Synergistic Effect Of Pt Research Articles

Synergistic effects of Pt and Y addition in (Ni, Pt)CrAlY bond coat on oxide spallation resistance and growth of interdiffusion zone between bond coat and Ni-based single crystal superalloy

This study shows the beneficial effect of Pt addition to the (β+γ)-NiCrAlY coating. Adding Y in NiCrAl increases oxide growth kinetics but improves spallation resistance. Pt with Y does not change the oxidation rate compared to only adding Y but significantly reduces spallation when cooled to room temperature. Continuous layers of Al2O3 and Cr2O3, along with other oxides such as YAlO3, NiCr2O4, and NiAl2O4, are observed. Moreover, Pt addition reduces the thickness of the interdiffusion zone where Al goes through an uphill diffusion profile, minimizing Al loss and significantly decreasing the growth of deleterious TCP phases.

Oxygen Vacancy Enabled Electronic Structure Engineering of Pt-WO3 Nanosheets toward Highly Efficient BTEX Sensing.

A Pt nanoparticle-immobilized WO3 material is a promising candidate for catalytic reactions, and the surface and electronic structure can strongly affect the performance. However, the effect of the intrinsic oxygen vacancy of WO3 on the d-band structure of Pt and the synergistic effect of Pt and the WO3 matrix on reaction performance are still ambiguous, which greatly hinders the design of advanced materials. Herein, Pt-decorated WO3 nanosheets with different electronic metal-support interactions are successfully prepared by finely tuning the oxygen vacancy structure of WO3 nanosheets. Notably, Pt-modified WO3 nanosheets annealed at 400 °C exhibit excellent benzene series (BTEX) sensing performance (S = 377.33, 365.21, 348.45, and 319.23 for 50 ppm ethylbenzene, benzene, toluene, and xylene, respectively, at 140 °C), fast response and recovery dynamics (10/7 s), excellent reliability (σ = 0.14), and sensing stability (φ = 0.08%). Detailed structural characterization and DFT results reveal that interfacial Ptδ+-Ov-W5+ sites are recognized as the active sites, and the oxygen vacancies of the WO3 matrix can significantly affect the d-band structure of Pt nanoparticles. Notably, Pt/WO3-400 with improved surface oxygen mobility and medium electronic metal-support interaction facilitates the activation and desorption of BTEX, which contributes to the highly efficient BTEX sensing performance. Our work provides a new insight for the design of high-performance surface reaction materials for advanced applications.

Confined Pt and M (M = Fe, Co) nanoparticles on NC with ultralow Pt loading for oxygen reduction reaction

In this work, we have prepared Pt and M nanoparticles on nitrogen-doped carbon catalysts (Pt&M/NC, M = Fe, Co) with an ultralow Pt loading (<3 wt%) from room reduction of Pt and 3d transition metals by sodium borohydride on NC, where NC is firstly from pyrolysis of carbon black together with melamine. In Pt&M/NC (M = Fe, Co), Pt and 3d transition metals are in the individual nanoparticles with the size < 2 nm, where M is conducive to create the spatial confinement effect to anchor Pt nanoparticles. Meanwhile, Pt&M/NC (M = Fe, Co) has more internal defects than those of Pt/NC and M/NC. Owing to the synergistic effect of Pt and M together with NC, electrochemical results show that Pt&Co/NC has the ORR peak potential and half wave potential of 0.863 and 0.840 V vs. RHE, respectively, where they are 0.848 and 0.827 V vs. RHE for Pt&Fe/NC, more positive than that of Pt/NC. The average electron transfer number of Pt&M/NC (M = Fe, Co) is more than 3.8, close to the four-electron transfer way. This work provides a new method to reduce Pt use for ORR catalysts.

