Catalysts For CO2 Reduction Research Articles

Direct parallel electrosynthesis of high-value chemicals from atmospheric components on symmetry-breaking indium sites

To tackle significant environmental and energy challenges from increased greenhouse gas emissions in the atmosphere, we propose a method that synergistically combines cost-efficient integrated systems with parallel catalysis to produce high-value chemicals from CO2, NO, and other gases. We employed asymmetrically stretched InO5S with symmetry-breaking indium sites as a highly efficient trifunctional catalysts for NO reduction, CO2 reduction, and O2 reduction. Mechanistic studies reveal that the symmetry-breaking at indium sites substantially improves d-band center interactions and adsorption of intermediates, thereby enhancing trifunctional catalytic activity. Employed in a flow electrolysis system, the catalyst achieves continuous and flexible production of NH3, HCOO-, and H2O2, maintaining over 90% Faradaic efficiency at industrial scales. Notably, the parallel electrolysis device reported in this study effectively produces high-value products like NH4COOH directly from greenhouse gases in pure water, offering an economically efficient solution for small molecule synthesis and unique insights for the sustainable conversion of inexhaustible gases into valuable products. Therefore, this work possesses considerable potential for future practical applications in sustainable industrial processes.

Surface Sulfurization of Cubic Cu2O to Form Cu2S Nanostructure-Decorated Catalysts for Light-enhanced Electrocatalytic H2 Evolution and Photocatalytic CO2 Reduction.

Developing highly efficient bifunctional catalysts for electrocatalysis and photocatalysis suffers from sluggish charge transfer and poor photo-to-electric conversion rate. Herein, micro-sized Cu2O cubes were initially prepared for subsequent transformation into Cu2O@Cu2S core-shell structures by a slight surface sulfurization. The formation of nanostructured Cu2S thin layer at Cu2O surface can endow an immediate charge separation and migration under light irradiation, leading to high surface photovoltages (SPV, 18-30 mV). As a result, the as-prepared Cu2O@Cu2S catalysts exhibited reduced overpotentials (η, only 86 mV is required for the optimized sample to achieve a current density of 10 mA cm-2) for H2 evolution with good cycling stability in electrocatalytic water splitting. Meanwhile, a high methane (CH4) production rate of 30.3 μmol h-1 g-1 can be delivered from the optimized Cu2O@Cu2S sample when used for photocatalytic CO2 reduction. This work has provided a strategy to prepare bifunctional catalysts with improved photoelectric properties for photo/electrocatalytic applications.

Tuning the Electronic Properties of CumAgn Bimetallic Clusters for Enhanced CO2 Activation

The urgent demand for efficient CO2 reduction technologies has driven enormous studies into the enhancement of advanced catalysts. Here, we investigate the electronic properties and CO2 adsorption properties of CumAgn bimetallic clusters, particularly Cu4Ag1, Cu1Ag4, Cu3Ag2, and Cu2Ag3, using generalized gradient approximation (GGA)/density functional theory (DFT). Our results show that the atomic arrangement within these clusters drastically affects their stability, charge transfer, and catalytic performance. The Cu4Ag1 bimetallic cluster emerges as the most stable structure, revealing superior charge transfer and effective chemisorption of CO2, which promotes effective activation of the CO2 molecule. In contrast, the Cu1Ag4 bimetallic cluster, in spite of comparable adsorption energy, indicates insignificant charge transfer, resulting in less pronounced CO2 activation. The Cu3Ag2 and Cu2Ag3 bimetallic clusters also display high adsorption energies with remarkable charge transfer mechanisms, emphasizing the crucial role of metal composition in tuning catalytic characteristics. This thorough examination provides constructive insights into the design of bimetallic clusters for boosted CO2 reduction. These findings could pave the way for the development of cost-effective and efficient catalysts for industrial CO2 reduction, contributing to global efforts in carbon management and climate change mitigation.

