Promoting CO2 Dynamic Activation via Micro-Engineering Technology for Enhancing Electrochemical CO2 Reduction

Optimizing the coordination structure and microscopic reaction environment of isolated metal sites is promising for boosting catalytic activity for electrocatalytic CO₂ reduction reaction (CO₂RR) but is still challenging to achieve. Herein, a newly electrostatic induced self-assembly strategy for encapsulating isolated Ni-C₃N₁ moiety into hollow nano-reactor as I-Ni SA/NHCRs is developed, which achieves FE_CO of 94.91% at −0.80 V, the CO partial current density of ≈−15.35 mA cm⁻², superior to that with outer Ni-C₂N₂ moiety (94.47%, ≈−12.06 mA cm⁻²), or without hollow structure (92.30%, ≈−5.39 mA cm⁻²), and high FE_CO of ≈98.41% at 100 mA cm⁻² in flow cell. COMSOL multiphysics finite-element method and density functional theory (DFT) calculation illustrate that the excellent activity for I-Ni SA/NHCRs should be attributed to the structure-enhanced kinetics process caused by its hollow nano-reactor structure and unique Ni-C₃N₁ moiety, which can enrich electron on Ni sites and positively shift d-band center to the Fermi level to accelerate the adsorption and activation of CO₂ molecule and *COOH formation. Meanwhile, this strategy also successfully steers the design of encapsulating isolated iron and cobalt sites into nano-reactor, while I-Ni SA/NHCRs-based zinc-CO₂ battery assembled with a peak power density of 2.54 mW cm−⁻² is achieved.     

Ni Single Atoms Embedded in Graphene Nanoribbon Sieves for High-Performance CO2 Reduction to CO

Ni single-atom catalysts (SACs) are appealing for electrochemical reduction CO₂ reduction (CO₂RR). However, regulating the balance between the activity and conductivity remains a challenge to Ni SACs due to the limitation of substrates structure. Herein, the intrinsic performance enhancement of Ni SACs anchored on quasi-one-dimensional graphene nanoribbons (GNRs) synthesized is demonstrated by longitudinal unzipping carbon nanotubes (CNTs). The abundant functional groups on GNRs can absorb Ni atoms to form rich Ni–N₄–C sites during the anchoring process, providing a high intrinsic activity. In addition, the GNRs, which maintain a quasi-one-dimensional structure and possess a high conductivity, interconnect with each other and form a conductive porous framework. The catalyst yields a 44 mA cm⁻² CO partial current density and 96% faradaic efficiency of CO (FE_CO) at −1.1 V vs RHE in an H-cell. By adopting a membrane electrode assembly (MEA) flow cell, a 95% FE_CO and 2.4 V cell voltage are achieved at 200 mA cm⁻² current density. This work provides a rational way to synthesize Ni SACs with a high Ni atom loading, porous morphology, and high conductivity with potential industrial applications.     

Regulating the Electronic Structure of Bismuth Nanosheets by Titanium Doping to Boost CO2 Electroreduction and Zn–CO2 Batteries

The electrochemical carbon dioxide reduction reaction (E-CO₂RR) to formate is a promising strategy for mitigating greenhouse gas emissions and addressing the global energy crisis. Developing low-cost and environmentally friendly electrocatalysts with high selectivity and industrial current densities for formate production is an ideal but challenging goal in the field of electrocatalysis. Herein, novel titanium-doped bismuth nanosheets (Ti Bi NSs) with enhanced E-CO₂RR performance are synthesized through one-step electrochemical reduction of bismuth titanate (Bi₄Ti₃O₁₂). We comprehensively evaluated Ti Bi NSs using in situ Raman spectra, finite element method, and density functional theory. The results indicate that the ultrathin nanosheet structure of Ti Bi NSs can accelerate mass transfer, while the electron-rich properties can accelerate the production of *CO₂⁻ and enhance the adsorption strength of *OCHO intermediate. The Ti Bi NSs deliver a high formate Faradaic efficiency (FE_formate) of 96.3% and a formate production rate of 4032 µmol h⁻¹ cm⁻² at −1.01 V versus RHE. An ultra-high current density of −338.3 mA cm⁻² is achieved at −1.25 versus RHE, and simultaneously FE_formate still reaches more than 90%. Furthermore, the rechargeable Zn–CO₂ battery using Ti Bi NSs as a cathode catalyst achieves a maximum power density of 1.05 mW cm⁻² and excellent charging/discharging stability of 27 h.     

