Hybrid Catalyst Research Articles

Silver Single Atoms Combined with Clusters on Carbon Nanotubes Mediates Exclusive Electrochemical CO2‐to‐CO Conversion

AbstractThe electrochemical reduction of CO2 (eCO2RR) that exclusively produces one product at industrial current density is crucial for the substantial storage of renewable energy. Modulating the electronic structure of atomically dispersed catalysts can effectively regulate the adsorption of rate‐determining‐step intermediates to achieve the desired products. Here, the study constructs a hybrid catalyst consisting of single Ag atoms and Ag atomic clusters supported on nitrogen‐doped multi‐walled carbon nanotubes that can effectively regulate the important intermediate structure of *COOH. The X‐ray photoelectron and X‐ray absorption near‐edge spectroscopies demonstrate that turning Ag single atoms into Ag clusters can weaken the electron transfer between Ag–N and present a relatively rich electron state. Thus, the rate‐determining step of *COOH massive formation is significantly accelerated, as proven by in situ synchrotron infrared spectroscopy and density functional theory calculations. Using this strategy, a CO Faradaic efficiency outperforming 99% from −0.3 to −0.8 V (vs reversible hydrogen electrode) with current densities above 200 mA cm−2 and a half‐cell energetic efficiency of 86% is achieved. This work highlights a promising approach to advancing synergistic catalysts for achieving more controllable and efficient eCO2RR.

Selective Synthesis of Formyl‐2‐Furancarboxylic Acid via Enhanced Adsorption of 5‐Hydroxymethylfurfural on Composite Catalysts

5‐Hydroxymethylfurfural (HMF) is a widely used biomass platform chemical that plays a crucial role in bridging biomass and fossil resources. Electrocatalytic oxidation of HMF provides an efficient way to obtain high‐value‐added biomass‐derived chemicals, among which the intermediate product 5‐formyl‐2‐furan carboxylic acid (FFCA) has attracted considerable attention. However, the weak adsorption ability of monometallic nickel oxide (NiOx) to HMF in neutral electrolyte restricts its further development, resulting in low HMF conversion and FFCA yield. In this study, we successfully constructed a novel nickel oxide‐platinum oxide hybrid catalyst supported on carbon felt (NiOx‐PtOx/CF), which exhibits an optimized adsorption ability of HMF, leading to the outstanding FFCA yield up to 77% in the neutral media. The high activity of the NiOx‐PtOx/CF catalyst can be attributed to the redistribution of the electrons and the optimization of the electronic structure on the Ni active site due to the introduction of PtOx on NiOx nanosheets. This study offers valuable insights for the design of efficient multicomponent electrocatalysts for electrocatalytic biomass refinery systems.

Carbon-supported hydroxyapatite hybrid catalysts for butan-1-ol conversion: Effect of the nature of carbon support on process selectivity

Hybrid systems of hydroxyapatite supported on carbonaceous materials of different nature (activated charcoals, acetylene black, carbon black, graphite flake, synthesized microporous and mesoporous carbons) are investigated as catalysts for vapor-phase Guerbet condensation of butan-1-ol. The structure, morphology, and acid–base characteristics of hydroxyapatite, carbon supports, and the hybrid systems have been characterized by XRD, SEM-EDX, low-temperature (77 K) nitrogen ad(de)sorption, NMR, XPS, EPR, Raman spectroscopy, and TPD-NH3/CO2 techniques. The butan-1-ol conversion and selectivity towards the reaction products are found to be highly dependent on carbonaceous supports of the hybrid catalysts. The important role of acid–base capacity ratio is highlighted to achieve high selectivity in vapor-phase Guerbet condensation of butan-1-ol to 2-ethylhexan-1-ol. In particular, the surface’s strong basic sites are preferable for elongating the carbon chain. The high selectivity towards 2-ethylhexan-1-ol of about 75% is achieved over HAP/graphite flake and up to 57% over HAP/activated coconut charcoal. Compared to the bulk hydroxyapatite, the enhanced performance of the hybrid catalysts (initial activity and target product yield) is associated with the redistribution of active sites over carbon supports by strength and location.

Copper/Polyaniline Interfaces Confined CO2 Electroreduction for Selective Hydrocarbon Production.

