Palladium Metal Research Articles

APPLICATION OF SQUARE WAVE POTENTIAL REGIME TO ELECTRO REDUCTION OF CO2 IN ETHANOLAMINE INTO ETHYL CARBAMATE BY PALLADIUM ELECTRODE

Electrochemical reduction of the CO2 present in 0.1 M Ethanolamine (EA) aqueous solution at Palladium metal electrodes for the synthesis of ethyl carbamate (CH3CH2OC(O)NH2) is investigated. The application square wave potential regime of the carbon dioxide in (EA) to be reduced to an organic product. In addition to identifying optimal conditions for CO2 electrocatalysis reduction by the square wave potential regime, the potential value was between - 1.0 to 0.4 V with 1.4 V amplitude, the time of reaction was 4 hours and the frequency was 100 Hz. We have carried out reactions at various pH levels and different voltages in an alkaline environment to ensure optimal conditions for the production of ethyl carbamate. The palladium catalysts electrode has demonstrated high CO2 electro-reduction activity to the organic compound. The organic product was analyzed by cyclic voltammetry, NMR, UV spectrometry, FT-IR spectroscopy, TGA, and MS. The results suggest the reduction of CO2-saturated in 0.1 M ethanolamine to ethyl carbamate, C2H5OCONH2. The Faradaic Efficiency and current density of electro-convert CO2-saturated in ethanolamine to ethyl carbamate are 93% and 71 mA cm−2, respectively

Research progress on low-concentration methane oxidation using palladium-based catalysts

There is low concentration (0.05% to 0.5%) of CH4 leakage in marine natural gas engine exhaust. It is difficult to capture and utilize low concentration CH4 because of its stable chemical structure and high ignition temperature. Catalytic oxidation is the main method to remove low concentration CH4 from tail gas. The noble metal palladium (Pd) is the best catalytic material for the complete oxidation of low concentration CH4. In this paper, the main research progress of Pd-based catalysts is reviewed for their low-temperature activity, reliability and development cost. Initially, the impact of Pd particle dimensions and valence distribution, Pd dispersion, carrier identity and strong metal-carrier interaction (SMSI) on the catalyst's methane oxidation activity was elucidated. Then, the mechanism of methane oxidation on the surface of Pdbased catalysts is summarized; In addition, the deactivation mechanisms of Pd-based catalysts, such as high temperature sintering, water poisoning and sulphur poisoning, are described in detail. In conclusion, the major hurdles encountered in achieving full oxidation of methane at low concentrations are outlined, along with the future development direction for methane oxidation catalysts. Additionally, strategies to enhance the performance of Pd-based catalysts are briefly suggested. The modified Text maintains a clear, professional, and concise style with minimal changes.

Negative differential resistance based on phase transformation.

The negative differential resistance (NDR) device is attracting attention because of its broad potential application in neuromorphic computing and non-volatile memory. However, only a limited range of materials show NDR and, therefore, there is less choice in material selection for NDR devices. Considering this issue, we here demonstrate a novel current controlled NDR device based on phase transformation. To the best of our knowledge, this report is the first experimental demonstration that NDR can be induced by phase transformation. We believe that the impact of this demonstration is very large, as phase transformation is the most common phenomenon in materials and consequently most materials can be reconsidered as possible candidates for NDR devices. The prototype NDR device is constructed using hydrogen absorbing metal palladium (Pd) thin-wire and the phase transformation from metal-hydride to metal is employed for the demonstration. The observed NDR property shows a strong dependence on the current sweep speed. Also, it exhibits no current polarity dependence. Therefore, the NDR device based on phase transformation is significantly different from typical NDR devices such as tunnel diodes and memristors. The prototype NDR device has been found to be very useful for evaluating the hydrogen storage properties of metals. The advantage of this analysis method is that the storage properties can be acquired just by sweeping the applied current. This demonstration offers novel directions for both the development and utilization of NDR devices.