A Highly Conjugated Nickel(II)‐Acetylide Framework for Efficient Photocatalytic Carbon Dioxide Reduction

AbstractThe incorporation of transition‐metal single atoms as molecular functional entities into the skeleton of graphdiyne (GDY) to construct novel two‐dimensional (2D) metal‐acetylide frameworks, known as metalated graphynes (MGYs), is a promising strategy for developing efficient catalysts, which can combine the tunable charge transfer of GDY frameworks, the catalytic activity of metal and the precise distribution of single metallic centers. Herein, four highly conjugated MGY photocatalysts based on NiII, PdII, PtII, and HgII were synthesized for the first time using the ‘bottom‐up’ strategy through the use of M−C bonds (−C≡C−M−C≡C−). Remarkably, the NiII‐based graphyne (TEPY‐Ni‐GY) exhibited the highest CO generation rate of 18.3 mmol g−1 h−1 and a selectivity of 98.8 %. This superior performance is attributed to the synergistic effects of pyrenyl and −C≡C−Ni(PBu3)2−C≡C– moieties. The pyrenyl block functions as an intramolecular π‐conjugation channel, facilitating kinetically favorable electron transfer, while the −C≡C−Ni(PBu3)2−C≡C− moiety serves as the catalytic site that enhances CO2 adsorption and activation, thereby suppressing competitive hydrogen evolution. This study provides a new perspective on MGY‐based photocatalysts for developing highly active and low‐cost catalysts for CO2 reduction.

Selenic Acid Etching Assisted Atomic Engineering for Designing Metal-Semimetal Dual Single-Atom Catalysts for Enhanced CO2 Electroreduction.

Single-atom catalysts are promising for electrocatalytic CO2 conversion but face challenges in controllable syntheses. Herein, a facile selenic acid etching-assisted strategy has been developed to fabricate a hybrid metal-semimetal dual single-atom catalyst for electrocatalytic CO2 reduction. This strategy enables the simultaneous generation of monodisperse active sites and hierarchical morphologies with hollow nanostructures. The as-obtained catalyst with Fe-Se dual single-atom sites supported by porous nitrogen-doped carbon (FeSe-NC) shows exceptional catalytic activity and CO selectivity, delivering a Faradaic efficiency (FE) of >97% with industrially comparable jCO, superior to the Fe single-atom catalyst. Moreover, the FeSe-NC-based rechargeable Zn-CO2 battery delivers a high power density (2.01 mW cm-2) and outstanding FECO (>90%), as well as excellent cycling stability. Experimental results together with theoretical calculations reveal that the etching-induced defects and the Se-modulated Fe centers with asymmetrical polarized charge distributions synergistically facilitate the key intermediate *CO desorption and thus accelerate the CO2-to-CO conversion.

The effect of carbon supports on the electrocatalytic performance of Ni-N-C catalysts for CO2 reduction to CO

Carbon-supported nickel and nitrogen co-doped (Ni-N-C) catalysts have been extensively studied as selective and active catalysts for CO2 electroreduction to CO. Most studies have focused on adjusting the coordination structure of Ni-Nx active sites, while the impact of the carbon supports has often been overlooked. In this study, a series of Ni-N-C catalysts on different carbon supports, including carbon black (CB), multi-walled carbon nanotubes (CNT), and activated nitrogen-doped biochar (ANBC), were synthesized using a ligand-mediated method. The effect of the carbon support on the electrocatalytic performance for CO2 reduction was investigated at both low current densities, in a H-cell, and high current densities, in a MEA electrolyzer. All of the prepared Ni-N-C catalysts show good faradaic efficiencies (FE) toward CO production (up to ~90%), however, the onset potentials and partial current densities for CO production vary greatly. The textural properties of the carbon support and the distribution of Ni-Nx active sites on the carbon support are demonstrated as the main factors behind the performance differences. In particular, hierarchical porous structures with large specific surface area are helpful to facilitate mass transport and improve the dispersion of active sites, which allows for a better CO2 reduction performance of Ni-N-ANBC compared to Ni-N-CB and Ni-N-CNT. This study demonstrates the importance of the carbon support for Ni-N-C catalysts and provides new insights into the design of efficient Ni-N-C catalysts for the CO2RR.

TM@MoSSe (TM = Ni, Fe) as novel electrocatalysts for reduction of CO2 to CO: A DFT study

It is crucial to develop highly efficient, selective and low-overpotential electrocatalysts for CO2 reduction. This paper proposes an efficient iron and nickel single-atom catalyst using Janus MoSSe as the substrate to reduce CO2 to CO by using DFT calculations. The adsorption of a single TM atom like Fe, Co, Ni, Ru, Rh, Pd, Os, Ir and Pt on Janus MoSSe monolayer results in a decrease in band gap, which may accelerate the catalytic CO2 reduction. The excellent catalytic activity of Fe@MoSSe and Ni@MoSSe is owing to the high d-band center and hence the strong TM-CO2 bonding. The asymmetric structure of Janus MoSSe creates the local built-in electric field, which further increases by about 8% or 0.8% after the adsorption of single Ni or Fe atom so as to afford the better electrocatalytic performances for reduction of CO2 to CO in both TM modified systems. So, this work proposes the catalysts Fe@MoSSe and Ni@MoSSe with good selectivity and activity for CO2 reduction by revealing their underlying mechanisms, and Janus MoSSe may be used as a potential substrate material for CO2 reduction catalysts.

