Counter Electrode Catalyst Research Articles

Fabrication of CoM (M= Ni, Cu) alloys modified carbon electrocatalysts by pyrolysis of dual-metal-site metal-organic frameworks for efficient dye-sensitized solar cells

The regulation of interface properties of multi-component transition metals in carbon-based catalyst has been an effective method to boost the electrochemical performance of counter electrode (CE) catalysts for dye-sensitized solar cells (DSSCs). Herein, CoNi-metal-organic framework (MOF) and CoCu-MOF are fabricated through introducing Ni and Cu into the stable Co-MOF, and used as sacrificial precursor in the followed pyrolysis-alloying process. And then, the target product CoM (M=Ni, Cu)/N-doped polyhedron-like carbon (NC) are successfully obtained, in which CoNi and CoCu alloy nanoparticles are uniformly dispersed on the N-doped carbon skeleton. Such MOFs-derived carbon matrix can not only supply as conductive network, but also isolate the alloy nanoparticles to avoid agglomeration, ensuring more effective active sites. Meanwhile, the built-in electric field generated by the Mott-Schottky interface effect of CoM/NCs could regulate the electronic structure inside the catalysts, resulting in faster electron transfer ability. Significantly, the reduced work function due to the introduction of Cu atoms leads to stronger self-driven electron transfer at the heterogeneous interface of CoCu/NC, which helps to improve reaction activity and electrocatalytic efficiency. Among the tested catalysts, CoCu/NC displays a more satisfying power conversion efficiency (PCE) of 7.60 % when assembled into CE of DSSC, also superior to 7.19 % of Pt.

Nitrogen-doped mesoporous carbon combined with carbon nanotubes as counter electrode catalysts for quantum dot sensitized solar cells with record efficiency

The fabrication of a counter electrode possessing elevated catalytic efficiency and steadfast stability is a crucial prerequisite for the high-performance quantum dot sensitized solar cells (QDSCs). Mesoporous carbon (MC) has been adopted as the desired CE material in the past years, but the disadvantage of its poor conductivity has limited further development of the performance of QDSCs. In this study, we present a straightforward approach for producing highly effective counter electrodes through the integration of nitrogen-doped mesoporous carbon (N-MC) with carbon nanotubes (CNTs), forming a composite material that is deposited onto a titanium mesh substrate. The counter electrode (CE) based on composite materials shows excellent electrocatalytic performance, synergistically benefiting from large specific areas of N-MC and high conductivity of CNTs. Electrochemical measurements reveal that the optimal CEs exhibit excellent catalytic reduction activity as well as high electron mobility. Consequently, the corresponding QDSCs show a record power conversion efficiency of 16.68 %.

Design and construction of MoS2/Ni3S2 nanosheets decorated on multi-walled carbon nanotubes as a sustainable counter electrode for dye-sensitized solar cells: An experimental and computational investigation

To achieve a satisfactory photovoltaic performance in dye-sensitized solar cells (DSSCs), counter electrode (CE) catalysts with low cost, superior catalytic activity and excellent conductivity should be developed. Herein, we successfully prepared the MoS2/Ni3S2 heterostructures via the hydrothermal method and decorated on multi-walled carbon nanotubes (MWCNTs) by sonication method. The performance of the prepared CEs was investigated by various electrochemical techniques. Based on the electrochemical tests, the MoS2/Ni3S2/MWCNTs ternary nanocomposite displayed high electron transfer ability, remarkable catalytic activities, and good stability in the I3−/I− electrolyte. The power conversion efficiency (PCE) of DSSCs based on MoS2/Ni3S2/MWCNTs CE reached 8.27 %, which was even higher than that of the DSSC with Pt CE (7.23 %). The excellent performance of the catalyst is related to the structural properties, synergistic effect of MoS2/Ni3S2 and MWCNTs, and high porosity of MoS2/Ni3S2/MWCNTs composite. The results of calculations indicated that by decorating the MoS2/Ni3S2 on carbon nanotubes (CNTs), the bandgap decreased to 2.79 eV, which was smaller than the individual CNTs (6.27 eV). This finding depicted that synergistic effect between MoS2/Ni3S2 and MWCNTs can reduce the bandgap of MoS2/Ni3S2/MWCNTs composite. The lower bandgap mostly results in higher electrical conductivity and lower charge-transfer resistance, which plays an important role in improving the efficiency of DSSCs.