NC Loaded PtM Alloy from M-NC with Ultralow Pt Loading for Oxygen Reduction Reaction

Developing low Pt or non-precious metal catalysts for oxygen reduction reaction (ORR) has becoming necessary in recent years. Herein, PtM alloy anchored on nitrogen-doped carbon (PtM/NC, M=Fe, Co) catalyst with ultralow Pt loading (∼1 wt%) is prepared from the simple two-process pyrolysis, namely from C to M-NC then to PtM/NC. The as-prepared PtM/NC (M=Fe, Co) shows an excellent ORR catalytic performance with the peak potential and half-wave potential of 0.901 and 0.870 V for PtFe/NC, 0.868 and 0.845 V for Pt3Co/NC. The ORR on PtM/NC (M=Fe, Co) is a mainly direct 4-electron reaction pathway (3.75–3.90) in alkaline solution. Moreover, they possess good methanol tolerance and stability. Synergistic effect of Pt and M together with N species result in the excellent ORR catalytic activity of PtM/NC (M=Fe, Co). The negative shift of Pt binding energy caused by both lattice contraction and electron orbital coupling from M is beneficial for reducing the d-band center of Pt, weakening the oxygen binding energy and enhancing the ORR intrinsic activity of Pt. The strong interactions between NC and PtM alloy are beneficial for anchoring PtM nanoparticles, promoting the stability of catalyst. This work provides a new strategy for preparing ultralow Pt loading catalysts.

The Oxidation Performance of a Carbon Soot Catalyst Based on the Pt-Pd Synergy Effect

Pt-Pd-based noble metal catalysts are widely used in engine exhaust aftertreatment because of their better carbon soot oxidation performance. At present, the synergistic effect of Pt and Pd in CDPFs, which is the most widely used and common doping method, in catalyzing the combustion of carbon smoke has not been reported, and it is not possible to give an optimal doping ratio of Pt and Pd. This paper investigates the carbon soot oxidation performance of different Pt/Pd ratios (Pt/Pd = 1:0, 10:1, 5:1, 1:1) based on physicochemical characterization and particle combustion kinetics calculations, aiming to reveal the Pt-Pd synergistic effect and its carbon soot oxidation law. The results show that Pt-based catalysts doped with Pd can improve the catalyst dispersion, significantly increase the specific surface area, and reduce the activation energy and reaction temperature of carbon soot reactions, but excessive doping of Pd leads to the enhancement of the catalyst agglomeration effect, a decrease in the specific surface area, and an increase in the activation energy and reaction temperature of the carbon soot reaction. The specific surface area and pore capacity of the catalyst are the largest, and the activation energy of particle oxidation and the pre-exponential factor are the smallest (203.44 kJ∙mol−1 and 6.31 × 107, respectively), which are 19.29 kJ∙mol−1 and 4.95 × 108 lower than those of pure carbon soot; meanwhile, the starting and final combustion temperatures of carbon soot (T10 and T90) are the lowest at 585.8 °C and 679.4 °C, respectively, which are 22.1 °C and 20.9 °C lower than those of pure carbon soot.

Photocatalytic N-formylation of amines with CO2 over Pt-Bi bimetallic decorated CeO2−x

N-formylation of amines with CO2 is a promising approach to high-efficient utilization of CO2 as C1 feedstock, while conventional thermocatalytic processes suffer from harsh reaction condition and intense energy consumption. In this work, photocatalytic N-formylation of amines with CO2 is achieved at room temperature over Pt-Bi/CeO2−x composite catalyst. The Pt-Bi bimetallic sites increase the concentration of surface oxygen vacancies. Furthermore, the synergistic effects of Pt and Bi improve the light absorption capacity, reduce the band gap energy of the photocatalyst and promote the separation of photoinduced charge carriers. Using PhSiH3 as the reducing agent, the conversion of N-methylaniline reaches 100 % after 3 h irradiation in N, N-dimethylformamide solvent with a N-methylformanilide selectivity of 90.8 %. The composite photocatalyst shows promising cycling stability and universality.

