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Developing cost-effective electrocatalysts for proton electrolyte membrane fuel cell electrodes has proven challenging because of the difficulty in finding inexpensive alternatives to platinum that...

Nickel is well recognized for its high catalytic activity in hydrogen production and hydrotreating, but it experiences severe deactivation upon coke formation. The development of a nickel-based catalyst that is resilient to deactivation while maintaining its signature high activity is therefore desirable. We demonstrate a simple but effective technique for the synthesis of nickel phosphide catalysts by impregnating nickel into carbonized natural cellulose fibers (NCFs) that naturally contain phosphorus. At a sufficient annealing temperature (1100 °C), the nickel particles react with phosphorus, forming Ni2P and Ni5P4 nanoparticles. Higher annealing temperatures (>1500 °C) promote the formation of single atom nickel, which greatly supplements the catalytic performance. Our nickel phosphide catalyst exhibits a markedly superior activity and stability in the synthesis of hydrogen by C2H2 decomposition and the dry reforming of methane (DRM) compared to the Ni/Al2O3 model catalyst. The sustained activity and stability exhibited by the developed catalyst suggest its promise for other hydrotreating reactions and the hydrogen evolution reaction.

Nanocarbon materials have an important role in future energy storage devices, but their production has a significant energy demand and contributes to pollution. This work introduces a new method to carbonise natural biomass into nanocarbon materials at low temperatures via a simple nickel treatment. The materials obtained are covered homogeneously with nickel nanoparticles, and show excellent electrochemical properties. A material which has a unique structure with micro- and macro-pores is obtained after removal of the nickel nanoparticles, leading to outstanding supercapacitor performance. In addition, we show that activation of the nickel particles converts the material into an effective catalyst for the hydrogen evolution reaction.

The oxidative coupling of methane (OCM) has great potential as a cost-effective pathway to directly convert methane to C2 species such as ethane and ethylene. Although NaW/Mn/SiO2 is one of the most promising catalysts for OCM, an improvement in its catalytic performance is required to achieve high C2 yield. Herein, we show that a relatively simple pyridine treatment of NaW/Mn/SiO2 leads to nitrogen-doping of the active sites, resulting in significantly high CH4 conversion rate while maintaining high C2 selectivity. Various characterisation techniques such as X-ray diffraction analysis, X-ray photoelectron spectroscopy, temperature-programmed reduction analysis, transmission electron microscopy, and density functional theory calculations are employed to understand the effect of N doping on the performance of NaW/Mn/SiO2 for OCM.

Three-dimensionally structured graphitic materials are of interest for electrochemical applications as electrodes and catalyst supports. Many synthetic approaches to these materials require a preformed three-dimensional template and a carbon source, especially when highly crystalline materials are required. In this report, we utilise nickel acetate, which contains both a metal catalyst and a carbon source, as the sole component in the synthesis of both three-dimensional multi-layered carbon and graphene spherical structures (GS) and GS-carbon nanotube hybrid materials (GS-CNT), depending on the annealing procedure. By varying the synthesis conditions of these materials we are able to control the crystallinity of the structures. We show that the rapid introduction of the precursor into the hot zone is a key factor in the formation of the structures. This method demonstrates the utility of cheap metal salts as the sole component of the scalable synthesis of three-dimensional hybrid graphitic materials. We then utilise the novel materials as supports for platinum (Pt) nanocrystals produced using a thermal annealing approach and compare the effect of the carbon support on the active surface area and durability in cyclic voltammetry experiments.