Palladium(II) extraction from acidic chloride media using an ionic liquid-based aqueous two-phase system (IL-ATPS) in the presence of dipotassium hydrogen phosphate salting-out agent and reductive stripping with hydrazine hydrate to recover palladium metal

Aqueous two-phase systems (ATPSs) based on ionic liquids (ILs) are efficient and green extraction systems. In this study, ATPSs consisted of three hydrophilic imidazolium-based ionic liquids ([C4mim]Br, [C6mim]Br, and [C8mim]Br) with phosphate, which were employed for Pd(II) extraction in acidic solutions. The obtained results showed that IL-ATPSs exhibited excellent Pd(II) extraction performance in acidic media, and Pd(II) was concentrated into ionic liquid rich upper phase. Palladium(II) extraction efficiencies of the three imidazolium-based ILs in acidic media were >98%, and the order of extraction efficiencies was: [C4mim]Br > [C6mim]Br > [C8mim]Br. Palladium(II) concentrated in IL-rich phase was recovered via direct reduction with hydrazine hydrate. Fourier transform infrared spectrometer (FT-IR) and mass spectrometry characterization indicated that Pd(II) migration into IL-rich phase followed an ion-exchange mechanism. Furthermore, transmission electron microscopy showed that “oil-in-water” micelles were formed during Pd(II) extraction.

Electronic effects of amine-imine nickel and palladium catalysts on ethylene (co)polymerization

A series of bis-(aryl)-amine-imine nickel and palladium complexes with electron-donating (OMe), H, and -withdrawing (F and Br) groups at the para-aryl position were synthesized and characterized to probe the ligand electronic effects on homo- and copolymerization of ethylene. The influences of electronic perturbations on complex synthesis, polymerization property, and polymer microstructure were investigated systematically. The electronic effects of para-substituents were verified by Hammett constants and topographic steric maps of nickel and palladium complexes. Electron-rich ligands had stronger complexation ability to the nickel and palladium metal, thereby facilitating the synthesis of nickel and palladium complexes. Ethylene polymerizations at different temperatures showed that electron-deficient amine-imine nickel and palladium catalysts were more active than electron-rich analogues at low temperatures while the reverse trend was observed at high temperatures. The electronic effects of para-substituents affected polyethylene molecular weight, but had little influence on the branching density of highly branched polyethylenes. Copolymerization of ethylene and methyl acrylate (MA) using palladium catalysts demonstrated that the electron-donating group promoted copolymerization performance, and was favorable for direct insertion of MA to produce main-chain MA unit. Electronic effects of amine-imine nickel and palladium catalysts on ethylene polymerization were comprehensively summarized to electronic perturbations on the metal electrophilicity and the thermal tolerance of catalyst.

STUDY OF THE PROCESS OF CARBONIZATION OF POWDERED CELLULOSE GRANULES IMPREGNATED WITH AgNO3 AND Pd(NO3)2

A comparative study of the process of carbonization of powdered cellulose granules and powdered cellulose granules impregnated with silver and palladium nitrate salts was carried out. The process was carried out in the temperature range 200–600 °С. The influence of the presence of metals on the course of carbonization of powdered cellulose and the features of the reduction of silver and palladium during carbonization were studied by IR spectroscopy and X-ray phase analysis. It has been established that the presence of silver in powdered cellulose does not affect the yield of carbonized material. The presence of palladium in powdered cellulose leads to the fact that the yield of carbonizate in the temperature range of 300–600 °C is reduced relative to the yield of carbonizate simply from powdered cellulose. It has been established by IR spectroscopy that impregnation with salts and subsequent drying at 90 °C of powdered cellulose granules leads to the appearance of carboxyl groups in it, which are not observed in unimpregnated powdered cellulose. With an increase in the heat treatment temperature to 200 °C, the amount of these groups in the silver-containing material increases sharply, while in the palladium-containing material it remains unchanged. A significant increase in the number of C=O groups in the palladium-containing material begins at 300 °C. The increased relative content of C=O groups in the metal-containing material is also preserved in the temperature range of 300–500 °C. The presence of metals in powdered cellulose at pyrolysis temperatures of 300–500 °C leads to a decrease in the content of C=C groups in the carbon matrix relative to methylene (methine) groups. At 600 °C, the carbon matrix of all coals is completely carbonized. X-ray diffraction analysis recorded the appearance of metallic silver and palladium in metal-containing coals at a temperature of 300 °C As the carbonization temperature increases, the content of crystalline Ag(0) and Pd(0) in coals increases. No other forms of silver and palladium are found in the temperature range of 300–600 °С. Testing of metal-containing coals in a model reaction of hydrogen peroxide decomposition showed: in silver-containing carbonizates, the availability of silver particles for H2O2 increases due to an increase in the pyrolysis temperature; in Pd/C, an additional factor that increases the availability of metal particles is the interaction of palladium with carbonizate during pyrolysis.