Constructing Ni3Se2‐Nanoisland‐Confined Pt1Mo1 Dual‐Atom Catalyst for Efficient Hydrogen Evolution in Basic Media

Constructing efficient and stable catalysts is the key to achieving green hydrogen production through electrolysis of water. Atomically dispersed catalysts have received widespread attention due to their high atomic utilization and catalytic efficiency. Herein, Pt1Mo1 dual‐atom catalysts anchored on the nickel selenide nanoisland (Pt1Mo1/Ni3Se2) are prepared by a two‐step method. It only needs 53 mV to deliver the current density of 10 mA cm−2 in 1 M KOH media, and the mass activity at 200 mV is approximately 4.13 times higher than that of Pt/C. In addition, the Pt1Mo1/Ni3Se2 also exhibits electrochemical stability of nearly 60 h at 20 mA cm−2. It is shown in the studies that the synergistic effect between Pt and Mo atoms enables the migration of electrons around Mo atoms toward Pt, thus realizing charge redistribution. Further density functional theory calculations verify that synergistic effect of Pt and Mo atoms could optimize the adsorption of H*, enhancing the hydrogen evolution reaction activity. Moreover, the Ni3Se2 nanoisland prevents the aggregation of Pt and Mo dual atom, effectively improving the stability of the catalyst. In this work, a nanoisland confined strategy is provided to construct atomically dispersed catalysts with high activity and stability for water splitting.

Facile synthesis of platinum-loaded carbon nanosheets with high specific surface area for efficient CWAO of ammonia nitrogen: A low-cost alternative route for treating ammonia containing wastewater

Deep treatment is an important tool to solve the environmental pollution of ammonia-containing wastewater. Considering the stability and economy of industrial application, we propose a simple and economical synthesis strategy. The procedure is based on the carbonization of citrate at elevated temperatures to synthesize high specific surface area and pore-rich carbon nanoflowers, and carbon nanoflower-loaded Pt catalysts were constructed for the catalytic wet air oxidation (CWAO) of ammonia-containing wastewater. The results showed that the synergistic effect of Pt, edge carbon and carboxyl groups led to the increase of CWAO activity. During the reaction, Pt activated NH3 to put it in a high-energy state, and there was a positive synergistic effect between the oxygen-containing functional groups (carboxyl groups) on the surface of the porous carbon nanoflowers and the edge carbon exposed at the adjacent defect sites, which promoted the activation of O2 and the generation of reactive oxygen species. At 200 °C, the Pt1/PC catalysts showed high activity and hydrothermal stability for CWAO of NH3. The conversion of NH3 was 98.24 % within 4 h, and the selectivity of N2 was 100 %. The total nitrogen (TN) was reduced to below 15 mg‧L−1, which meets the Chinese emission standard for TN in petrochemical industry. Therefore, the novel catalyst proposed in this study effectively solved the problems of complicated catalyst synthesis steps and poor hydrothermal stability in ammonia CWAO studies. The catalyst has potential industrial applications for CWAO of ammonia-containing wastewater.

Effects of Bifunctional Oxygen Catalyst Layer Composition on Unitized Regenerative Fuel Cell Performance

Proton exchange membrane unitized regenerative fuel cells (PEM-URFCs) can generate storable fuel (hydrogen) and oxidant (oxygen) which can then be used to produce power from the same cell. Combining electrolysis and fuel cell modes within the same cell allows PEM-URFCs to have the potential for lower mass, volume, and cost compared with discrete fuel cell and electrolyzer systems. The bifunctional oxygen catalyst layer (BOCL) catalyzes the oxygen evolution reaction (OER) and the oxygen reduction reaction (ORR) at the same electrode, and there are wide potential differences and opposing mass transport phenomena involved within the BOCL when operating in electrolyzer or fuel cell mode. The BOCL composition, structure and morphology significantly affect performance and stability of PEM-URFCs. In our prior work, we showed bimetallic nanoframes provide bifunctional oxygen electrocatalysts with significantly higher activity compared with monometallic structures, evaluated using a rotating disk electrode configuration.1 We will present our investigation of the effects of the BOCL composition, structure and morphology on URFC membrane electrode assemblies (MEAs) prepared using ultrasonic spraying. Catalyst composition and loading were determined to influence URFC performance, and there are tradeoffs between fuel cell performance, electrolyzer performance, and catalyst cost. In addition to the effects of the active catalyst (either Pt for ORR or IrO2 for OER), our work supports the non-catalytically active component influences MEA performance, which is in agreement with our finding of synergistic effects of Pt and IrO2 within rotating disk electrode measurements.1 We are also evaluating the effects of porous transport layers and different operating conditions on URFC MEA performance and durability over repeated cycling. References Godínez-Salomón, F.; Albiter, L.; Mendoza-Cruz, R.; Rhodes, C.P. Bimetallic Two-dimensional Nanoframes: High Activity Acidic Bifunctional Oxygen Reduction and Evolution Electrocatalysts. ACS Appl. Energy Mater. 2020, 3, 2404-2421.

