Surface Chemistry Of Catalysts Research Articles

Influence of the catalyst surface chemistry on the electrochemical self-coupling of biomass-derived benzaldehyde into hydrobenzoin

Modifying the surface of Cu2S nanoparticles with OAm significantly influenced the selectivity of the BZH reduction reaction. Bare Cu2S favored the production of BA, while OAm-capped Cu2S promoted HDB formation.

Effect of catalyst surface chemistry and metal promotion on the liquid-phase ethanol condensation to higher alcohols

The production of higher alcohols (C4+) via ethanol liquid-phase condensation is studied in this work, screening catalysts with different acid/base properties, observing similarities but also relevant differences with respect to gas-phase reactions in the gas phase. The mechanistic analysis demonstrates the relevance of acidity, mainly to promote the dehydrogenation steps. In the same way, side reactions and hydrogenations have less relevance than in gas-phase, promoting the condensations and, subsequently, obtaining heavy compounds. The highest alcohol selectivity is reached with MgAl (2/1), with more than 79% of C4+ selectivity, but the activity of this material is conditioned by the low conversion obtained. The presence of water reduces the activity because of a competitive adsorption on the catalytic sites whereas the activity increases significantly when using bifunctional catalysts. The best results, obtained with 1% Cu/MgAl (2/1), allow rising the conversion up to more than 460% respect to the parent mixed oxide, with almost 44% of the alcohol mixture enriched in heavy compounds, mainly C6 and C8.

Shedding Synchrotron Light on Catalyst Strain Dynamics in Electrochemical Environment

In the case of heterogeneous catalysis (where the reactions occur onto the catalyst surface), the most promising approach in material design follows the Sabatier principle: the ability of the surface to bind adsorbates and the strength of the bonds define the reaction thermodynamics and kinetics. In this respect, the catalyst surface chemistry and structure (crystallographic orientation of the facets and/or strain) are used as levers to optimize its performance. However, it is largely accepted that the structure of PEMWE anode and PEMFC cathode catalysts does not remain unaltered over the long term operation due to harsh (electro)chemical conditions and it is of a high interest to understand the structural changes during the electrocatalysis. In this contribution we use X-ray diffraction techniques to qualitatively and quantitatively describe those changes and shed light on the strain evolution in nanostructured catalysts during operation in the electrochemical environment.Using the newly upgraded 4th generation EBS source at European Synchrotron Radiation Facility, we study Pt and Pd catalysts in liquid half cells at various potentials. In the Pd case we focus on the phase and structural dynamics during H insertion, allowing to unveil the electrochemically-driven Pd hydrides phase transition, which was until now mostly investigated in the gas phase. The fine XRD patterns measured operando provided the first detection of theoretically predicted supersaturated and undersaturated metastable states, involved in a core-shell mechanism of the phase transition (Figure 1) [1].In the case of Pt nanocatalyst, monitoring the structural features of the catalyst during cyclic voltammetry permits studying adsorption and oxidation processes. Deconvoluting both effects (adsorption and oxidation) is possible by following different parameters of the analyzed XRD patterns with high temporal resolution. Such experiments reveal important dynamic trends linked to the surface oxidation and degradation, directly impacting the output of accelerated stress tests (AST) [2]. Carefully determining the charge passed through the circuit during the CV also allows to establish a near-linear correlation between the expansion of the bulk lattice parameter of Pt nanoparticles and their oxide surface coverage. Since the latter is known to be a descriptor of catalysts activity toward numerous reactions (oxygen reduction and fuel oxidation), the measurement of the lattice parameter according to this simple diffraction approach allows experimental access to this descriptor during operando measurements in device-relevant sample environments [2]. This constitutes a main advantage compared to spectroscopic techniques and is foreseen to find a wide range of applications, as demonstrated by measuring the structural behavior of the state-of-the-art PtNiIr octahedra catalyst in operating PEMFC. In this case, the results allow correlating the degradation of the catalysts cycled to different lower potentials with the oxidation and strain dynamics. Based on this data, the operating conditions for this catalyst can be determined, further defining the application of this material.[1] Chattot, R. et al., J. Am. Chem. Soc. 143(41), 17068–17078 (2021).[2] Martens, I. et al., ACS Appl. Energy Mater. 2 (11), 7772-7780 (2019). Figure 1

Interface hydrophobic tunnel engineering: A general strategy to boost electrochemical conversion of N2 to NH3