Nano-porous ruthenium-palladium and ruthenium-platinum alloys and their application as hydrogenation catalysts

Nano-alloys of platinum or palladium attract considerable attention in several catalytic applications. Specifically, nano-porous alloys of these metals serve as catalysts or gas adsorbents. Still, preparing such nano-porous alloys with precise and well-controlled metal composition is considered a synthetic challenge. Previous studies have shown a new approach for the fabrication of nano-porous metals and alloys with controlled compositions through the chemical reduction of metal complex salts. In this work, we obtained two bi-complex salts as precursors for Ru-Pd and Ru-Pt alloys. Single crystals of these salts were also obtained and structurally characterized using X-ray crystallography. Then, using the mentioned procedure, the following nano-porous metallic materials were prepared: Ru2Pd3 and Ru2Pt3 alloys, pure ruthenium, platinum, and palladium metals. Powder X-ray diffraction analysis determined the crystalline phases of these metallic materials. High-resolution scanning electron microscopy indicated that they assemble as clusters of interconnected nanoscale metallic ligaments separated by pores of similar dimensions. Each cluster preserves the microscale morphology of its salt precursor. Energy-dispersive X-ray spectroscopy measurements enabled the determination of the precise molar ratio between the two metals within the salts and alloys. Focused ion beam tomography enabled the 3D structural representation of the metals and alloys and the determination of their porosity and specific surface areas using geometrical analysis. All the metallic materials acquired more than 60% porosity and more than 50 m2/g of specific surface area. Specifically, Ru2Pd3 alloy acquired the highest values of ∼91% porosity and a surface area of 386 m2/g. The nano-porous metals and alloys exhibit high selectivity in the catalytic hydrogenation of phenyl-acetylene compared to other non-porous commercial catalysts, implying that their structure improved the selectivity. In addition, the alloys showed high conversions and overall high yields in the same reaction, specifically compared to the pure metals. Subsequently, these results support and extend our previous research and suggest a class of palladium or platinum nano-porous alloys that may serve as new and promising catalysts.

Construction of defects-rich TiO2-supported Pd catalyst for phenol hydrogenation with ball-milling process

An active catalyst Pd/TiO2(M) for phenol hydrogenation to cyclohexanone was constructed via a ball-milling process. This mechanical process avoids the thermal reduction in hydrogen atmosphere and creates oxygen vacancies on TiO2, which prevents the oxide support encapsulating active metal palladium due to the strong metal-support interaction(SMSI) but improves the catalytic performance of palladium. Under atmospheric hydrogen generated by electrolyzingwater, phenol can be hydrogenated to cyclohexanone selectively. Characterizations, control experiments and DFT calculations reveal that surface defective structures of Ti3+-Ov can stabilize Pd nanoclusters and promote the formation of electron-rich Pd. This kind of electronic metal-support interaction facilitates the dissociative adsorption of phenol, so that Pd/TiO2(M) exhibits outstanding catalytic activity and selectivity for phenol hydrogenation to cyclohexanone.

Investigation of the Plasmon-Activated C-C Coupling Reactions by Liquid-State SERS Measurement.

The implementation of plasmonic materials in heterogeneous catalysis was limited due to the lack of experimental access in managing the plasmonic hot carriers. Herein, we propose a liquid-state surface-enhanced Raman scattering (SERS) technique to manipulate and visualize heterogeneous photocatalysis with transparent plasmonic chips. The liquid-state measurement conquers the difficulties that arise from the plasmon-induced thermal effects, and thus the plasmon based strategies can be extended to investigate a wider range of catalytic reactions. We demonstrated the selection of reaction products by modulating the plasmonic hot carriers and explored the mechanisms in several typical C-C coupling reactions with 4-bromothiophenol (4-BTP) as reactants. The real-time experimental results suggest brand new mechanisms of the formation of C-C bonds on plasmonic metal nanoparticles (NPs): the residue of 4-BTP, but not thiophenol (TP), is responsible for the C-C coupling. Furthermore, this technique was extended to study the evolution of the Suzuki-Miyaura reaction on nonplasmonic palladium metals by establishing the charge transfer channels between palladium and Au NPs. The cleavage and formation of chemical bonds in each individual reaction step were discerned, and the corresponding working mechanisms were clarified.