Geometric and Electronic Structural Engineering of Isolated Ni Single Atoms for a Highly Efficient CO2 Electroreduction

Tuning the coordination environment and geometric structures of single atom catalysts is an effective approach for regulating the reaction mechanism and maximize the catalytic efficiency of single-atom centers. Here, a template-based synthesis strategy is proposed for the synthesis of high-density NiN_x sites anchored on the surface of hierarchically porous nitrogen-doped carbon nanofibers (Ni-HPNCFs) with different coordination environments. First-principles calculations and advanced characterization techniques demonstrate that the single Ni atom is strongly coordinated with both pyrrolic and pyridinic N dopants, and that the predominant sites are stabilized by NiN₃ sites. This dual engineering strategy increases the number of active sites and utilization efficiency of each single atom as well as boosts the intrinsic activity of each active site on a single-atom scale. Notably, the Ni-HPNCF catalyst achieves a high CO Faradaic efficiency (FE_CO) of 97% at a potential of −0.7 V, a high CO partial current density (j_CO) of 49.6 mA cm⁻² (−1.0 V), and a remarkable turnover frequency of 24 900 h⁻¹ (−1.0 V) for CO₂ reduction reactions (CO₂RR). Density functional theory calculations show that compared to pyridinic-type NiN_x, the pyrrolic-type NiN₃ moieties display a superior CO₂RR activity over hydrogen evolution reactions, resulting in their superior catalytic activity and selectivity.     

InBi Bimetallic Sites for Efficient Electrochemical Reduction of CO2 to HCOOH

Formic acid is receiving intensive attention as being one of the most progressive chemical fuels for the electrochemical reduction of carbon dioxide. However, the majority of catalysts suffer from low current density and Faraday efficiency. To this end, an efficient catalyst of In/Bi-750 with InO_x nanodots load is prepared on a two-dimensional nanoflake Bi₂O₂CO₃ substrate, which increases the adsorption of ^*CO₂ due to the synergistic interaction between the bimetals and the exposure of sufficient active sites. In the H-type electrolytic cell, the formate Faraday efficiency (FE) reaches 97.17% at –1.0 V (vs reversible hydrogen electrode (RHE)) with no significant decay over 48 h. A formate Faraday efficiency of 90.83% is also obtained in the flow cell at a higher current density of 200 mA cm⁻². Both in-situ Fourier transform infrared spectroscopy (FT-IR) and theoretical calculations show that the BiIn bimetallic site can deliver superior binding energy to the ^*OCHO intermediate, thereby fundamentally accelerating the conversion of CO₂ to HCOOH. Furthermore, assembled Zn-CO₂ cell exhibits a maximum power of 6.97 mW cm⁻¹ and a stability of 60 h.     

Enhanced CO Affinity on Cu Facilitates CO2 Electroreduction toward Multi-Carbon Products

Electrochemical CO₂ reduction reaction (CO₂RR) is a promising strategy for waste CO₂ utilization and intermittent electricity storage. Herein, it is reported that bimetallic Cu/Pd catalysts with enhanced *CO affinity show a promoted CO₂RR performance for multi-carbon (C2+) production under industry-relevant high current density. Especially, bimetallic Cu/Pd-1% catalyst shows an outstanding CO₂-to-C2+ conversion with 66.2% in Faradaic efficiency (FE) and 463.2 mA cm⁻² in partial current density. An increment in the FE ratios of C2+ products to CO  for Cu/Pd-1% catalyst further illuminates a preferable C2+ production. In situ Raman spectra reveal that the atop-bounded CO is dominated by low-frequency band CO on Cu/Pd-1% that leads to C2+ products on bimetallic catalysts, in contrast to the majority of high-frequency band CO on Cu that favors the formation of CO. Density function theory calculation confirms that bimetallic Cu/Pd catalyst enhances the *CO adsorption and reduces the Gibbs free energy of the C C coupling process, thereby favoring the formation of C2+ products.     