AuAg plasmonic nanoalloys with asymmetric charge distribution on CeO2 nanorods for selective photocatalytic CO2‐to‐CH4 conversion

AbstractConverting CO2 under mild conditions by employing semiconductor photocatalysts is promising to address global environmental issues. However, the current CO2 conversion efficiency is limited by the difficulty activating the thermodynamically stable CO2 molecules. Constructing plasmonic nanoalloy‐based photocatalytic systems with significant localized surface plasmon resonance (LSPR) is full of potential but remains a vast challenge. In this work, AuAg plasmonic nanoalloys were incorporated on CeO2 nanorods (designated as AuAg–CeO2) to achieve selective photoreduction of CO2. The result displays that Ag can serve as a superior electron modifier to promote the electron enrichment of Au, thus producing asymmetric charge distributions to boost the selective conversion of CO2. Furthermore, the improved LSPR effect on AuAg–CeO2 induces the generation of high‐energy hot electrons under irradiation, enhancing the reactivity of electrons for CO2 photoreduction. Due to the aforementioned effects, AuAg–CeO2 exhibits a high CO2‐to‐CH4 performance of 92.6 μmol g−1 through a 3‐h test and a high CH4 selectivity of 94.5%, up to 2.6, 8.7, and 17.1 times higher than the activity of Au–CeO2, pure CeO2, and Ag–CeO2, respectively. This work can provide a new perspective for constructing high‐performance catalysts for photocatalytic CO2 reduction.

Delocalization State-Stabilized Znδ+ Active Sites for Highly Selective and Durable CO2 Electroreduction.

Zinc (Zn)-based materials are cost-effective and promising single-metal catalysts for CO2 electroreduction to CO but is still challenged by low selectivity and long-term stability. Undercoordinated Zn (Znδ+) sites have been demonstrated to be powerful active centers with appropriate *COOH affinity for efficient CO production However, electrochemical reduction conditions generally cause the inevitable reduction of Znδ+, resulting in the decline of CO efficiency over prolonged operation. Herein, a Zn cyanamide (ZnNCN) catalyst is constructed for highly selective and durable CO2 electroreduction, wherein the delocalized Zn d-electrons and resonant structure of cyanamide ligand prevent the self-reduction of ZnNCN and maintain Znδ+ sites under cathodic conditions. The mechanism studies based on density functional theory and operando spectroscopies indicate that delocalized Znδ+ site can stabilize the key *COOH intermediate through hard-soft acid-base theory, therefore thermodynamically promoting CO2-to-CO conversion. Consequently, ZnNCN delivers a CO Faradaic efficiency (FE) of up to 93.9% and further exhibits a remarkable stability lifespan of 96h, representing a significant advancement in developing robust Zn-based electrocatalysts. Beyond expanding the variety of CO2 reduction catalysts, this work also offers insights into understanding the structure-function sensitivity and controlling dynamic active sites.

A Regenerable Bi-Based Catalyst for Efficient and Stable Electrochemical CO2 Reduction to Formate at Industrial Current Densities.

Renewable electricity shows immense potential as a driving force for the carbon dioxide reduction reaction (CO2RR) in production of formate (HCOO-) at industrial current density, providing a promising path for value-added chemicals and chemical manufacturing. However, achieving high selectivity and stable production of HCOO- at industrial current density remains a challenge. Here, we present a robust Bi0.6Cu0.4 NSs catalyst capable of regenerating necessary catalytic core (Bi-O) through cyclic voltammetry (CV) treatment. Notably, at 260 mA cm-2, faradaic efficiency of HCOO- reaches an exceptional selectivity to 99.23 %, maintaining above 90 % even after 400 h, which is longest reaction time reported at the industrial current density. Furthermore, in stability test, the catalyst was constructed by CV reconstruction to achieve stable and efficient production of HCOO-. In 20 h reaction test, the catalyst has a rate of HCOO- production of 13.24 mmol m-2 s-1, a HCOO- concentration of 1.91 mol L-1, and an energy consumption of 129.80 kWh kmol-1. In situ Raman spectroscopy reveals the formation of Bi-O structure during the gradual transformation of catalyst from Bi0.6Cu0.4 NBs to Bi0.6Cu0.4 NSs. Theoretical studies highlight the pivotal role of Bi-O structure in modifying the adsorption behavior of reaction intermediates, which further reduces energy barrier for *OCHO conversion in CO2RR.