Polyaniline (PANI) provides an attractive organic platform for CO2 electrochemical reduction due to the ability to adsorb CO2 molecules and in providing means to interact with metal nanostructures. In this work, a novel PANI supported copper catalyst has been developed by coupling the interfacial polymerization of PANI and Cu. The hybrid catalyst demonstrates excellent activity towards production of hydrocarbon products including CH4 and C2H4, compared with the use of bare Cu. A Faradaic efficiency of 71.8 % and a current density of 16.9 mA/cm2 were achieved at -0.86 V vs. RHE, in contrast to only 22.2 % and 1.0 mA/cm2 from the counterpart Cu catalysts. The remarkably enhanced catalytic performance of the hybrid PANI/Cu catalyst can be attributed to the synergistic interaction between the PANI underlayer and copper. The PANI favours the adsorption and binding of CO2 molecules via its nitrogen sites to form *CO intermediates, while the Cu/PANI interfaces confine the diffusion or desorption of the *CO intermediates favouring their further hydrogenation or carbon-carbon coupling to form hydrocarbon products. This work provides insights into the formation of hydrocarbon products on PANI-modified Cu catalysts, which may guide the development of conducting polymer-metal catalysts for CO2 electroreduction.

Design and synthesis of Co@NiSe catalyst for efficient 2e− ORR in neutral electrolyte: Effect of electronic structure engineering

Two-electron oxygen reduction reaction (2e− ORR) generating hydrogen peroxide (H2O2) in neutral electrolytes is currently encountering significant scientific challenges. Here, we adopted a direct electron transfer and defect engineering approach for synthesizing a Co-doped NiSe hybrid catalyst to boost the efficiency of this reaction system. The Co@NiSe catalyst with long-term stability over 160 h showed a 53.1 % increase in H2O2 selectivity comparing with the pristine NiSe material in neutral electrolyte, indicating the effective modulation of the electronic structure of NiSe via Co doping. Impressively, the 2e− ORR catalytic activity of the catalysts exhibited a positive linear dependence on the content of Ni2+ species. The present research proved the possibility for improving the activity of transition metal-based catalysts in neutral electrolytes via hetero-atom doping, which had built basic structure-function relations for designing highly efficient 2e− ORR system.

Hybrid catalyst‐assisted synthesis of multifunctional carbon derived from Camellia shell for high‐performance sodium‐ion batteries and sodium‐ion hybrid capacitors

AbstractBiomass‐derived carbon as energy storage materials have gradually attracted widespread attention due to their low cost, sustainability, and inherent structural advantages. Herein, hard carbon (H‐1200) and porous carbon (PC‐800) for sodium‐ion batteries (SIBs), sodium‐ion capacitors (SICs) half cells and sodium‐ion hybrid capacitors (SIHCs) have been synthesized from the same biomass precursor of Camellia shells through different treatments. H‐1200 synthesized by directly high‐temperature carbonization possesses a rational graphitic layer structure and plentiful heteroatoms. When applied as anode for SIBs, it exhibits a reversible capacity of 365.5 mAh g–1 at 25 mA g–1 and capacity retention 89.0% after 400 cycles at 200 mA g–1. Additionally, PC‐800 prepared by catalytic carbonization of K2C2O4/CaC2O4 hybrid catalyst has a sophisticated porous structure and a high surface area of 2186.9 m2 g–1. When employed as a cathode for SICs, it delivers a maximum capacity 104.2 mAh g–1 at 100 mA g–1 and 35.0 mAh g–1 at 5 A g–1. Furthermore, the all carbon assembled SIHC (H‐1200||PC‐800) using H‐1200 as anode and PC‐800 as cathode, features a broad output voltage range (0.01 ~ 4.1 V), high energy density of 161.5 Wh kg–1, power density of 12896.1 W kg–1, and superior capacity retention of 90.32% after 10000 cycles at 10 A g–1. This research result provide a new horizon for constructing low‐cost and large‐scale production of biomass derived carbon for energy storage materials.

PtCo-ZIF-derived hybrid electrocatalysts comprising an ordered PtCo alloy and a single-atoms-decorated carbon shell for the oxygen reduction reaction

Recent research on hybrid catalysts showed that Pt-based alloy particles surrounded by a single-atoms-decorated carbon shell exhibit promising oxygen reduction reaction catalytic activity and durability owing to the synergistic effect. However, the structural complexity of these hybrid catalysts renders their synthesis challenging. This study synthesized a mixed-metal zeolitic imidazolate framework (ZIF) containing Pt and Co ions coordinated with a benzimidazole ligand, which was used as a scaffold to fabricate hybrid catalysts comprising uniform PtCo intermetallic alloy particles coated with a thin N-doped carbon shell containing numerous Pt and Co single atoms via one-step annealing. Without post-treatment, the mass and specific activities of the synthesized catalyst were significantly higher than those of the commercial Pt/C catalyst. Additionally, the synthesized catalyst exhibited ultra-long-term durability, meeting the 2025 target of the U.S. Department of Energy, even after 300 000 cycles of an accelerated durability test.