Electrocatalytic nitrogen reduction reaction (NRR), which can produce ammonia from N2 and H2O under ambient conditions, has emerged as a promising sustainable alternative to the Haber-Bosch (H-B) process. However, their unsatisfied conversion efficiency and selectivity severely restrict the real utilization of NRR, owing to the stubborn triple bond in the N2 molecule and the competitive hydrogen evolution reaction (HER). Here, inspired from the local microenvironment of the nitrogenase, we report for the first time a facile and general strategy to boost the NRR selectivity and activity through the self-assembled monolayer (SAM) of hexanethiol (HEX) on a series of metal electrocatalysts (Cu, Au, Pt, Pd and Ni). Molecular dynamics (MD) simulations suggest that the HEX SAM provides a hydrophobic microenvironment to impede the diffusion and adsorption of water molecules and promote that of N2 molecules, thus inhibiting HER and simultaneously improving the NRR performance. Notably, among all the prepared samples, the highest Faradic efficiency (FE) of 50.5% is achieved on Cu-HEX with NH3 formation rate (R) of 1.2 μg h−1 cm−2. Remarkably, for the HER-favored Pt catalyst, the highest R of 26.4 μg h−1 cm−2 is also achieved on Pt-HEX with FE of 1.8% under 1 cm2 of electrode area. The present strategy not only represents a general diffusion-controlled method to engineer high-performance NRR electrocatalysts, but also provides a new insight into the effect of surface chemistry of catalysts on the NRR process and kinetics.

The best of both worlds in material synthesis to understand metal-support interactions

The best of both worlds in material synthesis to understand metal-support interactions

Dynamic Surface Chemistry of Catalysts in Oxygen Evolution Reaction

Dynamic Surface Chemistry of Catalysts Dynamic surface chemistry controls the oxygen evolution reaction (OER) under a given set of electrocatalytic servicing conditions. In article number 2100011, Zongkui Kou, Xin Li, Xiaorui Gao, John Wang, and co-workers review two competing processes, reversible and irreversible reconstruction, where the balance is affected by both the pre-catalyst internal and externally applied field factors. To develop efficient and durable electrocatalysts for OER, real-time in-situ and operando techniques, with multiscale computational studies are discussed.

Recent Advances in Carbon Dioxide Conversion: A Circular Bioeconomy Perspective

Managing the concentration of atmospheric CO2 requires a multifaceted engineering strategy, which remains a highly challenging task. Reducing atmospheric CO2 (CO2R) by converting it to value-added chemicals in a carbon neutral footprint manner must be the ultimate goal. The latest progress in CO2R through either abiotic (artificial catalysts) or biotic (natural enzymes) processes is reviewed herein. Abiotic CO2R can be conducted in the aqueous phase that usually leads to the formation of a mixture of CO, formic acid, and hydrogen. By contrast, a wide spectrum of hydrocarbon species is often observed by abiotic CO2R in the gaseous phase. On the other hand, biotic CO2R is often conducted in the aqueous phase and a wide spectrum of value-added chemicals are obtained. Key to the success of the abiotic process is understanding the surface chemistry of catalysts, which significantly governs the reactivity and selectivity of CO2R. However, in biotic CO2R, operation conditions and reactor design are crucial to reaching a neutral carbon footprint. Future research needs to look toward neutral or even negative carbon footprint CO2R processes. Having a deep insight into the scientific and technological aspect of both abiotic and biotic CO2R would advance in designing efficient catalysts and microalgae farming systems. Integrating the abiotic and biotic CO2R such as microbial fuel cells further diversifies the spectrum of CO2R.

Dynamic Surface Chemistry of Catalysts in Oxygen Evolution Reaction

Electrocatalytic oxygen evolution reaction (OER) is a crucial anode reaction where electrocatalysts are the key elements and their dynamic surface chemistry runs throughout the entire process. Herein, we examine the latest advances and challenges in understanding of the dynamic surface chemistry of OER electrocatalysts. There are electrochemical origin and driving force for the dynamic surface nature, where several processes can take place either concurrently or sequentially, including reconstruction (i.e., phase formation/transformation, morphological change, and compositional change), vacancy generation and filling/refilling, and the intermediate adsorption–desorption process on catalytic surface. These dynamic surface processes of OER catalysts are impacted by not only the reaction and service conditions, including the (local) pH and its gradient distribution, applied potential, types and concentration of exotic ions and external fields on top of the nature of catalysts/precatalysts, but also their interactions. Due to the local, time‐dependent and instant nature, there are considerable challenges in tracing, modelling and understanding of the complete dynamic surface chemistry of catalysts in OER, by means of ex situ, in situ and operando experimental investigations. Therefore, computational studies and dynamic simulations help provide key insights in future pursuits, where there is critical need for a multiscale computational modelling approach encompassing all these aspects.