With the development of various energy technologies, much interest is focused on the feasibility and efficiency study of energy devices such as fuel cells, batteries, supercapacitors and water electrolysis systems. Among them, polymer electrolyte fuel cell (PEFC), which convert hydrogen into electric energy with zero emission of pollutants, is one of the most promising environmentally friendly technologies. Despite innumerable studies for more than half a century, degradation of the key component, membrane electrode assembly (MEA), is still a big obstacle for the commercialization of PEFC system. For the high performance and long-term stability of Pt/C electrode catalyst, the agglomeration of Pt particles and dissolution or detachment of Pt particles from carbon support have to be improved. For this purpose, we adopted a new shape of nano-carbon material for the surface modification of Pt catalyst. Graphene has been an attractive two-dimensional carbon allotrope having large surface area and electronic conductivity. Graphene also shows high flexibility and mechanical strength so that it can be used for large number of applications such as flexible display or printable electronics, etc [1-2]. In most cases, people need large-area graphene films with little or no defect for high thermal and electronic conductivity. Also, people need to transfer the as-prepared graphene film for each application. All of these processes are not easy or simple, and they are also labor-intensive processes. However, in the case of catalysis, porous graphene films can be synthesized via very simple one-step process and can be used as effective protective layers for Pt catalysts. In this study, we developed porous graphene films in order to improve the long-term stability of Pt catalysts maintaining the high performance of them. The graphene films were synthesized by single-step vaporization process, where the number of graphene layers and the defects in their structure are manipulated by temperature and composition of the precursors. In this process, the amounts of structural defects, pyridine was simultaneously introduced to the vaporization process, which is much easier and cost-effective compared to the conventional NH3-treatment at high temp [3]. Consequently, our Pt/C catalysts coated with porous graphene films showed similar initial activity compared with the commercial catalysts (Pt 40wt%, Johnson Matthey) showing more than 150% higher long-term stability [4]. [1] A.K. Geim and K. S. Novoselov, Nature Mater. 6 (2007) 183. [2] X. L. Li, G. Y. Zhang, X. D. Bai, X. M. Sun, X. R. Wang, E. Wang and H. J. Dai, Nature Nanotech. 3 (2008) 538. [3] Y. Wang, Y. Shao, D. W. Matson, J. Li and Y. Lin, ACS nano 4(4) (2010) 1790. [4] H. Kim, A. Robertson, S. O. Kim, J. M. Kim and J. H. Warner, ACS nano 9(6) (2015) 5947.

Novel Pt-Co alloyed nanocatalysts are generated via chemical vapor deposition-assisted facile one-pot synthesis. The method guarantees highly monodisperse Pt-Co alloy nanoparticles with precise control of metallic compositions within 1 at%. A significant features is that a perfectly alloyed single-crystal structure is obtained at temperatures as low as 500 °C, which is much lower than conventional alloying temperatures.

Nanoscale materials offer enormous opportunities for catalysis, sensing, energy storage, and so on, along with their superior surface activity and extremely large surface area. Unfortunately, their strong reactivity causes severe degradation and oxidation even under ambient conditions and thereby deteriorates long-term usability. Here superlative stable graphene-encapsulated nanoparticles with a narrow diameter distribution prepared via in situ chemical vapor deposition (CVD) are presented. The judiciously designed CVD protocol generates 3 nm size metal and ceramic nanoparticles intimately encapsulated by few-layer graphene shells. Significantly, graphene-encapsulated Co3 O4 nanoparticles exhibit outstanding structural and functional integrity over 2000 cycles of lithiation/delithiation for Li-ion battery anode application, accompanied by 200% reversible volume change of the inner core particles. The insight obtained from this approach offers guidance for utilizing high-capacity electrode materials for Li-ion batteries. Furthermore, this in situ CVD synthesis is compatible with many different metal precursors and postsynthetic treatments, including oxidation, phosphidation, and sulfidation, and thus offers a versatile platform for reliable high-performance catalysis and energy storage/conversion with nanomaterials.

Chemical vapor deposition (CVD) is used to grow thin films of 2D MoS2 with nanostructure for catalytic applications in the hydrogen evolution reaction (HER). Tailoring of the CVD parameters results in an optimized MoS2 structure for the HER that consists of large MoS2 platelets with smaller layered MoS2 sheets growing off it in a perpendicular direction, which increases the total number of edge sites within a given geometric area. A surface area to geometric area ratio of up to ∼340 is achieved, benefiting from the edge-exposed high-porosity network structure. The optimized thickness of the MoS2 film is determined for maximum performance, revealing that increasing thickness leads to increased impedance of the MoS2 film and reduced current density. The current density of the optimum sample reaches as high as 60 mA/cm2geo (normalized by geometric area) at an overpotential of 0.64 V vs RHE (in 0.5 M H2SO4), with a corresponding Tafel slope of ∼90 mV/dec and exchange current density of 23 μA/cm2geo. The lowered Tafel slope and large exchange current density demonstrate that the high-porosity edge-exposed MoS2 network structure is promising as a HER catalyst.

