Mn ions into the lattice sites. The sensitivity, selectivity, operating temperature, and response-recovery times were thoroughly evaluated according to the alteration in the materials electrical resistance in the presence of the target gases. Gas sensing studies showed that Mn2+ doped on the TiO2 surface improved the NH3 sensing performance in terms of response, sensitivity and selectivity. The S1 sensing material revealed higher sensitivity of 127.39 at 20 ppm NH3 gas. The sensing mechanism towards NH3 gas is also proposed.

Adverse effect of Mn doping on the magnetic ordering in Mn doped TiO2 nanoparticles

Herein, we have examined the role played by non-magnetic Mn on the magnetic properties of TiO2 nanoparticles. The samples display complete paramagnetic behavior at room temperature as well as at 10 K. Paramagnetism might be associated with the presence of isolated magnetic spins of Mn2+ in the system. Observation of negative Curie–Weiss temperature indicates presence of antiferromagnetic interaction in the system. Direct exchange interaction of Mn2+–Mn2+ and antiferromagnetic superexchange interaction of Mn2+ ions via lattice O2− ions contribute to antiferromagnetism. Surprisingly, ferromagnetism appears in pure and Mn doped (0.07 mol) TiO2 nanoparticles on vacuum calcination. Although Mn doped TiO2 displays ferromagnetism, there is a loss in magnetization as compared to the undoped TiO2. It is speculated that low growth temperature during vacuum calcinations might have resulted in amorphous MnO phase separation. This could result in competing ferromagnetic–antiferromagnetic interactions and overall reduction in magnetization. From the results it is evident that TiO2 could be made ferromagnetic by introducing sufficient concentration of oxygen vacancies in the system. Mn doping, however, has an adverse effect on the overall ferromagnetic ordering, as there is possibility of antiferromagnetic d–d exchange interaction of Mn2+ ions as well as possibility of antiferromagnetic manganese oxide phases separation.

Toxicological aspects of photocatalytic degradation of selected xenobiotics with nano-sized Mn-doped TiO2

The toxic effects of two selected xenobiotics, bisphenol A (BPA) and atrazine (ATZ), were evaluated after photocatalytic degradation using nano-sized, Mn-doped TiO2. Undoped and Mn-doped TiO2 nanoparticles were synthesized. The samples were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), UV–vis-diffuse reflectance spectra (DRS), X-ray fluorescence spectroscopy (XRF), and BET surface area. The photocatalytic efficiency of the undoped and Mn-doped TiO2 was evaluated for BPA and ATZ. The toxicity of the synthesized photocatalysts and photocatalytic by-products of BPA and ATZ was determined using frog embryos and tadpoles, zebrafish embryos, and bioluminescent bacteria. Possible toxic effects were also evaluated using selected enzyme biomarkers. The results showed that Mn-doped TiO2 nanoparticles did not cause significant lethality in Xenopus laevis embryos and tadpoles, but nonfiltered samples caused lethality in zebrafish. Furthermore, Mn-doping of TiO2 increased the photocatalytic degradation capability of nanoparticles, and it successfully degraded BPA and AZT, but degradation of AZT caused an increase of the lethal effects on both tadpoles and fish embryos. Degradation of BPA caused a significant reduction of lethal effects, especially after 2–4h of degradation. However, biochemical assays showed that both Mn-doped TiO2 and the degradation by-products caused a significant change of selected biomarkers on X. laevis tadpoles; thus, the ecological risks of Mn-doped TiO2 should be considered due to nanomaterial applications and for spilled nanoparticles in an aquatic ecosystem. Also, the risk of nanoparticles should be considered using indicator reference biochemical markers to verify the environmental health impacts.

Anticorrosion Performance of Electrochemically Produced Zn-1% Mn-Doped TiO2 Nanoparticle Composite Coatings

The Zn-TiO2 composite coatings were electrodeposited on mild steel using sulfate plating bath dispersed with 1% Mn-doped TiO2 nanoparticles. The agglomeration state and charge on the particles in plating condition were analyzed by zeta potential and particle size distribution measurements. The change in microstructure and morphology in composite coatings was analyzed by x-ray diffraction, energy-dispersive x-ray diffraction, and Scanning electron microscopic analyses. The corrosion behavior of the coatings was tested by electrochemical methods such as Tafel polarization and Electrochemical Impedance study. The increased charge transfer resistance with reduced corrosion rate was observed for composite coatings compared to pure zinc coating. The morphology and corrosion behavior of the composite coatings are correlated with pure zinc coating properties.

Structural, optical and photoconductivity of Sn and Mn doped TiO2 nanoparticles

The Sn and Mn doped TiO2 nanostructures were synthesized by sol–gel method. The Sn doped TiO2 nanoparticles exhibit anatase–rutile mixed phase, while the Mn doped TiO2 nanoparticles exhibit anatase phase. The Sn and Mn doped TiO2 nanoparticles are spherical in shape and show tensile strain in the host lattice. The optical band gap for these nanoparticles indicates the red shift. It has been observed that the PL intensity decreases after doping of Sn in TiO2 but it starts increasing with increase in Sn content. The pure TiO2 exhibits all the possible emission bands while Sn and Mn doped TiO2 nanoparticles show blue–green emission bands. The doping behavior of Sn and Mn on crystal phase, particle size, XRD patterns, absorption spectra, photoluminescence and photoconductivity of TiO2 nanoparticles have been described.

Donor–acceptor binding interaction of 1-(naphthalene-1-yl)-2,4,5-triphenyl-1H-imidazole with semiconductor nanomaterials

The dynamics of photoinduced electron injection from 1-(naphthalene-1-yl)-2,4,5-triphenyl-1H-imidazole (NTI) to pristine ZnO, Mn-doped TiO2 and BaTiO3 nanoparticles have been studied by absorption, fluorescence and lifetime spectroscopic methods. Both the absorption and fluorescence results suggest the association between the nanoparticles and NTI. The calculated free energy change (ΔGet) confirms the electron injection from NTI to nano semiconductors. The critical energy transfer distance between NTI and the nanoparticles have been deduced. The emission of NTI is enhanced by pristine ZnO and quenched by Mn-doped TiO2 and BaTiO3 nanoparticles which are likely due to change of LUMO and HOMO levels of NTI on its association with nano semiconductors. The strong adsorption of the NTI on the surface of ZnO nanocrystals is likely due to the chemical affinity of the nitrogen atom of the NTI to the zinc ion on the surface of nanocrystals. Electron injection from photoexcited NTI to the CB(S∗→S++e−CB) is likely to be the reason for the fluorescence enhancement.