Underappreciated Role of Low-Energy Facets in Nitrogen Electroreduction

Electrocatalytic nitrogen reduction reaction (NRR) is a promising route to replace the energy-intensive Haber–Bosch process. However, weak nitrogen-surface interaction impedes the reaction efficiency and demands better understanding of the catalyst surface chemistry. Here, we expand the design rules for NRR to include the low-energy smooth surfaces, in contrast to conventional wisdom favoring irregular or high-index facets, grain boundaries, and edge sites. Our Ni3S4 catalyst with low-energy facets achieves a 6.8 ± 3.3% Faradaic efficiency (FE) for NRR, compared to 1.9 ± 3.6% for a control of the same crystal structure and composition but with a more disordered surface. First-principles calculations reveal that the synthetic conditions allow choosing whether Ni-rich or S-rich surfaces would be more stable, which affects the coordination of the active Ni site and its reactivity. In addition, the combination of Lewis acid and Lewis base sites allows separating the adsorption of different reactants, resulting in a suppression of the competing hydrogen evolution reaction.

Role of impurity components and pollutant removal processes in catalytic oxidation of o-xylene from simulated coal-fired flue gas

Volatile organic compounds (VOCs) emitted from coal-fired flue gas of thermal power plants have reached unprecedented levels due to lack of understanding of reaction mechanisms under industrial settings. Herein, inhibition mechanisms for catalytic oxidation of o-xylene in simulated coal-fired flue gas are elucidated with in-situ and ex-situ spectroscopic techniques considering the presence of impurity components (NO, NH3, SO2, H2O). MnCe oxide catalysts prepared at Mn: Ce mass ratios of 6:4 are demonstrated to promote 87% o-xylene oxidation at 250 °C under gas hourly space velocities of 60,000 h−1. Reaction intermediates on the catalyst surface are revealed to be o-benzoquinones, benzoates, and formate and they were stably formed under O2/N2 atmospheres. When either NO or NH3 was introduced into the simulated flue gas, the formed species shifted toward formate in minutes, which indicated that changes in catalyst surface chemistry are directly related to impurity components. Presence of NH3 in the simulated flue gas inhibited o-xylene oxidation by reducing Mn and lowering Brønsted acidity of the catalyst. Impurity components associated with pollutant removal processes (Hg0 oxidation and selective catalytic reduction of NO) lowered o-xylene removal efficiency. Presence of o-xylene in the flue gas had little effect on the efficiency of pollutant removal processes. Layered catalytic beds located downstream from Hg0/NO pollutant removal processes are proposed to lower VOC emissions from coal-fired flue gases of thermal power plants in industrial settings.

Temperature-enabled reversible “On/Off” switch-like hazardous herbicide picloram voltammetric sensor in agricultural and environmental samples based on thermo-responsive PVCL-tethered MWCNT@Au catalyst

Picloram (PCR), a vastly utilized chlorinated herbicide, is very stable in water and soil with severe ecological and health impacts. It is necessary to establish a fast and highly sensitive technique for accurately detecting trace level PCR in agricultural and environmental samples. We employed a temperature-responsive poly(N-vinylcaprolactam)-tethered multiwalled carbon nanotubes (MWCNT-PVCL) decorated gold nanoparticles (Au@MWCNT-PVCL) catalyst on the electrochemical sensor for the sensitive “On/Off” switch-like detection of PCR. The effect of temperature-sensitive catalyst surface chemistry on electrocatalytic activity was scrutinized. Results showed that the hydrophilic surface of PVCL at 25 °C (<lower critical solution temperature (LCST)) extended to bury the electroactive sites of Au nanoparticles and MWCNT, and the PCR unable to pass over the PVCL to achieve electron exchange process, signifying the “Off” state. Surface wettability of the prepared Au@MWCNT-PVCL then spontaneously switched its hydrophilic to hydrophobic surface one at 40 °C (>LCST) that immensely upgraded PCR oxidation on the catalyst in the electrochemical reaction, signifying the “On” state. The detection of the Au@MWCNT-PVCL modified electrode ranged from 0.02–183 μM with a low detection limit (LOD) of 1.5 nM at 40 °C toward PCR. The proposed sensor was successfully used to detect PCR in real agricultural and environmental samples.