Effect of Different Amounts of Pt on Fe3O4−TiO2 for Photocatalytic H2 Production Under Solar Light

AbstractIn this study, Pt doped Fe3O4−TiO2 photocatalysts were synthesized in two steps; (i) Fe3O4−TiO2 (FT) was prepared by the complex‐assisted vapor thermal (VT) method, (ii) Pt was doped to Fe3O4−TiO2 (FT−Pt) by the polyol method. The effect of different amounts of Pt was investigated for photocatalytic hydrogen production. The absorption spectrum of FT with 5.0 % Pt exhibits a surface plasmon resonance (SPR) peak of ∼420 nm which corresponds to the band gap of 2.95 eV. The FT and Pt doped FT samples showed a less intense photoluminescence (PL) band than TiO2 (T) due to the lower e−/h+ recombination rate. By increasing % wt. Pt in the FT samples, PL intensity was decreased. Thus, Pt plays an essential role to hinder the recombination of e−/h+ pairs. Consequently, FT‐5.0 % Pt showed 144 μmol/g‐cat H2 production rate, just about 3.3 times higher than that of FT photocatalyst; due to the suitable band gap energy and the retarded e−/h+ recombination. Therefore, the synergistic effect of Pt and Fe3O4 is found to be beneficial to decrease the e−/h+ recombination rate thus the photocatalytic activity enhancement was achieved.

Highly active bimetallic Pt–Cu nanoparticles for the electrocatalysis of hydrogen evolution reactions: Experimental and theoretical insight

Improving the activity and stability of Pt-based electrocatalysts is still crucial for hydrogen generation applications. In this study, we investigated the catalytic properties of Cu-doped Pt alloy nanostructures synthesized by the modified polyol method, and compared the performance of PtCu catalyst with that of commercially available Pt/C for the hydrogen evolution reaction (HER) at room temperature. Structural analyses revealed that the PtCu catalysts exhibited fcc-Fm3¯m crystal structure with an average particle size below 5 nm. The HER performance of the catalysts showed overpotential of around −1.0 V (vs. Ag/AgCl) and Pt0.25Cu0.75 and Pt0.75Cu0.25 catalysts exhibited enhanced performance in 1 M KOH. The Pt0.75Cu0.25 catalyst exhibited distinct performance, with the highest mass activity found to be 62.80 mA mg−1Pt. The most active Pt0.75Cu0.25 catalysis for the HER process had the lowest onset potential of 0.989 V and Tafel slope of 35.5 mV dec−1, which were an improvement compared to commercially available Pt/C catalysts. First principle DFT calculations confirmed the stabilities of Pt1Cu3, Pt1Cu1 and Pt3Cu1 compositions as ordered alloy structures. Nudged elastic band method calculations and the d-band model verified the higher catalytic activity of Pt–Cu nanoparticles compared to pure nanoparticles and point out the relevance of a synergistic effect of Pt and Cu atoms on water dissociation. According to DFT calculations, Cu and Pt sites significantly influenced the adsorption of H2O and H, respectively, for splitting water molecules. While the Pt59Cu20 cluster has the highest H2O adsorption energy at the (100) atop site of Cu atoms, H adsorption occurs at the (111) site of Pt atoms.