Electroreduction of Carbon Dioxide Driven by the Intrinsic Defects in the Carbon Plane of a Single Fe–N4 Site

Manipulating the in‐plane defects of metal–nitrogen–carbon catalysts to regulate the electroreduction reaction of CO₂ (CO₂RR) remains a challenging task. Here, it is demonstrated that the activity of the intrinsic carbon defects can be dramatically improved through coupling with single‐atom Fe–N₄ sites. The resulting catalyst delivers a maximum CO Faradaic efficiency of 90% and a CO partial current density of 33 mA cm^?2 in 0.1 m KHCO_3. The remarkable enhancements are maintained in concentrated electrolyte, endowing a rechargeable Zn–CO₂ battery with a high CO selectivity of 86.5% at 5 mA cm^?2. Further analysis suggests that the intrinsic defect is the active sites for CO₂RR, instead of the Fe–N₄ center. Density functional theory calculations reveal that the Fe–N₄ coupled intrinsic defect exhibits a reduced energy barrier for CO₂RR and suppresses the hydrogen evolution activity. The high intrinsic activity, coupled with fast electron‐transfer capability and abundant exposed active sites, induces excellent electrocatalytic performance.     

A Carbon-Free and Free-Standing Cathode From Mixed-Phase TiO2 for Photo-Assisted Li–CO2 Battery

Li–CO₂ battery provides a new strategy to simultaneously solve the problems of energy storage and greenhouse effect. However, the severe polarization of CO₂ reduction and CO₂ evolution reaction impede the practical application. Herein, anodic TiO₂ nanotube arrays are first introduced as carbon-free and free-standing cathode for photo-assisted Li–CO₂ battery, and the photo-assisted charge and discharge mechanism is first clarified from the perspective of photocatalysis. Mixed-phase TiO₂ exhibits a long cycling life of 580 h (52 cycles) at 0.025 mA cm⁻² and delivers a high discharge specific capacity of 3001 µAh cm⁻² under UV illumination. The charge voltage dramatically reduces from 4.53 to 3.03 V under UV illumination. The improvement of photo-assisted Li–CO₂ battery performance relies on the synergistic effect of the hierarchical porous structure, strong UV absorption, efficient separation, and transfer of photo-generated electrons and holes at hetero-phase junction, and the facilitation of photo-generated electrons and holes on CO₂ reduction and CO₂ evolution reaction. This work can provide useful guidance for designing efficient photocathode for photo-assisted Li–CO₂ battery and other metal–air batteries.     

Cu?C(O) Interfaces Deliver Remarkable Selectivity and Stability for CO2 Reduction to C2+ Products at Industrial Current Density of 500 mA cm−2