Graphene-Supported Small-Sized FeSe2 Nanoparticles As Efficient Counter Electrode Catalysts for Dye-Sensitized Solar Cells

Graphene-Supported Small-Sized FeSe₂ Nanoparticles As Efficient Counter Electrode Catalysts for Dye-Sensitized Solar Cells

Construction of magnetic Fe2P2O7/Ni2P@Mxene composite counter electrode for efficient dye-sensitized solar cells

Exploring an effective synthesis method for preparing platinum (Pt)-free counter electrode (CE) catalysts with low-cost, superior catalytic ability and electrochemical stability is essential for dye-sensitized solar cells (DSSCs). In this work, the synthesis of Fe2P2O7/Ni2P was realized through hydrothermal treatment of Fe2P2O7/Ni2P precursor and followed phosphorization process. Next, the Fe2P2O7/Ni2P@Mxene composite was prepared by physical grinding with different contents of Ti3C2 Mxene. The Fe2P2O7/Ni2P@Mxene CE exhibits the most excellent catalytic reduction ability and the fine charge-transfer resistance of 1.0 Ω cm2 for the reduction of triiodide electrolyte with 80 wt% Ti3C2 Mxene, which has surpassed the Pt CE. As consequence, the photoelectric conversion efficiency of 9.29 % is achieved for the DSSC with the Fe2P2O7/Ni2P@Mxene CE under the optimized conditions, which is much higher than that of the DSSC Pt-based (7 %). Its high conductivity, prefect catalytic activity, and their synergistic effects of Fe2P2O7/Ni2P and Ti3C2 Mxene towards iodide/triiodide electrolyte of the Fe2P2O7/Ni2P@Mxene CE play an important role in the generation of high efficiency for the cells.

NiSe2-CoSe2 hollow polyhedron as counter electrode catalyst for high-efficiency dye-sensitized solar cells

The design of efficient counter electrode (CE) materials for dye sensitized solar cells (DSSCs) strongly depend on the microstructure construction and the effective combination of different active components. In this study, a hollow polyhedral structured NiSe2-CoSe2 composite electrode was synthesized through the direct selenization of the hollow nanocage morphology nickel-cobalt layered double hydroxide (NiCo-LDH) ultrathin nanosheets, which was derived from ZIF-67 nanocrystals. Notably, owing to the unique hollow structure and synergistic effect of the Ni-Co bimetallic selenides, the hollow polyhedral NiSe2-CoSe2 CE exhibited the expected electrochemical catalytic activity in the reduction of triiodide, as revealed by electrochemical impedance spectroscopy, cyclic voltammetry and Tafel polarization measurements. The photovoltaic results revealed that the PCE of the NiSe2-CoSe2 CE reached 8.21 %, which was higher than those of the Pt and CoSe2 CEs (7.62 % and 6.78 %, respectively). Moreover, the hollow NiSe2-CoSe2 CE exhibited a favourable photocurrent response upon light on-and-off cycling and improved stability over multiple start. This study provides a meaningful reference for the construction of hollow polymetallic transition-metal selenides for DSSC devices.

Phosphorus-doped molybdenum disulfide as counter electrode catalyst for efficient bifacial dye-sensitized solar cells

MoS2 is a promising counter electrode material for dye-sensitized solar cell owing to its optical and electrical properties and two-dimensional layered structure. However, it still suffers from minimal conductivity, poor charge transport and less active sites. The present study offers a promising method for enhancing catalytic and fast charge transfer in MoS2 through heteroatom doping of phosphorus. A facile one-step hydrothermal treatment was acquired to do the phosphorus doping. The spin-coated P-doped MoS2 (MSP2) counter electrode (CE) shows a superior power conversion efficiency of 7.93% for front illumination and 5.34% for rear illumination, outperforming Pt-based (7.41% and 5.75%) CE. Thus, phosphorous incorporation increases the number of active sites and improves the catalytic property of the material. The P-doped MoS2 (MSP2) CE film also shows high transmittance, making it a suitable choice for bifacial type of solar cell.