P-Block Aluminum Single-Atom Catalyst for Electrocatalytic CO2 Reduction with High Intrinsic Activity.

Atomically dispersed transition metal sites on nitrogen-doped carbon catalysts hold great potential for the electrochemical CO2 reduction reaction (CO2RR) to CO due to their encouraging selectivity. However, their intrinsic activity is restricted by the hurdle of the high energy barrier of either *COOH formation or *CO desorption due to the scaling relationship. Herein, we discover a p-block aluminum single-atom catalyst (Al-NC) featuring an Al-N4 site that enables disentangling this hurdle, which endows a moderate reaction kinetic barrier for *COOH formation and *CO desorption, as validated by in situ attenuated total reflection infrared spectroscopy and theoretical simulations. As a result, the developed Al-NC shows a CO Faradaic efficiency (FECO) of up to 98.76% at -0.65 V vs RHE and an intrinsic catalytic turnover frequency of 3.60 s-1 at -0.99 V vs RHE, exceeding those of the state-of-the-art Ni-NC and Fe-NC counterparts. Moreover, it also delivers a partial CO current of 309 mA·cm-2 at 93.65% FECO and 605 mA at >85% FECO in a flow cell and membrane electrode assembly (MEA), respectively. Strikingly, when using low-concentration CO2 (30%) as the feedstock, this catalyst can still deliver a partial CO current of 240 mA at >80% FECO in the MEA. Considering the earth-abundant character of the Al element and the high intrinsic activity of the Al-NC catalyst, it is a promising alternative to today's transition metal-based single-atom catalysts.

Heterobimetallic NiFe Complex for Photocatalytic CO2 Reduction: United Efforts of NiFe Dual Sites.

Catalytic CO2 reduction poses a significant challenge for the conversion of CO2 into chemicals and fuels. Ni-Fe carbon monoxide dehydrogenase ([NiFe]-CODH) effectively mediates the reversible conversion of CO2 and CO at a nearly thermodynamic equilibrium potential, highlighting the heterobimetallic cooperation for the design of CO2 reduction catalysts. However, numerous NiFe biomimetic model complexes have realized little success in CO2 reduction catalysis, which underscores the crucial role of precise bimetallic configuration and functionality. Herein, we presented a heterobimetallic NiFe complex for the photocatalytic reduction of CO2 to CO, demonstrating significantly enhanced catalytic performance compared to the homonuclear NiNi catalyst. Photocatalytic and mechanistic investigations revealed that with the assistance of a redox-active phenanthroline ligand, NiFe achieves dual-site activation of CO2 through a pivotal intermediate, NiII(μ-CO22--κC:κO)FeII, where the Lewis acidity of the FeII site plays an important role, as corroborated in the homonuclear FeFe system. This study introduces the first heteronuclear NiFe molecular catalyst capable of efficiently catalyzing the reduction of CO2 to CO, deepening insights into heterobimetallic cooperation and offering a novel strategy for designing highly active and selective CO2 reduction catalysts.

Enhanced photocatalytic CO2 reduction to CH4 on oxygen vacancy-rich NiCo2O4 with surface pits: Synthesis, DFT calculations, and mechanistic insights

Unraveling the influence of surface microstructure in materials on their interaction with CO2 remains a critical challenge in achieving efficient and selective CO2 reduction. In this study, we report the engineering of pit structures on the NiCo2O4 surface for efficient photocatalytic reduction of CO2. Characterization results show that calcination temperature affects the distribution of surface pits and oxygen vacancy concentration. Oxygen vacancy sites accompanying surface pits facilitate the generation and movement of photogenerated electrons and holes, preventing their recombination and promoting the conversion of CO2. The CH4 yield from photocatalytic CO2 reduction reaches 52.4 μmol g−1 with the optimal pitted NiCo2O4 catalyst (PNCO2), significantly surpassing the 18.4 μmol g−1 yield of non-pitted NiCo2O4 (NPNCO). Additionally, PNCO2 improves selectivity from 81.8 % for NPNCO to 94.1 %. Density functional theory calculations show that CO2 adsorption on the PNCO2 surface is significantly enhanced as the d-band center shifts toward the Fermi level. The adsorbed CO2 combines with electrons enriched at the Ni sites at the edges of the surface pits, leading to further activation. The reduction of CO2 to intermediate products such as CHO* is analyzed based on in situ diffuse reflectance infrared Fourier transform spectroscopy, and a possible reaction pathway is proposed. This work offers fresh insights into engineering surface pit structures for the design and synthesis of catalysts for photocatalytic CO2 reduction.