The electrocatalytic CO₂ reduction reaction (CO₂RR) is an attractive technology for CO₂ valorization and high-density electrical energy storage. Achieving a high selectivity to C₂₊ products, especially ethylene, during CO₂RR at high current densities (>500 mA cm⁻²) is a prized goal of current research, though remains technically very challenging. Herein, it is demonstrated that the surface and interfacial structures of Cu catalysts, and the solid–gas–liquid interfaces on gas-diffusion electrode (GDE) in CO₂ reduction flow cells can be modulated to allow efficient CO₂RR to C₂₊ products. This approach uses the in situ electrochemical reduction of a CuO nanosheet/graphene oxide dots (CuO C(O)) hybrid. Owing to abundant Cu O C interfaces in the CuO C(O) hybrid, the CuO nanosheets are topologically and selectively transformed into metallic Cu nanosheets exposing Cu(100) facets, Cu(110) facets, Cu[n(100) × (110)] step sites, and Cu⁺/Cu⁰ interfaces during the electroreduction step,  the faradaic efficiencie (FE) to C₂₊ hydrocarbons was reached as high as 77.4% (FE_ethylene ≈ 60%) at 500 mA cm⁻² . In situ infrared spectroscopy and DFT simulations demonstrate that abundant Cu⁺ species and Cu⁰/Cu⁺ interfaces in the reduced CuO C(O) catalyst improve the adsorption and surface coverage of *CO on the Cu catalyst, thus facilitating C C coupling reactions.     

High-Dispersive Pd Nanoparticles on Hierarchical N-Doped Carbon Nanocages to Boost Electrochemical CO2 Reduction to Formate at Low Potential

Electrochemical CO₂ reduction reaction (CO₂RR) to value-added chemicals/fuels is an effective strategy to achieve the carbon neutral. Palladium is the only metal to selectively produce formate via CO₂RR at near-zero potentials. To reduce cost and improve activity, the high-dispersive Pd nanoparticles on hierarchical N-doped carbon nanocages (Pd/hNCNCs) are constructed by regulating pH in microwave-assisted ethylene glycol reduction. The optimal catalyst exhibits high formate Faradaic efficiency of >95% within −0.05–0.30 V and delivers an ultrahigh formate partial current density of 10.3 mA cm⁻² at the low potential of −0.25 V. The high performance of Pd/hNCNCs is attributed to the small size of uniform Pd nanoparticles, the optimized intermediates adsorption/desorption on modified Pd by N-doped support, and the promoted mass/charge transfer kinetics arising from the hierarchical structure of hNCNCs. This study sheds light on the rational design of high-efficient electrocatalysts for advanced energy conversion.     

Boron bridged NiN4B2Cx single-atom catalyst for superior electrochemical CO2 reduction

Single-atom nickel catalysts hold great promise in the application of electrocatalytic carbon dioxide reduction reaction (CO₂RR), but suffer from the sluggish kinetics and serious competitive hydrogen evolution reaction (HER), which restrict their overall catalytic performance. Herein, we report a boron-bridging strategy to manipulate the atomic coordination structure and construct a single-atom nickel catalyst with an active center of NiN₄B₂ to realize excellent CO₂RR performance. Density functional theory analysis suggests that the unique NiN₄B₂ sites with tuned electronic structure facilitate the adsorption of CO₂ molecules and effectively suppress the HER pathway by increasing corresponding energy barrier. As-obtained Ni-SAs@BNC catalyst with a NiN₄B₂ structure exhibits significantly enhanced catalytic activity and selectivity than commonly used single-atom nickel catalysts with a NiN₄ structure, especially at high applied potentials. A high current density of up to (214 ± 21) mA cm⁻² at a potential of −1.2 V with a high CO Faraday efficiency (FE_CO) of ∼97% was achieved in a flow cell. This work inspires new insights into the rational design of atomic coordination structure of single-atom catalysts with tunable electronic structure for superior electrocatalytic activities.     

Catalytic Hydrogenation of CO2 to Formate Using Ruthenium Nanoparticles Immobilized on Supported Ionic Liquid Phases