Colloid synthesis of Ni12P5/N, S-doped graphene as efficient bifunctional catalyst for alkaline hydrogen evolution and triiodide reduction reaction

Designing high-efficient bifunction catalysts with excellent catalytic activity and enhanced charge-transfer capability in both alkaline hydrogen evolution reaction (HER) and triiodide reduction reaction (IRR) is of utmost significance to advance the development of green hydrogen production and photovoltaics, respectively, yet remains a crucial challenge. Here, highly dispersed and small-sized Ni12P5 nanocrystals with narrow size distribution was well attached on the surface of N, S co-doped graphene (Ni12P5/NSG) by the facile hot-injection method. As expected, the optimized Ni12P5/NSG requires a relatively low overpotential of 132.94 ± 0.08 mV to deliver a current density of 10 mA cm−2 in alkaline condition, accompanied with remarkable long-time durability with negligible attenuation over 50 h. Density functional theory (DFT) calculations revealed that the positively synergic effect between Ni12P5 and NSG are in favor of modulating the rate determining step of the dissociation of H2O to *(OH-H), thereby upgrading its HER activity. When used as the counter electrode catalyst for IRR in DSSCs, the resultant Ni12P5/NSG exhibits extraordinary Pt-like catalytic activity and well electrochemical stability in iodide-based electrolyte, delivering a high photoelectric conversion performance (PCE) comparable to Pt. The improved PCE can be attributed to the accelerated interfacial charge-transfer capability around active sites for facilitating the reaction kinetics of IRR, as demonstrated by DFT calculations. This work provides an effective strategy for synthesizing cost-effective composites with multi-active sites and offering valuable insight into the structure-performance relationship, which is conducive to guide the synthesis of promising catalysts in the energy conversion field.

A hierarchical strategy for fabricating synergistic 3D network bio-based porous carbon and 0D niobium-based bimetallic oxides as counter electrodes for I- and Cu-mediated dye-sensitized solar cells with N719 and Y123 dyes

Designing cost-effective counter electrode (CE) catalysts with advanced nanostructures and exploring their application in different dye-electrolyte systems is crucial for the development of dye-sensitized solar cells (DSSCs). In this work, two types of 3D network bio-based porous carbon (3D-BPC) loaded 0D niobium-based bimetallic oxide nanohybrids (CoNb2O6/3D-BPC and NiNb2O6/3D-BPC) were synthesized using a hierarchical strategy. Benefiting from the optimization of the electron transport pathways and enrichment of catalytically active sites via the hierarchical 0D/3D structure, formed by 3D-BPC and MNb2O6 (M = Co, Ni), the catalytic reduction ability of MNb2O6/3D-BPC was significantly enhanced. To explore the photovoltaic performance of the MNb2O6/3D-BPC based DSSC, the I3−/I− electrolyte and N719 dye system and the Cu2+/Cu+ electrolyte and Y123 dye system were simultaneously employed. The solar cells assembled with the CoNb2O6/3D-BPC and NiNb2O6/3D-BPC CE exhibited device efficiencies of 7.03% and 7.14% in the N719-I3−/I− system, respectively, and 1.84% and 2.42% in the Y123-Cu2+/Cu+ system, respectively, which were almost equal to those of Pt under the same system. Additionally, MNb2O6/3D-BPC catalysts exhibited promising stability in I3−/I− electrolyte. This work provides guidance for the construction of low-cost and high-efficiency nanohybrid catalysts for new energy conversion devices.

Phase-Selective Synthesis of Cobalt Sulfide Heterostructure Catalysts as Efficient Counter electrodes in Dye-Sensitized Solar Cells.

Developing a cost-saving, high-efficiency, and simple synthesis of counter electrode (CE) material to replace pricy Pt for dye-sensitized solar cells (DSSCs) has become a research hotspot. Owing to the electronic coupling effects between various components, semiconductor heterostructures can significantly enhance the catalytic performance and endurance of counter electrodes. However, the strategy to controllably synthesize the same element in several phase heterostructures used as the CE in DSSCs is still absent. Here, we fabricate well-defined CoS2/CoS heterostructures and use them as CE catalysts in DSSCs. The as-designed CoS2/CoS heterostructures display high catalytic performance and endurance for the triiodide reduction in DSSCs thanks to the combined and synergistic effects. As a result, a DSSC with CoS2/CoS achieves a high power conversion efficiency of 9.47% under illumination, surpassing that of pristine Pt-based CE (9.20%). Besides, the CoS2/CoS heterostructures possess a quick activity initiation process and extended stability, broadening their potential applications in various areas. Therefore, our proposed synthetic approach could offer new insights for synthesizing functional heterostructure materials with improved catalytic activities in DSSCs.