Visualizing the importance of oxide-metal phase transitions in the production of synthesis gas over Ni catalysts

Abstract Synthesis gas, composed of H2 and CO, is an important fuel which serves as feedstock for industrially relevant processes, such as methanol or ammonia synthesis. The efficiency of these reactions depends on the H2: CO ratio, which can be controlled by a careful choice of reactants and catalyst surface chemistry. Here, using a combination of environmental scanning electron microscopy (ESEM) and online mass spectrometry, direct visualization of the surface chemistry of a Ni catalyst during the production of synthesis gas was achieved for the first time. The insertion of a homebuilt quartz tube reactor in the modified ESEM chamber was key to success of the setup. The nature of chemical dynamics was revealed in the form of reversible oxide-metal phase transitions and surface transformations which occurred on the performing catalyst. The oxide-metal phase transitions were found to control the production of synthesis gas in the temperature regime between 700 and 900 °C in an atmosphere relevant for dry reforming of methane (DRM, CO2: CH4 =0.75). This was confirmed using high resolution transmission electron microscopy imaging, electron energy loss spectroscopy, thermal analysis, and C18O2 labelled experiments. Our dedicated operando approach of simultaneously studying the surface processes of a catalyst and its activity allowed to uncover how phase transitions can steer catalytic reactions.

The role of surface N[sbnd]H groups on the selective hydrogenation of cinnamaldehyde over Co/BN catalysts

The surface chemistry of catalyst plays a vital role in the catalytic process. And the effects of surface groups of porous boron nitride (p-BN) on the hydrogenation reaction have not been studied in detailed. In this work, two main surface species of Co/p-BN catalyst were tuned thermally and their roles on the hydrogenation reaction were discriminated by α, β-unsaturated aldehyde hydrogenation reaction. The surface BO content decreased at higher reduction temperature and the cobalt phase changed from CoO to the mixture of CoO and Co0. The Co/p-BN-500 exhibited the highest selectivity to CO hydrogenation. And its turnover frequency (TOF) of 13.2 h−1 is close to the optimal value of reported cobalt catalysts. When the reaction proceeds, hydrogenation rate of CO increases but that of CC decreases gradually, thus a surface groups variation was expected at the initial period. Further in-situ FTIR spectra showed the band intensity of edge NH increases as the adsorption proceeds at 50°С but it decreases as the temperature rise to 200°С, in combined with the shift of CO adsorption peak, a intermolecular hydrogen bond between edge NH and the terminal CO group was suggested, which account for the better selectivity to CO than CC.

Understanding Catalyst Surfaces during Catalysis through Near Ambient Pressure X-ray Photoelectron Spectroscopy.

Heterogeneous catalysis occurs on the surface of a catalyst particle in a gas or liquid environment of reactants. The surface of the catalyst particle acts as an active chemical agent directly participating in a chemical reaction performed at a solid-gas or solid-liquid interface. Thus, authentic surface chemistry and the structure of a catalyst particle during catalysis are key descriptors for understanding catalytic performance of this catalyst. However, identification of the authentic surface of a catalyst particle during catalysis is not a simple task. We are far from knowing the fact. Photoelectron spectroscopy is one of the main techniques for characterizing surface of a catalyst since it's a surface sensitive technique. When used to track the surface of a catalyst particle at relatively high temperature in gas phase in the torr pressure range, it is called near ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) or AP-XPS for simplicity. In the last several years, AP-XPS has been used to observe surface chemistry of catalysts of single crystals and nanoparticles of metal, metal oxide, and carbide. In this review, instrumentation of the near ambient pressure X-ray photoelectron spectrometers and observation of catalyst surfaces in gases phase under reaction conditions and during catalysis with AP-XPS are discussed with the following objectives: (1) to present how the surface of a catalyst particle can be characterized in gas phase, (2) to interpret how surface chemistries observed during catalysis are correlated with measured catalytic performances, (3) to demonstrate how the uncovered correlations between surface structures and catalytic performances help to understand catalytic mechanisms at a molecular level, and (4) to discuss challenges and prospects of using AP-XPS to explore the authentic surface of a catalyst under a condition near to an industrial catalytic condition. This review focuses on the application of AP-XPS to studies of catalysis and how the insights gained from AP-XPS studies can be used to achieve fundamental understanding of the catalytic mechanism at a molecular level.