Ruthenium nanoparticles (NPs) immobilized on imidazolium-based supported ionic liquid phases (Ru@SILP) act as effective heterogeneous catalysts for the hydrogenation of carbon dioxide (CO₂) to formate in a mixture of water and triethylamine (NEt₃). The structure of the imidazolium-based molecular modifiers is varied systematically regarding side chain functionality (neutral, basic, and acidic) and anion to assess the influence of the IL-type environment on the NPs synthesis and catalytic properties. The resulting Ru@SILP materials contain well-dispersed Ru NPs with diameters in the range 0.8–2.9 nm that are found 2 to 10 times more active for CO₂ hydrogenation than a reference Ru@SiO₂ catalyst under identical conditions. Introduction of sulfonic acid groups in the IL modifiers results in a greatly increased turnover number (TON) and turnover frequency (TOF) at reduced metal loadings. As a result, excellent productivity with TONs up to 16 100 at an initial TOF of 1430 h⁻¹ can be achieved with the Ru@SILP(SO₃H-OAc) catalyst. H/D exchange and other control experiments suggest an accelerated desorption of the formate species from the Ru NPs promoted by the presence of ammonium sulfonate species on Ru@SILP(SO₃H-X) materials, resulting in enhanced catalyst activity and productivity.     

Encapsulating Ni Nanoparticles into Interlayers of Nitrogen-Doped Nb2CTx MXene to Boost Hydrogen Evolution Reaction in Acid

Design and development of low-cost and highly efficient non-precious metal electrocatalysts for hydrogen evolution reaction (HER) in an acidic medium are key issues to realize the commercialization of proton exchange membrane water electrolyzers. Ni is regarded as an ideal alternative to substitute Pt for HER based on the similar electronic structure and low price as well. However, low intrinsic activity and poor stability in acid restrict its practical applications. Herein, a new approach is reported to encapsulate Ni nanoparticles (NPs) into interlayer edges of N-doped Nb₂CT_x MXene (Ni NPs@N-Nb₂CT_x) by an electrochemical process. The as-prepared Ni NPs@N-Nb₂CT_x possesses Pt-like onset potentials and can reach 500 mA cm⁻² at overpotentials of only 383 mV, which is much higher than that of N-Nb₂CT_x supported Ni NPs synthesized by a wet-chemical method (w- Ni NPs/N-Nb₂CT_x). Furthermore, it shows high durability toward HER with a large current density of 300 mA cm⁻² for 24 h because of the encapsulated structure against corrosion, oxidation as well as aggregation of Ni NPs in an acidic medium. Detailed structural characterization and density functional theory calculations reveal that the stronger interaction boosts the HER.     

One-Step Phase Separation for Core-Shell Carbon@Indium Oxide@Bismuth Microspheres with Enhanced Activity for CO2 Electroreduction to Formate

It is a substantial challenge to construct electrocatalysts with high activity, good selectivity, and long-term stability for electrocatalytic reduction of carbon dioxide to formic acid. Herein, bismuth and indium species are innovatively integrated into a uniform heterogeneous spherical structure by a neoteric quasi-microemulsion method, and a novel C@In₂O₃@Bi₅₀ core-shell structure is constructed through a subsequent one-step phase separation strategy due to melting point difference and Kirkendall effect with the nano-limiting effect of the carbon structure. This core-shell C@In₂O₃@Bi₅₀ catalyst can selectively reduce CO₂ to formate with high selectivity (≈90% faradaic efficiency), large partial current density (24.53 mA cm⁻² at −1.36 V), and long-term stability (up to 14.5 h), superior to most of the Bi-based catalysts. The hybrid Bi/In₂O₃ interfaces of core-shell C@In₂O₃@Bi will stabilize the key intermediate HCOO* and suppress CO poisoning, benefiting the CO₂RR selectivity and stability, while the internal cavity of core-shell structure will improve the reaction kinetics because of the large specific surface area and the enhancement of ion shuttle and electron transfer. Furthermore, the nano-limited domain effect of outmost carbon prevent active components from oxidation and agglomeration, helpful for stabilizing the catalyst. This work offers valuable insights into core-shell structure engineering to promote practical CO₂ conversion technology.     

