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• CoPc/Bi 2 WO 6 heterojunction with Co2+ centres have been effectively fabricated. • The built-in electric field and covalent bonding cause effective Z-scheme system. • The Co2+ centres could capture photoelectrons and encourage the CO 2 activation. • Optimized CoPc/Bi 2 WO 6 heterojunction shows superior photocatalytic activities for CO 2 reduction. The Z-scheme heterojunction offers hope for CO 2 reduction due to its unique charge migration, superior separation, and high redox capacity. Yet, regulating charge transfer in nanoscale heterostructure interfaces remains a significant challenge. Herein, we systematically engineered interfacial dual tungsten (W) bonds and built-in electric field (BIEF) modulated Z-scheme heterostructure composed by CoPc and Bi 2 WO 6 (BWO), stimulate a Z-scheme charge shuttle cascade, channelling electrons from BWO to CoPc, thereby optimizing charge separation and upholding a high redox potential. The optimized photocatalyst exhibits high CH 4 /CO 2 rate of ∼2.5 compared to pure BWO under vis-light for efficient CO 2 reduction. The improved photoactivity is confirmed through theoretical/experimental evidence, highlighting the significance of newly formed W-O-C and W-Co bonds and BIEF. These components function as atomic-level interfacial channels, efficiently accelerating Z-scheme interfacial electron shuttle and shortening the electron-shuttle distance. Furthermore, the extended visible-light range, enabled by the molecular dispersion of CoPc, and the favourable catalytic function of its central metal cation (Co2+) for CO 2 activation, significantly contribute to the overall enhancement. This work offers a new platform to design emerging modulated CO 2 photoreduction systems based on Z-scheme charge shuttle by regulating atomic-level interface and BIEF to remarkably encourage photocatalytic CO 2 photo-reduction performance. [ABSTRACT FROM AUTHOR]

A S-scheme heterojunction of CuPc/DR-MoS 2 with abundant sulfur vacancies is proposed, enabling extended visible-light absorption, enhanced charge carrier separation/transfer, and improved efficiency of semiconductors. Additionally, sulfur vacancies play a significant role in enhancing CO 2 adsorption/activation on the photocatalyst surface during photocatalysis. [Display omitted] Constructing a heterojunction by combining two semiconductors with similar band structures is a successful approach to obtaining photocatalysts with high efficiency. Herein, a CuPc/DR-MoS 2 heterojunction involving copper phthalocyanine (CuPc) and molybdenum disulfide with S-rich vacancies (13.66%) is successfully prepared by the facile hydrothermal method. Experimental results and theoretical calculations firmly demonstrated that photoelectrons exhibit an S-scheme charge transfer mechanism in the CuPc/DR-MoS 2 heterojunction. The S-scheme heterojunction system has proven significant advantages in promoting the charge separation and transfer of photogenerated carriers, enhancing visible-light responsiveness, and achieving robust photoredox capability. As a result, the optimized 3CuPc/DR-MoS 2 S-scheme heterojunction exhibits photocatalytic yields of CO and CH 4 at 200 and 111.6 μmol g-1h−1, respectively. These values are four times and 4.5 times greater than the photocatalytic yields of pure DR-MoS 2. This study offers novel perspectives on the advancement of innovative and highly effective heterojunction photocatalysts. [ABSTRACT FROM AUTHOR]

Van der Waals (vdW) heterojunctions enhance photocatalyst efficiency but face electron transfer challenges at component interfaces due to large spacing and potential barriers. We introduce a novel wet chemistry approach to enhance the efficiency of photocatalysts by creating a functionalized graphene-modulated Z-scheme vdW heterojunction (xZnPc/yG-WO 3) to eliminate interfacial potential differences, enabling better electron transfer for improved photocatalytic reactions and molecular dispersion. [Display omitted] The construction of van der Waals (vdW) heterojunctions is a key approach for efficient and stable photocatalysts, attracting marvellous attention due to their capacity to enhance interfacial charge separation/transfer and offer reactive sites. However, when a vdW heterojunction is made through an ex-situ assembly, electron transmission faces notable obstacles at the components interface due to the substantial spacing and potential barrier. Herein, we present a novel strategy to address this challenge via wet chemistry by synthesizing a functionalized graphene-modulated Z-scheme vdW heterojunction of zinc phthalocyanine/tungsten trioxide (xZnPc/yG-WO 3). The functionalized G-modulation forms an electron "bridge" across the ZnPc/WO 3 interface to improve electron transfer, get rid of barriers, and ultimately facilitating the optimal transfer of excited photoelectrons from WO 3 to ZnPc. The Zn2+ in ZnPc picks up these excited photoelectrons, turning CO 2 into CO/CH 4 (42/22 μmol.g−1.h−1) to deliver 17-times better efficiency than pure WO 3. Therefore, the introduction of a molecular "bridge" as a means to establish an electron transfer conduit represents an innovative approach to fabricate efficient photocatalysts designed for the conversion of CO 2 into valued yields. [ABSTRACT FROM AUTHOR]

[Display omitted] • 2D/2D Van der Waals (VDW) heterojunction between BCN/CuPc. • Phosphate group insertion between copper phthalocyanine (CuPc) and B-doped and N -deficient g-C 3 N 4 (BDCNN) to design and construct a Van der Waals heterojunction. • Phosphate group as a charge modulator and an efficient conduit for charge transfer. • Interfacial interaction charge transfer mechanism. The realization of 2D/2D Van der Waals (VDW) heterojunctions represents an advanced approach to achieving superior photocatalytic efficiency. However, electron transfer through Van der Waals heterojunctions formed via ex-situ assembly encounters significant challenges at the interface due to contrasting morphologies and potential barriers among the nanocomposite substituents. Herein, a novel approach is presented, involving the insertion of a phosphate group between copper phthalocyanine (CuPc) and B-doped and N -deficient g-C 3 N 4 (BDCNN), to design and construct a Van der Waals heterojunction labeled as xCu[acs]/yP-BDCNN. The introduction of phosphate as a charge modulator and efficient conduit for charge transfer within the heterojunction resulted in the elimination of spatial barriers and induced electron movement from BDCNN to CuPc in the excited states. Consequently, the catalytic central Cu2+ in CuPc captured the photoelectrons, leading to the conversion of CO 2 to C 2 H 4 , CO and CH 4. Remarkably, this approach resulted in a 78-fold enhancement in photocatalytic efficiency compared to pure BDCNN. Moreover the findings confirm that the 2D-2D 4Cu[acs]/9P-BDCNN sheet-like heterojunction effectively boosts photocatalytic activity for persistent pollutants such as methyl orange (MO), methylene blue (MB), rhodamine B (RhB), and tetracycline antibiotics (TCs). The introduction of "interfacial interacting" substances to establish an electron transfer pathway presents a novel and effective strategy for designing photocatalysts capable of efficiently reducing CO 2 into valuable products. [ABSTRACT FROM AUTHOR]