S-scheme charge transfer and photoinduced self-heating effect synergistically enhance the solar-driven CO2 reduction over Cs3Bi2Br9/Bi2S3 hybrid

Photothermocatalytic CO2 reduction, which harnesses the solar power to not only supply heat input but also generate charge carriers, represents an attractive and sustainable approach for solar-to-fuel conversion. Herein, an innovative Cs3Bi2Br9/Bi2S3 (CBB/Bi2S3) hybrid catalyst was elaborately designed by an electrostatic-driven self-assembling approach, which can achieve the effect of “kill two birds with one stone”. On the one hand, Bi2S3 functions as a photothermal material owing to its photoinduced self-heating effect, which elevates the temperature of the catalyst for accelerating the catalytic reaction. On the other hand, Bi2S3 synchronously boosts charge separation by forming an S-scheme heterojunction with CBB, as revealed by first-principle simulation and a series of experimental techniques. Remarkably, the developed CBB/Bi2S3 hybrid affords an impressive CO production rate (RCO = 153.82 μmol g−1h−1) without any extra heat input. The present study can provide some enlightening guidance for developing high-performance photothermal catalysts for efficient CO2 conversion.

A dual-purpose photocatalytic reaction for hydrogen evolution and simultaneous organic pollutant degradation of V2O5/Ppy based composite photocatalyst

The present work reports for the facile synthesis of novel vanadium oxide/polypyrrole (V2O5/Ppy) nanohybrids using various loadings of the V2O5. This novel hybrid photocatalyst was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman, UV–Visible absorption spectra (UV–Vis), photoluminescence spectra (PLS) and N2 adsorption-desorption analysis. XRD and TEM results suggest that V2O5 with individual spherical shaped nanoparticles of around 20–25 nm, which is uniformly wrapped on the surface of the Ppy sheets. A significant reduction in the bad gap energy (3.06–2.13 eV) and prevent the electron-hole recombination process was examined by UV and PL studies. The photocatalytic degradation efficiency was carried out for Reactive Black 31 (RB 31) and 4-chlorophenol (4-CP) dyes under visible light. The results illustrate that the optimal hybrid catalyst could reach 99 % of removal efficiency towards RB31 with visible light irradiation for 60 min. Moreover, the catalyst show high TOC efficiency (88%) high apparent constant (0.9189 min−1), and good stability with multiple cycle experiments. The improved photocatalytic mechanism was also discussed in detail. In comparison to V2O5 (425 μmol−1h−1 of H2) and PPy (151 μmol−1h−1 of H2), the optimised composite, 15 wt% V2O5 incorporated PPy showed a remarkable production rate under visible light (2255 μmol−1h−1 of H2).

Efficient Visible Light Photocatalytic Hydrogen Evolution by Boosting the Interfacial Electron Transfer in Mesoporous Mott-Schottky Heterojunctions of Co2P-Modified CdIn2S4 Nanocrystals.

Photocatalytic water splitting for hydrogen generation is an appealing means of sustainable solar energy storage. In the past few years, mesoporous semiconductors have been at the forefront of investigations in low-cost chemical fuel production and energy conversion technologies. Mesoporosity combined with the tunable electronic properties of semiconducting nanocrystals offers the desired large accessible surface and electronic connectivity throughout the framework, thus enhancing photocatalytic activity. In this work, we present the construction of rationally designed 3D mesoporous networks of Co2P-modified CdIn2S4 nanoscale crystals (ca. 5-6 nm in size) through an effective soft-templating synthetic route and demonstrate their impressive performance for visible-light-irradiated catalytic hydrogen production. Spectroscopic characterizations combined with electrochemical studies unravel the multipathway electron transfer dynamics across the interface of Co2P/CdIn2S4 Mott-Schottky nanoheterojunctions and shed light on their impact on the photocatalytic hydrogen evolution chemistry. The strong Mott-Schottky interaction occurring at the heterointerface can regulate the charge transport toward greatly improved hydrogen evolution performance. The hybrid catalyst with 10 wt % Co2P content unveils a H2 evolution rate of 20.9 mmol gcat -1 h-1 under visible light irradiation with an apparent quantum efficiency (AQE) up to 56.1% at 420 nm, which is among the highest reported activities. The understanding of interfacial charge-transfer mechanism could provide valuable insights into the rational development of highly efficient catalysts for clean energy applications.