Regulation of Electrocatalytic Behavior by Axial Oxygen Enhances the Catalytic Activity of CoN4 Sites for CO2 Reduction

Recent studies have found that the existence of oxygen around the active sites may be essential for efficient electrochemical CO₂-to-CO conversion. Hence, this work proposes the modulation of oxygen coordination and investigates the as-induced catalytic behavior in CO₂RR. It designs and synthesizes conjugated phthalocyanine frameworks catalysts (CPF-Co) with abundant CoN₄ centers as an active source, and subsequently modifies the electronic structure of CPF-Co by introducing graphene oxide (GO) with oxygen-rich functional groups. A systematic study reveals that the axial coordination between oxygen and the catalytic sites could form an optimized O-CoN₄ structure to break the electron distribution symmetry of Co, thus reducing the energy barrier to the activation of CO₂ to COOH*. Meanwhile, by adjusting the content of oxygen, the proper supports can also facilitate the charge transfer efficiency between the matrix layer and the catalytic sites. The optimized CPF-Co@LGO exhibits a high TOF value (2.81 s⁻¹), CO selectivity (97.6%) as well as stability (24 h) at 21 mA cm⁻² current density. This work reveals the modulation of oxygen during CO₂RR and provides a novel strategy for the design of efficient electrocatalysts, which may inspire new exploration and principles for CO₂RR.     

Promoting Electrocatalytic CO2 Reduction to CH4 by Copper Porphyrin with Donor–Acceptor Structures

Molecular catalysts have been receiving increasingly attention in the electrochemical CO₂ reduction reaction (CO₂RR) with attractive features such as precise catalytic sites and tunable ligands. However, the insufficient activity and low selectivity of deep reduction products restrain the utilization of molecular catalysts in CO₂RR. Herein, a donor–acceptor modified Cu porphyrin (CuTAPP) is developed, in which amino groups are linked to donate electrons toward the central CuN₄ site to enhance the CO₂RR activity. The CuTAPP catalyst exhibited an excellent CO₂-to-CH₄ electroreduction performance, including a high CH₄ partial current density of 290.5 mA cm⁻² and a corresponding Faradaic efficiency of 54.8% at –1.63 V versus reversible hydrogen electrode in flow cells. Density functional theory calculations indicated that CuTAPP presented a much lower energy gap in the pathway of producing *CHO than Cu porphyrin without amino group modification. This work suggests a useful strategy of introducing designed donor–acceptor structures into molecular catalysts for enhancing electrochemical CO₂ conversion toward deep reduction products.     

Multilayer-Cavity Tandem Catalyst for Profiling Sequentially Coupling of Intermediate CO in Electrocatalytic Reduction Reaction of CO2 to Multi-Carbon Products

Electrochemical CO₂ reduction reaction (CO₂RR) is an effective approach to address CO₂ emission, promote recycling, and synthesize high-value multi-carbon (C₂₊) chemicals for storing renewable electricity in the long-term. The construction of multilayer-bound nanoreactors to achieve management of intermediate CO is a promising strategy for tandem to C₂₊ products. In this study, a series of Ag@Cu₂O nanoreactors consisting of an Ag-yolk and a multilayer confined Cu shell is designed to profile electrocatalytic CO₂RR reactions. The optimized Ag@Cu₂O-2 nanoreactor exhibits a 74% Faradaic efficiency during the C₂₊ pathway and remains stable for over 10 h at a bias current density of 100 mA cm⁻². Using the finite element method, this model determines that the certain volume of cavity in the Ag@Cu₂O nanoreactors facilitates on-site CO retention and that multilayers of Cu species favor CO capture. Density functional theory calculations illustrate that the biased generation of ethanol products may arise from the (100)/(111) interface of the Cu layer. In-depth explorations in multilayer-bound nanoreactors provide structural and interfacial guidance for sequential coupling of CO₂RR intermediates for efficient C₂₊ generation.     