Study of an interesting interplay between thiourea and 4,6-dimethylpyrimidine-2-thiol with palladium(II) phosphine substrate

Treatment of [PdCl2(dppe)] with one equivalent of thiourea yielded a partially substituted complex [PdCl(dppe){SC(NH2)2}]Cl (1a) whereas the compound [Pd(dppe){SC(NH2)2}2]2+ (1b) was obtained on performing the same reaction with two equivalents of thiourea. The reaction between [PdCl2(dppe)] and two equivalents of the sodium salt of 4,6-dimethyl pyrimidine-2-thiol resulted a cis configured complex [Pd{2-SC4H(4,6-Me)2N2}2(dppe)] (2). In the same pattern the reaction of [PdCl2(dppe)] with 4,6-dimethylpyrimidine-2-thiol, triethyl amine and thiourea in 1:1:1 mol ratio afforded a mononuclear heteroleptic complex [Pd{2-SC4HN2(4,6-Me)2}(dppe)]{SC(NH2)2}]Cl (3). All the reported complexes were characterized by elemental analyses, NMR (1H, 13C{1H},31P{1H}), IR, UV-vis spectroscopy. The molecular structure of complex [Pd{2-SC4HN2(4,6-Me)2}(dppe)]{SC(NH2)2}]Cl (3) was established through single crystal X-ray diffraction and showed the distorted square planar geometry around the palladium metal centre.

Graphene supported Pd–Cu bimetallic nanoparticles as efficient catalyst for electrooxidation of methanol in alkaline media

Interfacing non-noble metals with noble metal is considered to be the best strategy to balance efficient adsorption and corresponding electrochemical oxidation of fuel relevant for fuel cell reactions. Herein, copper is interfaced with palladium and deposited onto a reduced graphene oxide (RGO) support by employing a simple one-pot chemical reduction using combined advantages offered by l-ascorbic acid and ethylene glycol. Morphological features and elemental composition of Pd–Cu bimetallics on RGO are assessed by transmission electron microscopy (TEM) and energy dispersive X-ray analysis (EDX). The results revealed presence of well-dispersed Pd–Cu particles with an average particle size from 4 to 6 nm on RGO supports (Pd–Cu/RGO). From X-ray photoelectron spectroscopy (XPS) analysis it is understood that Pd–Cu/RGO catalyst owns metallic palladium surface state with a small fraction of CuO or Cu2O species. Methanol electro-oxidation reaction (MOR) is carried out in nitrogen-saturated solution containing KOH (1 M) + CH3OH (1 M) at room temperature on Pd–Cu/RGO, Pd/RGO and Pd/C commercial catalyst. Electrochemical activity descriptors suggest that compared with Pd/RGO and commercial Pd/C (20 wt%), bimetallic Pd–Cu/RGO exhibited 2.1 and 4.0 times higher Jmass, respectively indicating the advantage of interfacing copper with palladium in improving the kinetics of methanol electro-oxidation. The simple synthesis strategy demonstrated here is convenient to extend to fabricate other metallic particles with controlled particle sizes for fuel cell catalytic applications.

Molecular docking, synthesis and antimicrobial evaluation of metal complexes with Schiff base

The appearance of resistant bacteria was found to reduce the efficiency of antimicrobial therapies with the current antibiotics, thereby increasing the need for more efficient drugs for the treatment of infections. A microbial infection affects tremendously to the human health and antimicrobials are one of the mainly successful forms of chemotherapy which saves the human population from the risk of infectious diseases. In this regard, the present study involves synthesis of transition metal complexes have often shown the immense antimicrobial activity. In this article, metal complexes were synthesized using different metals such as of Zn(II), Hg(II), Pt(II) and Pd(II), using Schiff’s base derived from amino and carbonyl ligand. All the synthesized compounds were characterized using IR, NMR, and mass spectral data and also by UV–visible spectra, molar electric conductance, magnetic susceptibility and thermal studies. Moreover, the antimicrobial activities of metal complexes were demonstrated using both gram negative and gram positive bacteria. The synthetic series of title compounds 6a-d, the compounds 6c and 6d with platinum and palladium metal were found to be active. The complex 6c has shown excellent antimicrobial activity and the result was also confirmed by molecular docking.

Designer-length palladium nanowires can be templated by the central channel of tobacco mosaic virus nanorods

We have developed methods for the templated synthesis of palladium nanowires (Pd NWs) within the central channel of tobacco mosaic virus (TMV) nanorods of various lengths. We show that uniform 4 nm diameter Pd NWs can be produced by selective growth within these channels by including the capping reagent, poly(vinyl-pyrrolidone) (PVP30K) and reducing the metal precursor to metallic palladium with ascorbic acid. The length of the Pd NWs can be controlled either by varying the length of the nanorod templates and/or through alterations to the reaction conditions. We have also demonstrated bimetallic gold (Au)-palladium (Pd) in-situ metallization of TMV nanorods resulting in the production of Pd NWs 6 nm gold nanoparticles attached to their ends. The materials produced have many potential applications in the construction of nanoscale devices.