Gemcitabine drug intercalation with ds-DNA at surface of ds-DNA/Pt–ZnO/SWCNTs/GCE biosensor: A DNA-biosensor for gemcitabine monitoring confirmed by molecular docking study

Herein, a facile and highly sensitive electroanalytical tool for monitoring and quantifying the antineoplastic drug gemcitabine in real sample was provided. In this regard, a novel DNA-biosensor based on Pt-doped ZnO decorated single walled carbon nanotubes (Pt–ZnO/SWCNTs) hybrid nanomaterial modification of glassy carbon electrode (GCE) was fabricated. Ds-DNA (Calf Thymus), as a biological recognition element, was decorated onto nanomaterial-modified GCE via layer-by-layer fabrication strategy to attain ultimate biosensor ds-DNA/Pt–ZnO/SWCNTs/GCE. The characterizations confirmed the successful fabrication of hybrid nanomaterial, as well as the modification of electrode surface by fabricated nanomaterial. The electrochemical impedance spectroscopy (EIS) analysis revealed that the nanomaterial modification of GCE surface enhanced the electrical conductivity thanks to the synergistic effects of Pt–ZnO and SWCNTs structures, thereby boosted the electrocatalytic activity of the resultant biosensor. The electrochemical characterization results showed that the suggested biosensor is capable of detecting gemcitabine in a wide concentration range of 0.01–30.0 μM, with a detection limit of 5.0 nM. The intercalation binding mode of Gemcitabine inside guanine and cytosine rich region of DNA receptor was approved by molecular docking study. The results of the experimental data were well congruent with the molecular docking analysis, which showed that the binding mode of gemcitabine drug with ds-DNA was intercalation.

Nitrogen-Coordinated Cobalt Single Atoms for Achieving Pt with Superhigh Power and Stability in Proton Exchange Membrane Fuel Cells

To achieve widespread implementation of proton exchange membrane fuel cells (PEMFCs), developing efficient electrocatalysts with excellent activity and durability is of great significance. However, it still remains a big challenge to enhance the durability of low Pt catalysts and simultaneously maintain their high activity under PEMFC operation conditions. In this work, an innovative strategy has been proposed to couple nitrogen-coordinated Co single atoms with Pt nanoparticles (NPs) for a superhigh power and stable catalyst in PEMFCs. Due to the strong metal–support interaction and synergistic effect of Pt and Co atoms, the PtNP–Co1NC catalyst shows excellent catalytic activity and durability in both the liquid half-cell and PEMFC operations, achieving a high power density of 1.38 W·cm–2 and superior stability of 6 mV cell voltage loss at 1.0 A·cm–2 after 5000 potential cycles in PEMFC applications, which is better than that of 1.20 W·cm–2 and 16 mV voltage loss for the commercial Pt/C catalyst. Comprehensive investigations reveal that such excellent durability is ascribed to the anchoring effect of Co1–Nx sites with Pt, which strengthen the interaction between Pt and the nanosheet support, thus significantly mitigating Pt NP ripening and agglomeration, and enhancing catalyst stability under challenging PEMFC operation conditions. This work of integration nitrogen-coordinated Co atoms with Pt may cause profound research on a multiscale design of long-term stable electrocatalyst in PEMFC applications.

A facile strategy for incorporation of PtCo alloy into UiO-66-NH2 for cinnamaldehyde hydrogenation

As a material with multifunctional ligands, metal-organic frameworks (MOFs) can effectively regulate the electronic and geometric state of supported metal nanoparticles (MNPs). Herein, a strategy of PtCo alloy incorporated into UiO-66-NH2 hybrid nanoparticles by a facile one-pot solvothermal method was developed. A series of PtCoy@UiO-66-NH2 materials with different Co/Pt ratios were successfully synthesized using CoO as the cobalt source. The obtained PtCo0.80@UiO-66-NH2 exhibited excellent conversion (94.3%) with high selectivity (93.3%) for selective hydrogenation of cinnamaldehyde (CAL) to cinnamyl alcohol (COL). Moreover, the formation rate of COL achieved to 5 mol·gPt−1·h−1 as Co/Pt atomic ratio was higher than 0.41. The synergistic effect of Pt, Co and UiO-66-NH2 was investigated by various characterizations. The results revealed that the Lewis acid CoNx favored the linear adsorption of CO bond, and PtCo alloy enhanced activity and selectivity by lowering the activation barrier for CO bond activation and simultaneously suppressing adsorption of CC bond.