We report the synthesis of carbon nanowires (CNWs) via chemical vapor deposition using catalytic decomposition of ethanol on nanosized transition metals such as Co, Fe, and Ni. Dip-coating process was used for the formation of catalytic nanoparticles, inducing the growth of CNWs on the surface of the carbon fiber paper (CFP). The liquid ethanol used as carbon source was atomized by an ultrasonic atomizer and subsequently flowed into the reactor that was heated up to a synthesis temperature of 600–700°C. Microscopic images show that CNWs of

Porous carbon was synthesized from natural cellulose fibers and its performance as a catalytic support was investigated for a CO2 reforming of CH4. Ni particles supported on cellulose fibers showed little agglomeration, even after a 168-h reforming reaction, but superior catalytic activity and long-term durability compared to a Ni/Al2O3 model catalyst. One of the reasons for these results was the lower extent of coking originating from the carbonaceous support. Another reason for these results was the high dispersion of Ni particles on the cellulose support, which was caused by the presence of alkaline earth metals such as Ca and Mg in the original structure of the support. Alkaline earth metals in the shape of nanosized particles significantly improved Ni dispersion and the interaction between the Ni particles and the support; they also retarded the agglomeration and sintering of the Ni particles. The cellulose fibers treated with different conditions were characterized by Raman and were observed by scanning and transmission electron microscopy. X-ray diffraction was performed to estimate Ni particle size before and after the catalytic usage. The interaction between the Ni particles and the support was measured by X-ray photoelectron spectroscopy.

Fuel-cell electrode catalysts with improved electrochemical properties have been prepared by dispersing Pt nanoparticles onto carbon nanotubes (CNT) using a chemical vapor deposition (CVD) method. (Trimethyl)methylcyclopentadienyl platinum (MeCpPtMe3) has been used as a Pt precursor in the CVD process and the CVD conditions have been optimized to disperse small Pt particles onto the CNT. Pt particles synthesized by CVD have a relatively uniform size of approximately 1 nm, which is substantially smaller than in the case of a commercial Pt/carbon black catalyst (⩽4.5 nm) prepared by wet impregnation. The dispersion of Pt, estimated by CO chemisorption, is also more than 14% greater than the commercial catalyst with these smaller particles. The electrochemically active surface area (ESA), measured by cyclic voltammetry (CV), and the long-time durability of the surface area of Pt/CNT prepared by CVD are higher than those of the commercial catalyst. Consequently, the single cell performance of the former catalyst is superior to that of the latter one.

A CO-tolerant PtRuxSny/C electrocatalyst, with an optimal x/y ratio of 0.8/0.2, was prepared by selectively depositing Sn on the metallic surface of PtRu0.8/C for use as the anode in a polymer electrolyte membrane fuel cell. The CO tolerance of the catalyst was greater when Sn was added by chemical vapor deposition (CVD) than by a conventional precipitation method because most of the Sn added by CVD was located in the vicinity of Pt and Ru surfaces, on which CO molecules were strongly adsorbed. Accordingly, the bi-functional mechanism of CO oxidation, which involved the migration of oxygenated species from the Sn to the adsorbed CO, was expected to be promoted to greater extents in the catalysts prepared by Sn-CVD than those prepared by Sn-precipitation. On the other hand, the ligand-effect mechanism of CO oxidation, which was facilitated by the Pt-Ru alloy formation, was not much affected by the added Sn because the Pt-Ru alloy remained unchanged, particularly when y ≤ 0.2. Among PtRuxSny/C catalysts prepared by Sn-CVD, one prepared by partially substituting Sn for Ru in the PtRu1.0/C catalyst, e.g., PtRu0.8Sn0.2/C, showed higher CO tolerance than one prepared by simply adding Sn to the PtRu1.0/C catalyst, e.g., PtRu1.0Sn0.2/C, which demonstrated the importance of an optimum x/y ratio in the design of the ternary PtRuxSny/C catalysts.