Post-treatment induced anisotropic growth of MOF-derived surface modified heterogeneous catalyst for efficient oxygen evolution reaction

The advancement of electrocatalysts exhibiting outstanding performance in the oxygen evolution reaction (OER), crucial for hydrogen production, holds immense significance in addressing energy shortages and mitigating environmental pollution. In this study, a novel approach to synthesizing Co-MOF (Metal-Organic Framework) directly immobilized onto a Ni foam substrate through hydrothermal synthesis is presented. In contrast to conventional methods employing powder-based synthesis with binders, our direct attachment method offers a unique and efficient means of creating robust Co-MOF at Ni foam (Co-MOF@NF) hybrid catalysts. Subsequently, a chemical reduction approach utilizing sodium borohydride was employed to introduce surface modification into the Co-MOF structure. The resulting material, sodium borohydride treated Co-MOF@NF (Red. 1 h Co-MOF@NF), exhibited a remarkable enhancement in OER activity compared to the pristine Co-MOF@NF sample. Notably, Red.1 h Co-MOF@NF demonstrated a substantially reduced overpotential of 235 mV to achieve a current density of 10 mA cm⁻2, in contrast to the 300 mV overpotential required by the pristine Co-MOF@NF under the same conditions. Furthermore, the Red.1 h Co-MOF@NF catalyst displayed exceptional stability, sustaining a current density of 50 mA cm⁻2 for over 48 h, highlighting its promising potential for practical applications. The synergistic effects of direct hydrothermal attachment, surface modification, and improved OER performance make this study a significant contribution to the advancement of efficient and stable electrocatalysts for energy conversion applications.

Enhanced photocatalytic degradation of rhodamine B dye and antibacterial activity of diatomite-supported TiO2/ZnS hybrid catalyst via additional calcination

Enhanced photocatalytic degradation of rhodamine B dye and antibacterial activity of diatomite-supported TiO2/ZnS hybrid catalyst via additional calcination

Revealing the two distinctive roles of HY zeolite in enhancing the activity and durability of manganese oxide-zeolite hybrid catalysts for low-temperature NH3-SCR

Recently, metal oxide-zeolite hybrid systems have shown promise in enhancing catalytic performance in low-temperature selective catalytic reduction (SCR), but not much is known as to mechanistic details. The purpose of this study is to examine fluctuations in low-temperature activity contingent upon the presence or absence of zeolite and to elucidate a dual functional mechanism of mixed zeolite in improving the catalytic performance of MnOx, which is closely related to inter-particle diffusion of nitrite and nitrate species from MnOx to zeolite. Firstly, strong Brønsted acid sites on zeolite demonstrate a significantly faster reduction of diffused nitrite species compared to Brønsted/Lewis acid sites on MnOx. More importantly, we discovered that zeolite prevents ammonium nitrate deposition by absorbing and decomposing diffused nitrate species from MnOx. Such distinct interaction between zeolite and both nitrite and nitrate species clarified here will be of great promise in designing future hybrid catalytic materials for low-temperature NH3-SCR reactions.

One-pot synthesis of NiCo-phyllosilicate supported on zeolite for enhanced degradation of antibiotic contaminants

The overuse of antibiotics currently results in the presence of various antibiotics being detected in water bodies, which poses potential risks to human health and the environment. Therefore, it is highly significant to remove antibiotics from water. In this study, we developed novel rod-like NiCo-phyllosilicate hybrid catalysts on calcined natural zeolite (NiCo@C-zeolite) via a facile one-pot process. The presence of the zeolite served as both a silicon source and a support, maintaining a high specific surface area of the NiCo@C-zeolite. Remarkably, NiCo@C-zeolite exhibited outstanding catalytic performance in antibiotic degradation under PMS activation. Within just 5 min, the degradation rate of metronidazole (MNZ) reached 96.14%, ultimately achieving a final degradation rate of 99.28%. Furthermore, we investigated the influence of catalyst dosage, PMS dosage, MNZ concentration, initial pH value, and various inorganic anions on the degradation efficiency of MNZ. The results demonstrated that NiCo@C-zeolite displayed outstanding efficacy in degrading MNZ under diverse conditions and maintained a degradation rate of 94.86% at 60 min after three consecutive cycles of degradation. Free radical quenching experiments revealed that SO•− 4 played a significant role in the presence of NiCo@C-zeolite-PMS system. These findings indicate that the novel rod-like NiCo-phyllosilicate hybrid catalysts had excellent performance in antibiotic degradation.