Morphology-dependent catalysis on nanostructures Fe2O3@MWCNT as Pt-free counter electrode for dye-sensitized solar cells

The doped transition metal oxides (TMOs) substitute for the traditional Pt as the counter electrode (CE) catalyst is a unique way to reduce the cost and improve the power conversion efficiency (PCE) of dye-sensitized solar cells (DSSCs). Herein, four different morphologies and size of Fe2O3 (nanodiscus (ND), nanocubes (NC), nanorings (NR), nanoball (NB)) assisted by multi-walled carbon nanotube (MWCNT) to prepare Fe2O3@MWCNT composites, and then were further utilized in the encapsulated DSSCs. The obtained different morphologies Fe2O3@MWCNT composites had been characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and N2 adsorption-desorption. The significant effects of different morphologies of Fe2O3 on the electrochemical activity of Fe2O3@MWCNT composites as CEs were confirmed by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and Tafel polarization experiments. The DSSCs using Fe2O3@MWCNT composites CEs achieved high PCEs of 6.34 (ND), 6.53(NC), 6.65(NR), and 7.09% (NB) to regenerate traditional I3−/I− shuttles by the photocurrent-photovoltage (J-V) test, respectively, which is due to the synergistic effect between Fe2O3 and MWCNT to improve electrical conductivity and promote a high number of active catalytic sites, implying a remarkable alternative of Pt-free catalyst that can be applied to the encapsulated DSSCs as CEs.

Photovoltaics literature survey (no. 182)

Photovoltaics literature survey (no. 182)

Edge-Active Enriched MoS2 Porous Nanosheets as Efficient Pt-Free Catalysts toward the Triiodide Reduction Reaction

Developing high-efficiency counter electrode (CE) catalysts for the triiodide (I3–) reduction reaction (IRR) is of great significance for the development of cost-effective dye-sensitized solar cells (DSSCs). From the perspective of further enhancing the catalytic activity of CE catalysts by exposing more active sites, edge-active enriched MoS2 porous nanosheets are elaborately constructed using the as-prepared one-dimensional MoO3 rods and poly(vinylpyrrolidone) (PVP) as a template-directing agent and surfactant based on the dissolution–recrystallization strategy (MoS2-P), respectively, while the MoS2 quasi-particles (MoS2-C) and irregular MoS2 aggregations are also synthesized using cetyltrimethyl ammonium bromide (CTAB) as a surfactant and commercial MoO3 powder as a molybdenum source under similar reaction processes. Benefiting from the high specific surface area, exposure of edge active sites, and effective ion diffusion-favored structure, MoS2-P delivers good photovoltaic performance (PCE = 8.16%, Voc = 0.782 V, Jsc = 16.77 mA/cm2, FF = 0.62) when used as a CE catalyst for DSSCs, superior to that of MoS2-C (PCE = 6.87%, Voc = 0.741 V, Jsc = 15.91 mA/cm2, FF = 0.58), which is comparable with that of the Pt-based device (PCE = 8.33%, Voc = 0.775 V, Jsc = 16.85 mA/cm2, FF = 0.64). A series of electrochemical results further reveal that the obtained MoS2-P has good catalytic activity for the IRR and electrochemical stability in iodine-based electrolytes. Hence, our work may provide a promising catalyst for the energy conversion field.

Tungsten Phosphide Microsheets In‐Situ Grown on Carbon Fiber as Counter Electrode Catalyst for Efficient Dye‐Sensitized Solar Cells

AbstractThe development of low‐cost, green, and pollution‐free counter electrode materials with high catalytic activity plays a critical role in improving the photovoltaic performance of dye‐sensitized solar cells (DSSCs). In recent years, transition metal phosphides have been widely used in DSSCs due to their outstanding catalytic activity and stability. Herein, a novel binary phosphide is immobilized on carbon paper (CP) by a two‐step strategy. This strategy involves the preparation of WO3 precursor by the hydrothermal method, and synthesis of tungsten phosphide (WP) with the vapor deposition method, which finally leads to the uniform dispersion of WP on carbon paper. The acquired WP/CP counter electrode demonstrates high electrical conductivity and prefect catalytic ability for reducing triiodide, and the DSSCs assembled with WP/CP counter electrode achieve a high‐power conversion efficiency of 10.29%, which is superior to that of the Pt‐based (7.34%). These findings illustrate that the WP microsheets in‐situ grown on carbon paper are a potential candidate to replace Pt as an economical and efficient counter electrode for DSSCs.