Sn-promoted Pt-based catalysts were prepared by the chemical vapor deposition (CVD) of Sn on commercial Pt/C and PtRu/C catalysts using Sn(CH3)4 as an Sn precursor. The prepared catalysts showed higher CO tolerance than those prepared by adding Sn using an impregnation (IMP) method. This result was obtained because Sn added by CVD was selectively deposited on the Pt and Ru surfaces, instead of on a carbon support, such that the interfacial contact between Pt and Sn was greater in the Sn-CVD catalyst than in the others, as confirmed by in-situ infrared and X-ray photoelectron spectroscopic observations of the catalysts.

The deactivation of CoMo/Al 2 O 3 in the hydrodesulfurization (HDS) of dibenzothiophene (DBT) was investigated under laboratory conditions that allowed the accelerated deposition of coke on the catalyst. The coke deposition was enhanced at low H 2 pressures and when naphthalene was added to the reaction solution. Characterization of deactivated catalysts by elemental analysis (EA) and temperature-programmed oxidation (TPO) identified two types of carbonaceous species deposited on the catalysts, the reactive and the refractory species. The refractory deposit, or hard coke, was a major contributor to the deactivation and, therefore, the amounts of hard coke present on the catalyst determined the overall activity. A correlation was established in this study between the activity and the amounts of deposited hard coke based on the results of accelerated deactivation treatment. A similar relation was also observed between the two parameters when the catalyst was used in an industrial process for long periods. The above findings suggest that the reaction periods of two different scales, i.e., in laboratory and industrial processes, can be correlated with each other based on the amounts of hard coke when coking is the major mechanism of catalyst deactivation.

Despite the innumerable developments of nanosized and well dispersed noble metal catalysts, the degradation of metal nanoparticle catalysts has proven to be a significant obstacle for the commercialization of the hydrogen fuel cell. Here, the formation of Pt nanoparticle catalysts with a porous graphene envelope has been achieved using a single step low temperature vaporization process. While these Pt-Gr core-shell nanoparticles possess superior resilience to degradation, it comes at the cost of degraded overall catalyst efficacy. However, it is possible to combat this lower overall performance through inclusion of low concentrations of nitrogen precursor in the initial stage of single-step synthesis, inhibiting the formation of complete graphene shells, as verified by atomic resolution aberration-corrected transmission electron microscopy (AC-TEM) imaging. The resultant porous graphene encapsulated Pt catalysts are found to have both the high peak performance of the bare Pt nanoparticle catalysts and the increased resilience of the fully shielded Pt-Gr core-shells, with the optimal N-doped Pt-Gr yielding a peak efficiency of 87% compared to bare Pt, and maintaining 90% of its catalytic activity after extended potential cycling. The nitrogen treated Pt-Gr core-shells thus act as an effective substitute catalyst for conventional bare Pt nanoparticles, maintaining their catalytic performance over prolonged use.

Highly dispersed CoMoS/Al2O3 was prepared by dispersing MoS2 crystallites on Al2O3 by a sonochemical method, followed by the selective deposition of Co on the resulting MoS2 crystallites. The newly prepared catalyst contained larger amounts of CoMoS phase, a known active site for hydrodesulfurization (HDS), than a catalyst prepared by sequential impregnation and, as a result, exhibited a two to three times higher activity than that of the impregnated one for the HDS of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT). The former catalyst promoted hydrogenation (HYD) route to a greater extent than direct desulfurization (DDS) route. Therefore, the extent of activity increase for the new catalyst was larger for 4,6-DMDBT HDS, which proceeds largely via the HYD route, than for DBT HDS, which proceeds largely by DDS.

The performance of MoS 2 /Al 2 O 3 catalysts, prepared by a sonochemical method and containing different amounts of fluorine, was investigated for hydrodesulfurization (HDS), using dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) as model compounds. The activity of sonochemically synthesized MoS 2 catalysts was higher than that of impregnated ones due to the improved dispersion of the Mo species. The addition of fluorine to the catalyst further increased the activity, reaching a maximum at the optimum fluorine content, due to an increase in acidity at the catalyst surface. The optimum amount of fluorine for maximum HDS activity was higher for the sonochemically prepared catalysts than for impregnated ones and, therefore, the activity of the former catalysts can be enhanced by fluorine addition to a greater extent than that of the latter types. The two promoting factors, sonochemical synthesis and fluorine addition, led to an increase in the hydrogenation (HYD) rates, compared to the direct-desulfurization (DDS) rates, in the HDS of both DBT and 4,6-DMDBT. However, the enhancement in overall activity was greater for the HDS of 4,6-DMDBT, which proceeds mainly via the HYD route, than for the HDS of DBT. The above reaction results, obtained using different catalysts, can be explained based on the surface properties of the catalysts, as characterized by X-ray photoelectron spectroscopy (XPS), nitric oxide chemisorption and infrared spectra of adsorbed pyridine.