Electronic Structure Engineering of Pt-Ni Alloy NPs by Coupling of Gold Single Atoms on N-Doped Carbon for Highly Efficient Oxygen Reduction Reaction and Hydrogen Evolution Reaction.

Improving the catalytic activity and durability of platinum-based alloy catalysts remains a formidable challenge in the context of renewable energy electrolysis applications. Herein, a facile and rapid photochemical deposition strategy for the synthesis of gold single atoms (Au SAs) anchored on N-doped carbon is presented. These Au SAs serve as a charge redistribution support for Pt-Ni alloy nanoparticles (PtNiNPs/AuSA-NDC), creating an extended electron-donating interface with Pt-Ni alloy sites. Consequently, the PtNiNPs/AuSA-NDC hybrid catalyst manifests exceptional catalytic performance and durability in both the oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) under acidic conditions. Specifically, in ORR, it exhibits a half-wave potential (0.92V vs RHE), with a mass activity 20.4 times superior to Pt/C at 0.9V. In HER, PtNiNPs/AuSA-NDC demonstrates a notably reduced overpotential of 19.1mV vs RHE at 10mAcm-2 and a mass activity 38 times higher than Pt/C (at 0.25mV). Furthermore, this hybrid catalyst displays outstanding durability, with only an 8.0mV decay observed for ORR and a 6.9mV decay for HER after 10000 cycles. Theoretical calculations provide insight into the mechanism, demonstrating that isolated Au sites effectively modulate the electronic structure of Pt-Ni alloy sites, facilitating intermediate adsorption and enhancing reaction kinetics.

Rational design of multi-component Fe(OH)3/Ni-NiO heterostructures bifunctional catalyst for electrochemical water splitting

Exploring economic-efficient bifunctional catalysts is critical for the production of green hydrogen through water splitting. Herein, we fabricate a novel hybrid catalyst with three-phase heterojunction (Fe(OH)3/Ni-NiO) via a simple electrodeposition and chemical precipitation method. Benefiting from the desirable amorphous-crystal interfaces, the electronic structure of Ni, NiO and Fe(OH)3 is regulated, which will optimize the adsorption of H intermediates (H*) and also reduce the kinetic barrier for the hydrogen evolution reaction (HER). The optimal Fe(OH)3–3/Ni-NiO/CC shows superior bifunctional activity with low overpotentials of 66 mV for HER and 220 mV for OER at 10 mA cm−2 in alkaline solution, respectively, as well as remarkable durability over a period of 40 h. Besides, Fe(OH)3–3/Ni-NiO/CC requires 1.52 and 1.72 V to deliver 10 and 100 mA cm−2 and shows no obvious increase in current within 40 h toward overall water splitting. Experimental and theoretical results show that the HER process is promoted by the synergistic effect of electronic redistribution between Ni, NiO and Fe(OH)3 due to the construction of three phase crystalline-amorphous heterogeneous interface. Meanwhile, Fe(OH)3 and NiO appeared reconstruction, transforming into FeOOH and NiOOH during OER process, respectively. This work offers a simple synthesis method for designing bifunctional catalysts for water splitting.

Reinforcing the efficiency of photocatalytic CO2 conversion with H2O vapor through the integration of photothermal Cu/C@Bi/C supported on 3D g-C3N4 under full-spectrum solar irradiation