Bimetal Synergetic Strategy of Nickel Iron Selenides to Improve the Catalytic Activity and Cyclic Stability in Dye‐Sensitized Solar Cells

Due to the shortage of freshwater resources and uneven distribution, the dye‐sensitized solar cell has become an effective strategy to obtain green electric energy. However, the counter electrode (CE) is the bottleneck that restricts the development of this technology. Herein, a novel ternary nickel iron selenide with octahedral structure using a simple solvothermal strategy assisted by d‐(+)‐glucose (Ni0.5Fe0.5Se2/C) has been designed and applied as CE catalyst for the first time. Profiting from the synergistic effect between Ni and Fe, the simulative cell with the Ni0.5Fe0.5Se2/C CE yields a superior efficiency of 9.37% to corresponding pure selenides, notably outperforming that of conventional Pt CE (8.79%).

CoP@Ni2P microcrystals in situ grown on carbon fiber as counter electrode catalysts for high-efficiency dye-sensitized solar cells

Transition metal phosphides (TMPs) have recently emerged as outstanding energy conversion and storage materials for their highly active surface sites, electrical conductivity, and thermal and structural stability. However, TMPs as the counter electrode (CE) of dye-sensitized solar cells (DSSC) are rarely reported. Here, cobalt phosphide and nickel phosphide (CoP@Ni2P) microcrystals were successfully prepared in situ grown on carbon fiber of carbon paper (CP) by using simple hydrothermal and phosphating methods, and served as CE in DSSCs. The CP acted as a supporting conductivity substrate and an electron transport “speedway,” which can enhance the electrocatalytic ability of CE and photoelectric conversion efficiency of the devices. The cells based on CoP@Ni2P@CP CE with 1 mmol NiCl2·6H2O deliver a power conversion efficiency of 8.33%, which is superior to that of state-of-the-art Pt-based cell (7.54%). Moreover, the CoP@Ni2P@CP CE also displays a small charge transfer resistance (2.07 Ω cm2) at the interface between electrolyte and CE, as well as prefect electrochemical catalytic stability in I−/I3− electrolyte. These findings indicate that the CoP@Ni2P@CP CE possesses outstanding electrocatalytic and photoelectric conversion performance along with desired stability to be utilized as an efficient Pt-free alternative in DSSCs.

Surface active-site engineering in NiCoSe2/nitrogen-doped carbon dodecahedrons for efficient triiodide reduction in photovoltaics

Constructing Pt-free counter electrode (CE) catalysts with considerable catalytic activity, conductivity, and electrochemical stability are greatly significant for improving the overall power conversion efficiency (PCE) of dye-sensitized solar cells (DSSCs). In this work, we focus on the uniformly distributing Ni and Co elements into layered hydroxide polyhedrons that stemmed from ZIF-67 to transform an active-site enriched composite of NiCoSe2 encapsulated by the derived nitrogen-doped carbon dodecahedrons (NiCoSe2/NC) through the simple pyrolysis procedure. Benefitting from the evenly distributed catalytic sites, unique structure, and positively synergy, the resultant NiCoSe2/NC displays excellent catalytic activity in triiodide reduction reaction (IRR). Consequently, DSSCs fabricated with the optimized NiCoSe2/NC yielded an impressive PCE of 9.92 %, superior to that of the traditional Pt-based devices (8.17 %). The intrinsic mechanism for superior IRR performance of NiCoSe2/NC was mainly ascribed to the favorable adsorption energy (Ead) for capturing I3−, the highly reactive metal catalytic sites at the interface, the efficient electron-transfer pathway, and the enhanced bonding interaction between I 5p and 3d states of the dual metals, as revealed by DFT calculation. It is worthy expecting to provide an extensible pathway for developing a cost-effective composite with profitable structure to guide the synthesis of efficient catalysts in catalytic fields.

Efficient and stable heterostructured Co9S8/Cu7S4 composite counter electrodes derived from Prussian blue analogs for quantum dot-sensitized solar cells