The effect of fluorine added to NiMo/Al2O3 catalysts on their poisoning by basic (quinoline) and non-basic (carbazole) nitrogen compounds during the hydrodesulfurization (HDS) of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) was investigated. Fluorinated NiMo catalysts had a higher activity than fluorine-free catalysts, and this superior activity of fluorinated catalysts was maintained even after poisoning by nitrogen compounds, as confirmed by NO chemisorption and FTIR spectroscopy. The HDS rate was retarded to a greater extent by quinoline than by carbazole. In the HDS of DBT, the difference between the activities of the two types of catalysts remained constant even when the poisoning was extensive. This is in contrast to the case of 4,6-DMDBT HDS, in which the difference in activity decreased when the catalysts were extensively poisoned. The product distribution changed with poisoning showing a characteristic trend that was dependant on the combination of reactants and nitrogen compounds. In DBT HDS, the hydrogenation (HYD) route was poisoned to a more significant extent than the direct desulfurization (DDS) route by both quinoline and carbazole, and was independent of catalyst fluorination. In the HDS of 4,6-DMDBT, quinoline retarded HYD more than DDS but carbazole retarded DDS more than HYD.

A new type of nanoporous carbon with a large surface area and mesoporosity was prepared and used as a support for a hydrodesulfurization (HDS) catalyst. The overall activity of CoMoS catalysts for the HDS of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) is affected by the type of support used for preparing the catalyst and decreases in the order of CoMo /( nanoporous carbon )> CoMo /( activated carbon )> CoMo / Al 2 O 3 . The surface area of activated carbon is the largest among these three types of supports but is significantly lowered after metal loading during the preparation of the catalyst. On the other hand, the surface areas of the other two supports are largely preserved after metal loading. The intrinsic activity of the catalysts, estimated by dividing the overall HDS rate by the amount of NO adsorbed on the catalyst, shows a trend that is different from that for the overall activity, and follows the order of CoMo /( nanoporous carbon )≈ CoMo / Al 2 O 3 > CoMo /( activated carbon ) . The low intrinsic activity of CoMo/(activated carbon) compared to that of the other two catalysts, particularly in the case of 4,6-DMDBT HDS, is obtained because the diffusion of reactants into the catalyst pores is significantly limited. This is not observed with other catalysts supported on nanoporous carbon and alumina. From the results of this study, we conclude that nanoporous carbon is a promising support for HDS catalysts, compared to conventional supports such as alumina and activated carbon, because it has a large surface area and a high mesoporosity, both of which are beneficial to the preparation of highly dispersed metal catalysts without significant pore blocking due to the dispersed metal particles.

A series of fluorinated NiMo/Al2O3 catalysts containing different amounts of fluorine were prepared and their activity with respect to the hydrodesulfurization (HDS) of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) was compared with that of fluorinated CoMo/Al2O3 catalysts. Fluorine modifies two properties of NiMo/Al2O3 catalysts: metal dispersion and catalyst acidity. In the HDS of DBT, the catalytic activity is enhanced up to 0.5 wt.% added fluorine due to increased dispersion of the metal, and lowered by further fluorine addition because the catalysts lose a significant amount of initial surface area. The hydrogenation of the DBT aromatic ring is enhanced to a greater extent than the hydrogenolysis of the CS bond due to the fluorine addition. In the HDS of 4,6-DMDBT, however, the catalytic activity is enhanced in proportion to the fluorine content up to 5.0 wt.% added fluorine. The hydrogenolysis of the CS bond is enhanced to a greater extent than the hydrogenation of aromatic rings, in contrast to the trend observed in the HDS of DBT. A facilitated migration of methyl groups in the aromatic ring of 4,6-DMDBT due to an increase in the amounts of acidic sites of the catalysts is responsible for the enhanced hydrogenolysis of the CS bond. The optimum fluorine content to yield the maximum amounts of either the direct desulfurization (DDS) or ring-hydrogenated (HYD) products is different depending on the reactants, DBT or 4,6-DMDBT, as well as the catalysts, NiMo/Al2O3 or CoMo/Al2O3. The characteristic reaction results obtained in this study can be explained by considering the relative contributions of the rates of ring hydrogenation and methyl-group migration to product distribution for different cases of reactants and fluorinated catalysts.