A Highly Conjugated Nickel(II)-Acetylide Framework for Efficient Photocatalytic Carbon Dioxide Reduction.

The incorporation of transition-metal single atoms as molecular functional entities into the skeleton of graphdiyne (GDY) to construct novel two-dimensional (2D) metal-acetylide frameworks, known as metalated graphynes (MGYs), is a promising strategy for developing efficient catalysts, which can combine the tunable charge transfer of GDY frameworks, the catalytic activity of metal and the precise distribution of single metallic centers. Herein, four highly conjugated MGY photocatalysts based on NiII, PdII, PtII, and HgII were synthesized for the first time using the 'bottom-up' strategy through the use of M-C bonds (-C≡C-M-C≡C-). Remarkably, the NiII-based graphyne (TEPY-Ni-GY) exhibited the highest CO generation rate of 18.3 mmol g-1 h-1 and a selectivity of 98.8%. This superior performance is attributed to the synergistic effects of pyrenyl and -C≡C-Ni(PBu3)2-C≡C- moieties. The pyrenyl block functions as an intramolecular π-conjugation channel, facilitating kinetically favorable electron transfer, while the -C≡C-Ni(PBu3)2-C≡C- moiety serves as the catalytic site that enhances CO2 adsorption and activation, thereby suppressing competitive hydrogen evolution. This study provides a new perspective on MGY-based photocatalysts for developing highly active and low-cost catalysts for CO2 reduction.

Photoirradiation-enhanced behavior via morphological manipulation of CoFe2O4/g-C3N4 heterojunction for supercapacitor and CO2 reduction

Regulating the morphology of graphitic carbon nitride (g-C3N4, CN) and constructing CoFe2O4/g-C3N4 (CFO/CN) heterojunctions were adopted in the photocatalytic energy storage and photocatalytic CO2 reduction (PCR). CFO/CNS had outstanding light response ability, while CFO/CNT possessed excellent charge transfer ability. Consequently, CFO/CNT electrode exhibited the highest specific capacitance without light, CFO/CNS electrode showed the most obvious photo-enhanced capacitance behavior with an increase by 21.05 % under light. This was ascribed to the generation and separation of photo-generated carriers, promoting oxidation/reduction reactions. And in PCR, the electron consumption rates of four CFO/CN heterojunctions were CFO/CNT > CFO/BCN > CFO/MCN > CFO/CNS. CFO/CNT presented the highest photocatalytic activity, attributing to the strong redox ability and photo-enhanced electron transfer. This strategy of utilizing CFO/CN heterojunctions to construct photo-enhanced supercapacitor electrodes and photocatalytic CO2 reduction catalysts provided new ideas for energy conversion and storage.

Engineering intricacies of implementing single-atom alloy catalysts for low-temperature electrocatalytic CO2 reduction

Engineering intricacies of implementing single-atom alloy catalysts for low-temperature electrocatalytic CO2 reduction

Enhancing photocatalytic performance of rose-shaped Co/Ni bimetallic organic framework for reducing CO2 to CO under visible light

Co-MOF-74, composed of Co salt as the metal source and 2,5-dihydroxyterephthalic acid as the organic ligand, is widely used as a catalyst for the photocatalytic reduction of CO2 due to its open metal sites, high porosity, large specific surface area, and high CO2 adsorption capacity. However, its effectiveness in CO2 conversion is limited by weak electron transfer capabilities and a high rate of electron/hole pair recombination. To address these limitations, a bimetallic strategy was employed to significantly improve the catalytic performance of Co-MOF-74 for photocatalytic CO2 reduction. Stable bimetallic Co/Ni-MOF-74-x (x = 1, 2, 3) with controllable morphology and metal ratios were synthesized by adjusting the molar ratios of Co2+ and Ni2+ and combining them with 2,5-dihydroxyterephthalic acid. The introduction of Ni2+ led to a significant increase in the specific surface area, from 204.999 m2/g (Co/Ni-MOF-74) to 790.873 m2/g (Co/Ni-MOF-74-1). In addition, the band gap of bimetallic Co/Ni-MOF-74-1 was narrowed to 1.4 eV, which enhanced charge transfer. As a result, photocatalytic experiments demonstrated that the CO2 conversion efficiency of bimetallic Co/Ni-MOF-74-1 was significantly improved, reaching 4.539 mmol/g/h, compared to that of the monometallic Co-MOF-74. Finally, a synergistic photocatalytic mechanism involving ligand activation was proposed to explain the reaction process of the bimetallic Co/Ni-MOF-74 catalyst. Meanwhile, this study highlights that the bimetallic strategy is an effective approach to optimizing the performance of MOF catalysts for the photocatalytic reduction of CO2.