A Bimetallic Electrocatalyst Platform for Understanding the Roles of Surface Chemistry and Functionalization on Nitrogen Reduction to Ammonia

The Haber-Bosch industrial process for ammonia production is the cornerstone of modern commercial-fertilizer-based agriculture. Haber-Bosch ammonia fueled the global population growth of the 20th century, and approximately half of the nitrogen in human bodies today originates from ammonia-based fertilizer produced by the Haber-Bosch process. However, the Haber-Bosch process operates at high temperature and high pressure to achieve high conversion efficiencies, and the hydrogen input comes from steam reforming of coal or natural gas. In addition to the energy costs, the large production of carbon dioxide as a greenhouse gas and the large required economies of scale motivate research efforts to explore other possible options for ammonia production. One potential option is low temperature electrochemical synthesis of ammonia from nitrogen and water. An electrochemical process that directly synthesizes ammonia molecules from nitrogen gas and the hydrogen atoms of water molecules would eliminate the need for fossil-fuel-based hydrogen as a reactant and decrease CO2 emissions. Further, an electrochemical system based on already-developed technology in the fuel cell and electrolysis arenas would enable a modular, scalable, and energy efficient process that could be connected to renewables (i.e., wind or solar) as the energy input. While electrochemical ammonia synthesis is an enticing option in theory, in practice the process is severely limited by the lack of available catalysts that can produce ammonia at high Faradaic efficiencies. All heterogeneous catalyst surfaces that are active for the reduction of di-nitrogen to ammonia in the presence of water are also highly active for the reduction of water molecules to hydrogen gas. Both reactions occur within a similar potential range, and thus electrochemical systems will inherently battle against this reaction selectivity issue. Today, all reported heterogeneous catalysts remain limited to low efficiencies of less than 1% for ammonia production at low temperature because the majority of the applied electrical potential goes towards water splitting and the evolution of hydrogen. In our research, we are interested in understanding how catalyst surface chemistry and ligand functionalization can be used to direct and control reaction selectivity of the electrocatalyst. We synthesize non-precious metal-based catalysts comprised of iron and nickel, which, as a bimetallic material, are theoretically-predicted to potentially result in optimal surfaces for nitrogen reduction. However, these mixed oxide/hydroxide surfaces are also expected to still be dominated by hydrogen adsorption and evolution. Thus, to further address reaction selectivity and create a catalyst surface that is more selective for ammonia synthesis, we also design our catalysts such that the local surface environment of the catalyst is controlled through ligand functionalization. In this talk, our ongoing work to design, synthesize and characterize iron-nickel hydroxide bimetallic catalysts for efficient electrochemical ammonia synthesis will be discussed.

Controlling the surface chemistry towards unsaturated carbon-carbon bonds over non-oxide transition metal ceramics: Trends in adsorption and distortion energies and adsorbate “activation”

Controlling the surface chemistry of catalysts towards unsaturated carbon-carbon bonds is vital to achieving many contemporary chemical transformations. Transition metal (TM) ceramics are promising materials that exhibit lower and tunable surface reactivity towards C=C bonds. Herein, we have employed an analysis of the adsorption of benzene over a large suite of TM ceramic and pure metal surfaces to benchmark a large selection of materials to isolate trends. Results showed a wide range of surface reactivity as a function of the constituent elements, surface composition, TM-to-p-element ratio, surface ensemble size, electronic structure, etc. The 1st row TM ceramics exhibited lower surface reactivity and more stable surface composition than the 2nd/3rd TM ceramics suggesting that orbital-size match could be a simple marker for predicting general surface chemistry and surface composition stability in TM solid compounds. The TM-to-p-element ratio also generally dictated metal-like or markedly-modified reactivity of the constituent elements at the ceramic surface. Electronic analysis further quantified the correlation between the density and type of electronic states near the Fermi level and the reactivity of surface-lattice elements. Structural and energetic analysis of the adsorbed benzene indicated the activation of the adsorbate could be better quantified beyond simple adsorption energy.