Highly dispersed MoS 2 /Al 2 O 3 catalysts containing various amounts of MoS 2 were prepared by the sonochemical decomposition of molybdenum hexacarbonyl in the presence of sulfur and alumina, and tested for the hydrodesulfurization (HDS) of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT). The sonochemically synthesized catalysts exhibit an HDS activity about five-fold higher than that of catalysts prepared by a conventional impregnation method over a wide range of MoS 2 loadings. The difference in HDS activity between the two types of catalysts is large, particularly at high loadings of MoS 2 , because, in the case of the former catalysts, the activity increases with the amount of MoS 2 to the point where the latter is as high as 25 wt.% while, on the latter catalysts, the activity reaches a saturation level when the amounts of MoS 2 are larger than about 15 wt.%. The enhanced HDS activity of the sonochemically synthesized catalysts can be attributed to the improved dispersion of catalytically active species on the support, which is preserved up to high Mo loadings, and the absence of poisoning by sulfur chemisorbed on the catalyst. In both the cases of DBT HDS and 4,6-DMDBT HDS, hydrogenated products are obtained in larger amounts on the sonochemically synthesized catalysts than on the impregnated ones. With respect to the HDS of DBT and 4,6-DMDBT, the latter is enhanced more than the former on the sonochemically synthesized catalysts, which is again due to the high hydrogenation activity of the catalysts.

Pt3Co nanoparticles synthesized by the one-pot chemical vapor deposition (CVD) technique, described by S. O. Kim, H. Kim and co-workers on page 7115. Pt3Co alloyed nanoparticles, illustrated as small planets in space, are synthesized from two different precursor spacecraft, MeCpPtMe3 and CpCo(CO)2. In the image, the silver spheres signify Pt atoms, and the blue spheres represent Co atoms. After both precursor spacecraft land on a carbonaceous planet, they are decomposed and made into Pt3Co small planets releasing small spacecraft of by-products (C5H5, CO2, CH4, and CH3-C5H5). The astronauts perform post-treatment for the perfectly alloyed structure, which corresponds to the thermal treatment in this study.

International audience; A novel QD-peptide complex for detecting HIV-1 protease activity was prepared from simple one step electrostatic interaction. Fluorescence recovery of the pre-quenched QD through fluorescence resonance energy transfer allowed for in vitro assay and live cell imaging of the protease activity in HIV-1 transfected cells, proving the potential for cell-based protease inhibitor screening.

An oligonucleotide modified with Ni-nitrilotriacetate (NTA) was successfully synthesized and used for the stoichiometric functionalization of QDs. This synthetic approach allowed for the facile preparation of DNA–QD conjugates with a defined DNA/QD ratio using well-known Ni–histidine coordination chemistry. A FRET based DNA–QD nanoprobe was prepared using this method highlighting the great potential of this synthetic strategy.

A series of fluorinated NiMo/Al2O3 catalysts containing different amounts of fluorine were prepared and their activity with respect to the hydrodesulfurization (HDS) of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) was examined. The addition of fluorine modified two properties of the catalyst, namely the dispersion of metal and the acidity of the catalyst. In the HDS of DBT, the catalytic activity increased with added fluorine up to 0.5 wt.%, and then decreased with further fluorine addition due to the decrease in the surface area of the catalyst. In the HDS of 4,6-DMDBT, catalytic activity increased in proportion to the fluorine content up to 5.0 wt.%. This is possibly due to the increased surface acidity that results from the addition of fluorine.

A new binding strategy of linking quantum dots (QDs) to magnetic nanoparticles (MNPs) using DNA interaction with metal coordination bonding was developed. Platinum was selected for binding QDs to DNA. This novel self-assembled nanoconjugate would be a new probe for diagnosing a specific disease more accurately with its double modalities, fluorescence and magnetic property.