The challenge of boosting the efficiency of QDSSCs lies in the rational development and design of economical, stable and efficient counter electrode (CE) catalysts for fast and efficient electron transport at the CE/electrolyte interface. Here, we creatively construct Co9S8/Cu7S4 heterostructure composite CEs using CuCo-Prussian blue analogs (PBA) as precursor by one-step in-situ solvothermal vulcanization method. Work function analysis and systematic electrochemical characterizations reveal that the presence of heterojunctions in the Co9S8/Cu7S4 can increase the interfacial electric field driving force inside the material, thereby reducing the Rct at CE/electrolyte interface, promoting the efficient transfer of electrons. Correspondingly, the Co9S8/Cu7S4 composite CE can improve the stability and compensate for the deficiency of the single component CE through a decent synergistic catalytic effect. Remarkably, the Mn-CdS/CdSe/ZnS co-sensitized QDSSC equipped with Co9S8/Cu7S4 heterostructure composite CE delivers an optimal conversion efficiency of 8.43% with Jsc = 23.42 mA/cm2, Voc = 0.672 V; FF = 0.54, which was significantly superior to physically mixed CE (PM-Co9S8/Cu7S4, 6.55%), single-component CE (Cu7S4, 5.60%; Co9S8, 5.13%) and conventional Brass/Cu2S CE (4.96%). In briefly, the advanced heterostructure engineering and the abundant, tunable chemical elemental composition of PBA provide new views for the purposeful design of economical and outstanding heterostructured composite CEs.

Boosting catalytic performance of hierarchical Co/Co0.85Se microspheres via Mott-Schottky effect toward triiodide reduction and alkaline hydrogen evolution

Interface engineered composites composing of metal and transition metal selenides have been deemed as promising substitutes as noble Pt in the fields of the energy conversion. Herein, the well-defined hierarchical Co/Co 0.85 Se microsphere with Mott-Schottky (M-S) effect was synthesized by the facile solvothermal method (Co/Co 0.85 Se-3). Interestingly, the as-obtained 3D Co 0.85 Se microsphere was assembled by 2D porous nanosheets. The characteristics including M-S heterojunction and hierarchical structure endows Co/Co 0.85 Se microsphere with high specific surface area, good conductivity, and synergistic effect between metal Co and Co 0.85 Se. More concretely, the optimized Co/Co 0.85 Se exhibits outstanding catalytic activity toward triiodide reduction reaction (IRR). When employed as the counter electrode (CE) catalyst for dye-sensitized solar cell (DSSC), a photoelectric conversion efficiency (PCE) of 8.31 % is achieved, which is 3.36 % higher than that of Pt-control device (8.04 %). Moreover, Co/Co 0.85 Se-3 displays remarkable catalytic activity for hydrogen evolution reaction (HER) with a low overpotential of 107 mV at the current density of 10 mA cm −2 under alkaline condition (1.0 M KOH), accompanying with Tafel slope of 140 mV dec −1 . Our discovery provides an effective approach to develop the cost-effective advanced catalysts to promote the application of DSSC and HER. The hierarchical Co/Co 0.85 Se microspheres with unique Mott-Schottky structure exhibited excellent catalytic performance in the fields of DSSC and HER. • Hierarchical Co/Co 0.85 Se microsphere with M-S effect was synthesized. • Synergy between Co and Co 0.85 Se increases the catalytic activity of Co/Co 0.85 Se-3. • Performance of Co/Co 0.85 Se-3 for DSSC was higher than that of Pt. • Co/Co 0.85 Se-3 exhibited remarkable catalytic property for alkaline HERs.

Design of a specific two–dimensional layered V2C counter electrode for highly effective and stable rigid and flexible quasi–solid–state dye–sensitized solar cells

Exploring Pt–free counter electrode catalysts for quasi–solid–state DSCs (QSDSCs) is significant for overcoming the high cost of Pt counter electrodes and their insufficient contact with the electrolyte. Herein, a two–dimensional (2D) layered MXene, V2C, is synthesized via a simple etching method as a counter electrode in QSDSCs. The impact of the etching time on the catalytic activity toward the regeneration of the I–/I3– redox couple in a quasi–solid–state electrolyte is investigated. After optimization, the V2C etched for 48 h shows a high catalytic activity caused by the constructed unique 2D lamellar structure, which can provide smooth diffusion channels for the penetration of the quasi–solid–state electrolyte to form sufficient contact between the V2C counter electrode and the electrolyte. As a result, the QSDSCs using the 2D layered V2C counter electrode generate a power conversion efficiency (PCE) of 7.48%. Moreover, the catalytic behavior of V2C is further improved by K+ intercalation, and the PCE value of the corresponding QSDSCs is enhanced to 8.30% under standard illumination (1.0 Sun) and to 10.19% under weak illumination (0.1 Sun). Meanwhile, the K+–intercalated V2C shows excellent stability, and 87.9% of the initial PCE of the device is retained after 1050 h in a durability test. This research is expected to provide meaningful support for the exploration of new counter electrode materials and the improvement of the contact between the counter electrode and quasi–solid–state electrolyte for the pursuit of high–performance and low–cost QSDSCs.