Transition metal-loaded C2N catalysts for selective CO2 reduction to CH4: Insights from first-principles calculations

The escalating atmospheric CO2 levels due to fossil fuel consumption pose significant environmental challenges, including the greenhouse effect and ocean acidification. Converting CO2 into valuable fuels and chemicals through electrochemical CO2RR is a promising strategy to mitigate these issues. However, the high thermodynamic stability of CO2 and the competing HER present challenges in achieving high selectivity and efficiency. This study employs first-principles calculations to investigate the performance of transition metal trimer catalysts (3TM-C2N, TM = Mn, Mo, Ru, Ti) supported on porous graphitic C2N for CO2RR to CH4. The catalysts were constructed and their stability, electronic structure, and CO2 adsorption mechanisms were systematically analyzed using DFT. The results indicate that 3TM-C2N catalysts are structurally stable, efficiently adsorb and activate CO2, and effectively suppress HER. Notably, 3Mn-C2N demonstrated optimal selectivity for CH3OH and CH4 with a limiting potential of −0.44 V, while 3Ru-C2N showed superior selectivity for the same products at limiting potentials of −0.86 V and −0.73 V, respectively. These findings provide theoretical insights for the experimental optimization of C2N-based catalysts and guide the development of efficient CO2RR electrocatalysts.

Development of Ce-doped NH2-UiO-66(Zr) photocatalysts for efficient CO2 reduction in an aqueous system

A series of bimetallic NH2-UiO-66(Zr/Ce) catalysts with varying Zr/Ce molar ratios were synthesized using a straightforward solvothermal method. Among the tested samples, NH2-UiO-66(Zr/Ce1:1) demonstrated superior performance, attributed to its optimized electronic structure, enhanced CO2 adsorption capacity, and efficient separation of photogenerated electron-hole pairs, outperforming the NH2-UiO-66(Zr) variant. The NH2-UiO-66(Zr/Ce1:1) exhibited a bandgap of 2.67 eV, CO2 adsorption capacity of 65.85 cm3/g, and a photocurrent density of 0.43 μA·cm−2. This catalyst achieved achieving a CO production rate of 30.04 μmol·g−1·h−1, representing a 1.66-fold improvement over NH2-UiO-66(Zr), with CO selectivity increasing from 95.2 % to 97.2 %. The results underscore the efficacy of Zr/Ce bimetallic NH2-UiO-66 for CO2 reduction, highlighting the potential of structural modifications in NH2-UiO-66 to enhance photocatalytic performance. This study provides valuable insights into the design and development of advanced catalysts for efficient and sustainable CO2 reduction.

In situ constructing 2D/2D layered BiOBr/Bi2O2CO3 heterostructure for efficient photocatalytic reduction CO2 to CO

Photocatalytic reduction of CO2 to valuable energy materials is necessary for sustainable development. It is a considerable challenge to prepare photocatalysts for CO2 photoreduction with excellent separation capability of carriers by simple way. Herein, the BiOBr/Bi2O2CO3 type-II heterostructure was constructed by in situ conversion at room temperature. Combining the advantages of the 2D/2D layered structure can form a close contact interface and the type-II heterostructure can facilitate the transport of photogenerated charges, the BiOBr/Bi2O2CO3 composite showed significant enhancement in photocatalytic CO2 reduction performance. The most obvious performance enhancement was observed for 2.0-BiOBr/Bi2O2CO3, where CO yield could reach 29.55 μmol·g−1 for 3 h under light irradiation, it is 11 and 4 times higher than Bi2O2CO3 and BiOBr, respectively. And the sample exhibits excellent cycling stability in photocatalytic tests. In situ Fourier Transform Infrared spectroscopy confirmed that the important intermediates of the reaction are *COOH and *CO. The photocatalytic reduction mechanism of CO2 to CO in the BiOBr/Bi2O2CO3 type-II heterostructure was further analyzed. This study provides feasible solutions for selecting photocatalytic materials and designing facile preparation of efficient 2D/2D catalysts for photocatalytic reduction of CO2.