Recovery of Palladium Metal with High Purity by Selective Reduction from Inorganic Acid Leaching Solutions of Cemented Zinc

A small amount of Pd(II) present in spent electroplating solutions is concentrated by cementation. In this work, a process was developed to recover pure palladium metal by selective reduction from the hydrochloric and the sulfuric acid leaching solutions of cemented zinc. For this purpose, hydrazine and ascorbic acid were employed as reducing agents and the effect of several variables such as the acidity of the leaching solutions, molar ratio of reducing agents to Pd(II), reaction time and temperature was investigated. Since neither of the reducing agents can reduce Pd(II) from strong acidic solutions, it was necessary to decrease the acidity of the leaching solutions by dilution with distilled water. Our results indicated that it was possible to recover Pd metal with high purity by selective reduction after diluting the hydrochloric and sulfuric acid leaching solutions of cemented zinc with distilled water. When the molar ratios of the reducing agents to Pd(II) were the same, the reduction percentage of Pd(II) from the sulfuric acid solution was higher than that from the hydrochloric acid solution, due to the much higher complex formation constant of PdCl42- than Pd(SO4)22-. The reduction of Pd(II) by hydrazine occurred within 15 mins at room temperature, while a higher temperature (60 oC) and longer reaction time (1h) were necessary to reduce Pd(II) with ascorbic acid. The reduction of Pd(II) from sulfuric acid solution was more efficient than from hydrochloric acid solution. It was possible to recover Pd metal with high purity from the leaching solution of cemented zinc using the reduction method.

Palladium Nanoparticles Entrapped In a Hydrogen Bonded Crystalline Organic Salt Matrix as a Selective Heterogeneous Reduction Catalyst

Hydrogen bonded crystalline organic salt matrix encapsulates Pd nanoparticles and makes them selective non-pyrophoric catalysts towards reduction of carbon – carbon triple bonds, inhibiting simultaneous C=O reduction. The comparison of the catalytic performance with Pd/C was carried out to show similar catalytic activity of both catalysts towards C=C bonds.

Labor rate setting as a framework for enhancing efficiency of mining industry

Production engineering in mines of the Norilsk Division of Norilsk Nickel is experiencing considerable modification. Under conditions of continuous retrofit, production improvement and digitalization and unmanned machinery phase-in, the efficient labor management is a prerequisite of production in a transition period. It is emphasized that the Company’s top managers pay peculiar attention to the primary pitch of the production chain—exploration and extraction of rich ore to be concentrated later on and sent to smelting of nonferrous metals (palladium, nickel, platinum copper, as well as silver and gold). The increase in available ore reserves and the gain in production output are amongst the top priority trends of advancing the Norilsk Division of the Company. The article describes the labor rate setting systems adopted at Norilsk Nickel’s Polar Division and generalizes the experience gained in labor rate setting in the mining industry. The photo chronometry observations are illustrated, and the structure of the work time expenditures and losses is analyzed. The elaborated local regulatory documentation enabled a precision computation of labor force as per the actual labor conditions, labor management and occupational safety at a specific production unit. Labor rate setting almost always entails organizational changes—adjustment of operating regime, shift planning, etc., and is often a catalyzer of innovations to be introduced. Furthermore, labor rate setting enables planning, budgeting and real-time management of operations toward meeting strategic challenges in the today’s business environment.

Palladium Decorated, Amine Functionalized Ni-, Cd- and Co-Ferrite Nanospheres as Novel and Effective Catalysts for 2,4-Dinitrotoluene Hydrogenation.

2,4-diaminotoluene (TDA) is one of the most important polyurethane precursors produced in large quantities by the hydrogenation of 2,4-dinitrotoluene using catalysts. Any improvement during the catalysis reaction is therefore of significant importance. Separation of the catalysts by filtration is cumbersome and causes catalyst loss. To solve this problem, we have developed magnetizable, amine functionalized ferrite supported palladium catalysts. Cobalt ferrite (CoFe2O4-NH2), nickel ferrite (NiFe2O4-NH2), and cadmium ferrite (CdFe2O4-NH2) magnetic catalyst supports were produced by a simple coprecipitation/sonochemical method. The nanospheres formed contain only magnetic (spinel) phases and show catalytic activity even without noble metals (palladium, platinum, rhodium, etc.) during the hydrogenation of 2,4-dinitrotoluene, 63% (n/n) conversion is also possible. By decorating the supports with palladium, almost 100% TDA selectivity and yield were ensured by using Pd/CoFe2O4-NH2 and Pd/NiFe2O4-NH2 catalysts. These catalysts possess highly favorable properties for industrial applications, such as easy separation from the reaction medium without loss by means of a magnetic field, enhanced reusability, and good dispersibility in aqueous medium. Contrary to non-functionalized supports, no significant leaching of precious metals could be detected even after four cycles.