Synergistic Effect of Pt and Dual Ni/Co Cations in Hydrotalcite-Derived Pt/Ni1.5Co0.5AlO Catalysts for Promoting Soot Combustion

In this article, the catalysts of hydrotalcite-derived Ni1.5Co0.5AlO nanosheet-supported highly dispersed Pt nanoparticles (Ptn/Ni1.5Co0.5AlO, where n% is the weigh percentage of the Pt element in the catalysts) were elaborately fabricated by the gas-bubble-assisted membrane--reduction method. The specific porous structure formed by the stack of hydrotalcite-derived Ni1.5Co0.5AlO nanosheets can increase the transfer mass efficiency of the reactants (O2, NO, and soot) and the strong Pt-Ni1.5Co0.5AlO interaction can weaken the Ni/Co-O bond for promoting the mobility of lattice oxygen and the formation of surface-oxygen vacancies. The Ptn/Ni1.5Co0.5AlO catalysts exhibited excellent catalytic activity and stability during diesel soot combustion under the loose contact mode between soot particles and catalysts. Among all the catalysts, the Pt2/Ni1.5Co0.5AlO catalyst showed the highest catalytic activities for soot combustion (T50 = 350 °C, TOF = 6.63 × 10-3 s-1). Based on the characterization results, the catalytic mechanism for soot combustion is proposed: the synergistic effect of Pt and dual Ni/Co cations in the Pt/Ni1.5Co0.5AlO catalysts can promote the vital step of catalyzing NO oxidation to NO2 in the NO-assisted soot oxidation mechanism. This insight into the synergistic effect of Pt and dual Ni/Co cations for soot combustion provides new strategies for reducing the amounts of noble metals in high-efficient catalysts.

Highly efficient Sn-modified Pt/KY catalyst for n-octane reforming: the synergistic effect of Pt in different electronic states

The synergistic effect of Pt in different electronic states induces Sn-modified Pt/KY catalyst with high aromatization ability in n-octane reforming.

Effects of Catalyst Composition, Loading, and Spray Parameters on the Performance of Unitized Regenerative Fuel Cell Membrane Electrode Assemblies

Proton exchange membrane unitized regenerative fuel cells (PEM-URFCs) combine the ability to both produce power (in fuel cell mode) and generate fuel and oxidant (in electrolysis mode) from the same cell. Compared with discrete fuel cell and electrolyzer systems, URFCs provide the potential for lower mass, volume, and cost. The composition and structure of the bifunctional oxygen catalyst layer (CL), which facilitates the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) at the same electrode, significantly affects performance and stability, particularly given the wide potential differences and different mass transport phenomena involved under operation in fuel cell or electrolysis mode. We previously showed bimetallic nanoframes provide bifunctional oxygen electrocatalysts with significantly higher activity compared with monometallic structures, evaluated using a rotating disk electrode configuration.1 Here, we investigated the effects of the oxygen CL composition, loading, and spray parameters on the performance of URFC membrane electrode assemblies (MEAs). Pt black and IrO2 catalysts were combined at different ratios and deposited at different mass loadings. Catalyst layers were sprayed directly onto membranes using an ultrasonic spray system. Within ultrasonically sprayed catalyst layers, higher spray rates resulted in improved fuel cell performance. Higher catalyst loadings improved both fuel cell and electrolyzer performance, but reached a region of diminishing returns at higher loadings. The ratio of the ORR catalyst (Pt) to the OER catalyst (IrO2) modulated the performance in both fuel cell and electrolyzer modes. Different catalyst ratios influence the catalyst utilization at higher loadings. The comparison of URFC performance at same Pt or IrO2 loadings indicates that in addition to the active catalyst itself, the non-catalytically active component influences MEA performance. This result is in line with our previous evaluation of synergistic effects of Pt and IrO2 within rotating disk electrode measurements1 and supports that in addition to the significant effects of catalyst material structure on performance, the electrode structure plays a critical role in fuel cell and electrolyzer performance in URFC MEAs. Repeated switching of URFC MEAs between fuel cell and electrolysis modes indicates that reasonable performance is maintained over the initial cycles within our single cell test configuration. References Godínez-Salomón, F.; Albiter, L.; Mendoza-Cruz, R.; Rhodes, C.P. Bimetallic Two-dimensional Nanoframes: High Activity Acidic Bifunctional Oxygen Reduction and Evolution Electrocatalysts. ACS Appl. Energy Mater. 2020, 3, 2404-2421. http://dx.doi.org/10.1021/acsaem.9b02051