Constructing Co@TiO2 Nanoarray Heterostructure with Schottky Contact for Selective Electrocatalytic Nitrate Reduction to Ammonia

Electrochemical nitrate (NO₃⁻) reduction reaction (NO₃⁻RR) is a potential sustainable route for large-scale ambient ammonia (NH₃) synthesis and regulating the nitrogen cycle. However, as this reaction involves multi-electron transfer steps, it urgently needs efficient electrocatalysts on promoting NH₃ selectivity. Herein, a rational design of Co nanoparticles anchored on TiO₂ nanobelt array on titanium plate (Co@TiO₂/TP) is presented as a high-efficiency electrocatalyst for NO₃⁻RR. Density theory calculations demonstrate that the constructed Schottky heterostructures coupling metallic Co with semiconductor TiO₂ develop a built-in electric field, which can accelerate the rate determining step and facilitate NO₃⁻ adsorption, ensuring the selective conversion to NH₃. Expectantly, the Co@TiO₂/TP electrocatalyst attains an excellent Faradaic efficiency of 96.7% and a high NH₃ yield of 800.0 µmol h⁻¹ cm⁻² under neutral solution. More importantly, Co@TiO₂/TP heterostructure catalyst also presents a remarkable stability in 50-h electrolysis test.     

High-Performance Li-CO2 Battery Based on Carbon-Free Porous Ru@QNFs Cathode

Lithium-carbon dioxide (Li-CO₂) batteries have attracted much attention due to their high theoretical energy density. However, due to the existance of lithium carbonate and amorphous carbon in the discharge products that are difficult to decompose, the battery shows low coulombic efficiency and poor cycle performance. Here, by adjusting the adsorption of carbon dioxide (CO₂) on ruthenium (Ru) catalysts surface, this work reports an ultralow charge overpotential and long cycle life Li-CO₂ battery that consists of typical lithium metal, ternary molten salt electrolyte (TMSE), and Ru-based cathode. Experimental results show that the Ru catalysts deposited on quartz nanofiber (QF) can suppress the four-electron conversion of CO₂ to lithium carbonate (Li₂CO₃). As a result, the battery shows a long-cycle-life of over 457 cycles at 1.0 A g⁻¹ with a limited capacity of 500 mAh g⁻¹_Ru. Remarkably, a recorded low discharge potential of ≈3.0 V has been achieved after 35 cycles at 0.5 A g⁻¹, with a charge potential retention of over 99%. Moreover, the battery can operate over 25 A g⁻¹ and recover 96% potential. This battery technology paves the way for designing high-performance rechargeable Li-CO₂ batteries with carbon neutrality.     

Synergistic Functionality of Dopants and Defects in Co-Phthalocyanine/B-CN Z-Scheme Photocatalysts for Promoting Photocatalytic CO2 Reduction Reactions

The realization of solar-light-driven CO₂ reduction reactions (CO₂ RR) is essential for the commercial development of renewable energy modules and the reduction of global CO₂ emissions. Combining experimental measurements and theoretical calculations, to introduce boron dopants and nitrogen defects in graphitic carbon nitride (g-C₃N₄), sodium borohydride is simply calcined with the mixture of g-C₃N₄ (CN), followed by the introduction of ultrathin Co phthalocyanine through phosphate groups. By strengthening H-bonding interactions, the resultant CoPc/P-BNDCN nanocomposite showed excellent photocatalytic CO₂ reduction activity, releasing 197.76 and 130.32 µmol h⁻¹ g⁻¹ CO and CH₄, respectively, and conveying an unprecedented 10-26-time improvement under visible-light irradiation. The substantial tuning is performed towards the conduction and valance band locations by B-dopants and N-defects to modulate the band structure for significantly accelerated CO₂ RR. Through the use of ultrathin metal phthalocyanine assemblies that have a lot of single-atom sites, this work demonstrates a sustainable approach for achieving effective photocatalytic CO₂ activation. More importantly, the excellent photoactivity is attributed to the fast charge separation via Z-scheme transfer mechanism formed by the universally facile strategy of dimension-matched ultrathin (≈4 nm) metal phthalocyanine-assisted nanocomposites.