Developing an efficient photocatalyst for CO2 conversion to chemical fuels that maximizes the utilization of solar energy, particularly near-infrared light, remains a persistent challenge. Meanwhile, it is difficult to suppress the H2 evolution during the photocatalytic process. Herein, Cu/C@Bi/C grafted on the surface of 3D g-C3N4 (NCN) can serve as a highly durable and active catalyst for photothermal synergistic catalytic CO2 reduction under full-spectrum solar irradiation in solid-liquid-gas three-phase interfaces, wherein the Cu/C@Bi/C serves as a harvesting-near-infrared light nanoreactor and an electron transport bridge for the enhancement of the interface local temperature and the efficient transfer of photoinduced electrons. As a result, the hybrid catalyst shows excellent photothermal catalytic activity of CO2 to CO (169.26 μmol·g−1·h−1) and CO2 to CH4 (1.94 μmol·g−1·h−1), outperforming the majority of the conventional photocatalysts, whereas the competitive reaction of H2 evolution can be inhibited. This study presents a feasible approach for the efficient utilization of solar energy by harnessing near-infrared light through nano-reactors, thereby providing a viable strategy for photothermal catalytic CO2 reduction.

Single walled carbon nanotubes covalently functionalized by a ruthenium complex for photocatalytic oxidations

The covalent bonding of a ruthenium bipyridine complex derivative with the aromatic network of single walled carbon nanotubes (SWNT) through a stepwise protocol is presented, thus yielding the sample SWNT-Ru. To do that, an-amino decorated phenanthroline is bonded to the nanotube by means of the diazonium chemistry protocol, providing anchoring points for discrete organometallic units as depicted by the solid characterization techniques employed. The hybrid material, able to emit upon excitation, is active in the visible light-driven photocatalytic oxidation of organic sulfides to sulfoxides. SWNT-Ru presents a wide scope being able to convert more than 10 substrates with different characteristics, including added-value chemicals, with a stable performance over more than 6 cycles without metal leaching and enhanced activity compared to related homogeneous complexes. A versatile character is also demonstrated since this hybrid catalyst follows both possible photooxidation mechanisms.

Heteropolyacid promoted lignin-MOF derived spherical catalyst for catalytic hydrogen transfer of 5-hydroxymethylfurfural

Catalytic conversion of biomass-derived value-added chemicals was of great significance for the utilization of renewable biomass resources to instead of fossil chemicals. Biomass-derived lignin was regarded as an important support and 5-hydroxymethylfurfural (HMF) was a vital platform chemical derived from cellulose. Herein, a series of lignin-MOF hybrid catalysts were prepared and modified with different heteropolyacids (HPAs), which were then successfully introduced into the selective conversion of HMF to 5-hydroxymethylfurfuryl alcohol (MFA). The effect of different HPA, calcination temperature, etc. were all studied, and all catalysts were well characterized. It was confirmed that silicotungstic acid modified catalyst (Ni3Co-MOF-LS@HSiW) exhibited the best catalytic performance, while the highest conversion of HMF was up to 100%, with the best MFA yield of 86.5%. The finding in this study could provide novel insights for the utilization of lignin and preparation of value-added biomass-derived chemicals.

NHC-CDI Ligands Boost Multicarbon Production in Electrocatalytic CO2 Reduction by Increasing Accumulated Charged Intermediates and Promoting *CO Dimerization on Cu.

Copper-based materials exhibit significant potential as catalysts for electrochemical CO2 reduction, owing to their capacity to generate multicarbon hydrocarbons. The molecular functionalization of Cu electrodes represents a simple yet powerful strategy for improving the intrinsic activity of these materials by favoring specific reaction pathways through the creation of tailored microenvironments around the surface active sites. However, despite its success, comprehensive mechanistic insights derived from experimental techniques are often limited, leaving the active role of surface modifiers inconclusive. In this work, we show that N-heterocyclic carbene-carbodiimide-functionalized Cu catalysts display a remarkable activity for multicarbon product formation, surpassing bare Cu electrodes by more than an order of magnitude. These hybrid catalysts operate efficiently using an electrolyzer equipped with a gas diffusion electrode, achieving a multicarbon product selectivity of 58% with a partial current density of ca. -80 mA cm-2. We found that the activity for multicarbon product formation is closely linked to the surface charge that accumulates during electrocatalysis, stemming from surface intermediate buildup. Through X-ray photoelectron spectroscopy, we elucidated the role of the molecular additives in altering the electronic structure of the Cu electrodes, promoting the stabilization of surface CO. Additionally, in situ Raman measurements established the identity of the reaction intermediates that accumulate during electrocatalysis, indicating preferential CO binding on Cu step sites, known for facilitating C-C coupling. This study underscores the significant potential of molecular surface modifications in developing efficient electrocatalysts for CO2 reduction, highlighting surface charge as a pivotal descriptor of multicarbon product activity.