Synthesis, structural and exploration of non-covalent interactions of the palladium complex with the crystalline water molecule: A comprehensive quantum chemical approach

A Schiff base ligand, N'-((2-hydroxynaphthalen-1-yl)methylene)-3-phenylpropanehydrazide (L) and its palladium(II) complex [Pd(L)Cl] were synthesized and characterized by FT-IR, SEM, EDAX, and UV–visible and single crystal X-ray diffraction analysis.The crystal structure shows distorted square-planar, where the palladium(II) metal atom is bonded to two oxygen atoms in the equatorial position whereas a nitrogen and chlorine atom along the axial position in a tetradentate monoanionic [O1, O2, N1, Cl1] fashion resulting in the formation of five and six membered chelate rings. The crystal structure is supported by intramolecular NH…O and OH…Cl hydrogen bonds, CH…Cl, NH…O, CH…π and π…π intermolecular secondary interactions resulting in the supramolecular architectures. The 3D description of the intermolecular interactions are quantified using the Hirshfeld surface analysis. Density functional theory (DFT) calculations were performed to obtain the optimum geometry structures using the wB97XD functional. The natural bond orbital (NBO) analysis showed that the metal ion coordinates to the ligands through electron donation from lone pairs on nitrogen and oxygen atoms to the d orbitals of the metal ion. The topology analysis of the electron density by means of the natural bond orbitals (NBO), quantum theory of atoms in molecules (QTAIM), noncovalent index (NCI), and electron localization function (ELF) have revealed valuable information regarding the nature of interactions and the results are in good agreement with the structural analysis results.

Biosynthesized Gold, Silver, Palladium, Platinum, Copper, and Other Transition Metal Nanoparticles.

Nanomedicine is a potential provider of novel therapeutic and diagnostic routes of treatment. Considering the development of multidrug resistance in pathogenic bacteria and the commonness of cancer, novel approaches are being sought for the safe and efficient synthesis of new nanoparticles, which have multifaceted applications in medicine. Unfortunately, the chemical synthesis of nanoparticles raises justified environmental concerns. A significant problem in their widespread use is also the toxicity of compounds that maintain nanoparticle stability, which significantly limits their clinical use. An opportunity for their more extensive application is the utilization of plants, fungi, and bacteria for nanoparticle biosynthesis. Extracts from natural sources can reduce metal ions in nanoparticles and stabilize them with non-toxic extract components.

Why Do Sulfone-Containing Polymer Photocatalysts Work So Well for Sacrificial Hydrogen Evolution from Water?

Many of the highest-performing polymer photocatalysts for sacrificial hydrogen evolution from water have contained dibenzo[b,d]thiophene sulfone units in their polymer backbones. However, the reasons behind the dominance of this building block are not well understood. We study films, dispersions, and solutions of a new set of solution-processable materials, where the sulfone content is systematically controlled, to understand how the sulfone unit affects the three key processes involved in photocatalytic hydrogen generation in this system: light absorption; transfer of the photogenerated hole to the hole scavenger triethylamine (TEA); and transfer of the photogenerated electron to the palladium metal co-catalyst that remains in the polymer from synthesis. Transient absorption spectroscopy and electrochemical measurements, combined with molecular dynamics and density functional theory simulations, show that the sulfone unit has two primary effects. On the picosecond timescale, it dictates the thermodynamics of hole transfer out of the polymer. The sulfone unit attracts water molecules such that the average permittivity experienced by the solvated polymer is increased. We show that TEA oxidation is only thermodynamically favorable above a certain permittivity threshold. On the microsecond timescale, we present experimental evidence that the sulfone unit acts as the electron transfer site out of the polymer, with the kinetics of electron extraction to palladium dictated by the ratio of photogenerated electrons to the number of sulfone units. For the highest-performing, sulfone-rich material, hydrogen evolution seems to be limited by the photogeneration rate of electrons rather than their extraction from the polymer.