Multi‐Light‐Responsive Quantum Dot Sensitized Hybrid Micromotors with Dual‐Mode Propulsion

AbstractCdS quantum dots/C60 tubular micromotors with chemical/multi‐light‐controlled propulsion and “on‐the‐fly” acceleration capabilities are described. In situ growth of CdS quantum dots on the outer fullerene layer imparts this layer with light‐responsive properties in connection to inner Pt, Pd or MnO2 layers. This is the first time that visible light is used to drive bubble‐propelled tubular micromotors. The micromotors exhibit a broad absorption range from 320 to 670 nm and can be wirelessly controlled by modulating light intensity and peroxide concentration. The built‐in accelerating optical system allows for the control of the velocity over the entire UV/Vis light spectra by modulating the catalyst surface chemistry. The light‐responsive properties have been also exploited to accelerate the chemical dealloying and propulsion of micromotors containing a Cu/Pd layer. Such dual operated hybrid micromotors hold considerable promise for designing smart micromachines for on‐demand operations, motion‐based sensing, and enhanced cargo transportation.

Recent Improvements in the Production of Solar Fuels: From CO2 Reduction to Water Splitting and Artificial Photosynthesis

Abstract This account deals with recent trends and challenges regarding photo(electro)chemical solar fuels produced by CO2 reduction and water splitting. The CO2 reduction process is limited by product selectivity, catalyst stability, and its complex reaction mechanism. A variety of catalysts—including thermocatalysts, photocatalysts, electrocatalysts, and combinations of photo- and electrocatalysts—have been employed to facilitate selective and durable CO2 reduction. In addition, the roles of the supporting electrolyte, pH, reaction temperature, chemical environment, and catalyst surface chemistry in efficient CO2 reduction have been thoroughly studied in recent years. Effective use of solar light is a significant part of realizing efficient solar-to-hydrogen conversion during the water splitting process, and so the response of photo(electro)systems to visible light is key. To this end, several strategies have been studied in detail, including band engineering of photocatalysts, photocatalytic systems that mimic natural photosynthesis, and the development of photoanodes and their combination with photovoltaic systems. Here, we summarize recent developments surrounding the CO2-reduction and water-splitting reactions and progress towards achieving artificial photosynthesis.

Multi-Light-Responsive Quantum Dot Sensitized Hybrid Micromotors with Dual-Mode Propulsion.

CdS quantum dots/C60 tubular micromotors with chemical/multi-light-controlled propulsion and "on-the-fly" acceleration capabilities are described. In situ growth of CdS quantum dots on the outer fullerene layer imparts this layer with light-responsive properties in connection to inner Pt, Pd or MnO2 layers. This is the first time that visible light is used to drive bubble-propelled tubular micromotors. The micromotors exhibit a broad absorption range from 320 to 670 nm and can be wirelessly controlled by modulating light intensity and peroxide concentration. The built-in accelerating optical system allows for the control of the velocity over the entire UV/Vis light spectra by modulating the catalyst surface chemistry. The light-responsive properties have been also exploited to accelerate the chemical dealloying and propulsion of micromotors containing a Cu/Pd layer. Such dual operated hybrid micromotors hold considerable promise for designing smart micromachines for on-demand operations, motion-based sensing, and enhanced cargo transportation.

NO oxidation in dry and humid conditions using hyper-cross-linked polymers: Impact of surface chemistry on catalytic conversion efficiency

Microporous and hydrophobic polymers were synthesized and tested as NO oxidation catalysts to overcome water co-adsorption in combustion flue gas streams. The self-cross-linked 4,4′-bis(chloromethyl)-1,1′-biphenyl polymer (PBCMBP), with micropore volume of 0.38 cm3/g and surface area of 1430 m2/g, provided 62% NO oxidation efficiency at 25 °C in dry conditions but its performance dropped to 50% in the presence of 1.6 vol% moisture (wet conditions). To decrease performance loss, PBCMBP was modified with benzene (PBCMBP-BZ) to remove pendant chloromethyl groups, improving resistance to surface reactions with NO2 that add hydrophilicity. In wet conditions, PBCMBP-BZ has 59% NO oxidation efficiency, an 18% increase compared to PBCMBP at 25 °C. PBCMBP was also functionalized with dimethylamine (PBCMBP-DMA) to increase surface basicity, increasing NO oxidation by 11% in dry conditions, but decreasing NO oxidation in wet conditions by 30% due to increased proclivity to react with NO2. The combined impact of temperature and humidity was measured up to 100 °C, showing that moisture’s impact decreases with increasing temperature and that PBCMBP-DMA outperforms other catalysts at higher temperatures. Findings suggest that catalyst surface chemistry can be manipulated to further improve NO oxidation performance, especially in the presence of moisture.