Deposition of platinum on MOF derived NiSx/NCNTs for highly efficient glucose oxidation

Pt/NiSx/NCNTs were successfully obtained by firstly in situ generating Ni/NCNTs from Ni-MOF and then depositing Pt nanoparticles on vulcanized NiSx/NCNTs. Pt/NiSx/NCNTs displayed highly improved catalytic activities for glucose oxidation, which may be due to the synergistic effect of Pt and NiSx on NCNTs. The good sensing performance of Pt/NiSx/NCNTs sensors includes high sensitivity of 465.7 μA⋅mM−1cm−2 (5 μM − 3000 μM) and 148.8 μA⋅mM−1cm−2 (3000 μM − 8000 μM) and lower detection limit (1.67 μM), indicating its good candidate for glucose detection.

Selective Hydrogenolysis of Biodiesel Waste Bioglycerol Over Titanium Phosphate (TiP) Catalysts: The Effect of Pt & WO3 Loadings

Glycerol is an important by-product (biowaste) from biodiesel production. Transformation of glycerol into value-added compounds is critical in improving the overall efficiency of the biodiesel production. In this work, a sustainable and cleaner production of 1,3-propanediol (1,3-PDO) by vapor phase hydrogenolysis of glycerol was performed over titanium phosphate (TiP) supported catalysts by varying the Pt and WO3 loadings (5–20 wt.%). The WO3 promoted Pt modified TiP catalysts were prepared by a simple wet impregnation method and characterized by various analytical techniques in determining the key properties. Furthermore, the catalyst activity and stability were studied under different reaction conditions. The synergistic effects of Pt and WO3 loadings on the final performance of the catalyst has been significant in improving the hydrogen transfer rate. Both Pt and WO3 promotional effects is envisaged the enhanced catalytic properties in conjunction with TiP support acidity. WO3 incorporation increased Brønsted acidity and formed strong interactions with Pt over TiP support. Both Lewis and Brønsted acid sites presented but BAS played a key role in enhancing the 1,3-PDO selectivity in a bifunctional dehydration-hydrogenation reaction mechanism of glycerol. The effect of reaction temperature, contact times and the weight hour space velocity were evaluated. Overall, under optimized reaction conditions, 2 wt.% Pt-10 wt.% WO3/TiP catalyst displayed superior activity with a maximum glycerol conversion of ~ 85% and ~ 51% of 1,3-PDO selectivity achieved at time on stream of 4 h.Graphical

Robust Pt/TiO2/Ni(OH)2 nanosheet arrays enable outstanding performance for high current density alkaline water electrolysis

Herein, we developed a novel and simple strategy to construct Pt-decorated TiO2/β-Ni(OH)2 nanosheet arrays that steadily deliver large current densities in alkaline electrolyte. It is of great interest to find that the versatile role of few-layered Ti3C2 endows the unique growth mechanism of Pt/TiO2/β-Ni(OH)2. It is worth noting that the interconnected array electrode exhibits noticeable hydrogen evolution reaction (HER) performance, achieving ultralow overpotentials of 107, 145 and 184 mV at high current densities of 500, 1000 and 1500 mA cm−2, respectively, which outperforms most reported HER electrocatalysts. It requires only 1.95 V to drive 1000 mA cm−2 towards full water electrolysis along with considerable stability. It is demonstrated for the first time that the synergistic effect of Pt and TiO2/Ni(OH)2 the enhanced HER performance. This work reports a robust nanoarray support for Pt electrocatalyst to break through its intrinsic barrier in alkaline HER and under large current density.