Yingpu Bi

NiFe-based catalysts are highly active for the oxygen evolution reaction, but their precise fabrication on photoanodes at subnanometer scale for accelerating charge transport and maximizing active sites remains a challenge. Herein, we report a facile approach to deposit trimesic acid (TA) coordinated subnanometer Ni@Fe hydroxides (Ni-TA-Fe) on nanoporous WO3 photoanodes. This WO3/Ni-TA-Fe photoanode exhibited a record photocurrent density of ∼2.4 mA cm–2 at 1.23 VRHE under AM 1.5 G irradiation (100 mW cm–2) with an enhanced stability, which is much higher than that of pristine WO3 photoanodes. Comparative experiments, characterizations, and density functional theory calculations revealed that the subnanometer Ni catalyst layers could effectively inhibit the dissolution of W atoms from the surface lattice and promote the structural stability of the WO3 photoanode during PEC water oxidation. Furthermore, the strong coordination and electron-trapping capability of TA could efficiently promote charge redistribution in Fe catalyst layers, resulting in the activation and transformation of surface Fe sites into high-valence Fe4+ species for significantly improving the OER activity. This work provides the viable pathway to active and durable bimetallic catalysts to achieve high-performance and stable PEC water splitting.

Plasmonic catalysis offers a promising route to solar-driven chemical transformations, yet its efficiency is severely limited by the high energy barrier for hot electron utilization, particularly for activating inert bonds. While recent progress suggests that the plasmonic local electric field can synergize with hot carriers to enhance reactivity, the specific contribution of the local electric field to bond activation remains unclear. Herein, we observed the visible-light-driven cleavage of the C–F bond under the intense local electric field of the Ag interparticle gaps via in situ surface-enhanced Raman spectroscopy (SERS). The relationship between nanoparticle size-dependent local electric field enhancement/hot carrier generation efficiency and C–F bond cleavage kinetics demonstrates that the local electric field can effectively lower the energy barrier for hot electron injection into adsorbate’s lowest unoccupied molecular orbital (LUMO). Density functional theory (DFT) calculations further suggest that the contribution of the local electric field (CF) to the barrier reduction is at least 25% under our experimental conditions by lowering the adsorbate LUMO level. These insights deepen the mechanistic understanding of plasmonic catalysis, such as the superlinear dependence of the reaction rate on light intensity, presenting the local electric field as a critical design parameter for high-efficiency plasmonic catalysts targeting inert chemical bond activation.

Defect engineering is a promising strategy in heterogeneous catalysis, while understanding how the defective sites affect reactivity still remains ambiguous. Herein, we demonstrated an in‐depth experimental study of dynamic interaction of CO ₂ molecules on defective In ₂ S ₃ surfaces by integrating operando X‐ray photoelectron spectroscopy with infrared spectroscopy. More specifically, the formation of S vacancy could promote the electron enrichment on adjacent In sites for facilitating CO ₂ molecule adsorption, accompanying with the emergence of high oxidation states of surface In sites. Upon light illumination, the adsorbed CO ₂ molecules undergo a sequential transformation into *COOH and *CO intermediates. However, an unexpected upside‐down inversion of *CO species on defective In sites from In–*CO to In–*OC has been firstly observed, severely restraining desorption of CO product from In ₂ S ₃ surfaces. Further tailoring the electronic structure of defective In sites by substituting residual S atom with O atom for inhibiting *CO inversion, a significant improvement of CO evolution activity has been achieved (18.3 µmol g ⁻¹ h ⁻¹ ), nearly five times higher than that of pristine In ₂ S ₃ (3.77 µmol g ⁻¹ h ⁻¹ ). This work provides the new insights on dynamic roles of defect‐derived active sites in determining catalytic activity, which might offer opportunities for fine control of catalytic process.

Photothermal catalytic dry reforming of methane (DRM) is a promising process for converting two greenhouse gases into syngas. However, it still suffers from poor reactivity and coke-induced instability. Here, we report a Rh-embedded SrTiO₃ with stable interfacial sites (Rh^δ+-O_v-Ti) induced by strong electronic metal-support interactions, which enables highly efficient and stable DRM. In situ characterizations and theoretical calculations confirm that these interfacial sites act as intrinsic active centers for the adsorption and activation of CH₄ and CO₂ molecules via the CH₃O* pathway, without coking. Furthermore, the local charge redistribution and oxygen vacancy (O_v) regeneration enable the dynamic evolution of the Rh^δ+-O_v-Ti interfacial sites during DRM. Consequently, a syngas yield of 7.6/9.6 mol g_Rh^-1 h^-1 for H₂/CO production and durability of 100 h were achieved with the Rh/SrTiO₃ catalyst under light irradiation. More importantly, this embedding strategy can be universally applied to synthesize other anticoking catalysts for photothermal DRM and other structure-sensitive reactions.

Understanding of surface defects of a catalyst during the reaction process is critical to establish an accurate structure‐activity relationship. Herein, combining operando X‐ray diffraction/photoelectron spectroscopy with scanning probe microscope, we have first established the correlations between CO ₂ photoreduction activities and crystal‐structure/active‐site of defective ZnAl layered double hydroxides (ZnAl‐LDH). Specifically, the introduction of oxygen vacancies in ZnAl‐LDH could effectively promote the selective adsorption of both CO ₂ and H ₂ O molecules on surface Al and Zn active sites, respectively, leading to opposite transition states and the evident shrinking of crystalline structures. Under light irradiation, the adsorbed CO ₂ molecules transformed into *COOH intermediate on surface Al active sites, while the H ₂ O molecules dissociated into OH group on Zn sites to provide proton, simultaneously leading to the expansion of crystalline structures and increase of layer spacing. Accordingly, these defect‐dependent evolutions of surface active sites and crystalline structure contributed to the significant improvement of CO ₂ reduction to CO activity (17.2 µmol g ⁻¹ h ⁻¹ ), much higher than that of pristine ZnAl‐LDH (6.3 µmol g ⁻¹ h ⁻¹ ). This work provides new insights for in‐depth understanding of the electronic and crystalline changes of defective photocatalysts during the reaction process.

Understanding of surface defects of a catalyst during the reaction process is critical to establish an accurate structure‐activity relationship. Herein, combining operando X‐ray diffraction/photoelectron spectroscopy with scanning probe microscope, we have first established the correlations between CO ₂ photoreduction activities and crystal‐structure/active‐site of defective ZnAl layered double hydroxides (ZnAl‐LDH). Specifically, the introduction of oxygen vacancies in ZnAl‐LDH could effectively promote the selective adsorption of both CO ₂ and H ₂ O molecules on surface Al and Zn active sites, respectively, leading to opposite transition states and the evident shrinking of crystalline structures. Under light irradiation, the adsorbed CO ₂ molecules transformed into *COOH intermediate on surface Al active sites, while the H ₂ O molecules dissociated into OH group on Zn sites to provide proton, simultaneously leading to the expansion of crystalline structures and increase of layer spacing. Accordingly, these defect‐dependent evolutions of surface active sites and crystalline structure contributed to the significant improvement of CO ₂ reduction to CO activity (17.2 µmol g ⁻¹ h ⁻¹ ), much higher than that of pristine ZnAl‐LDH (6.3 µmol g ⁻¹ h ⁻¹ ). This work provides new insights for in‐depth understanding of the electronic and crystalline changes of defective photocatalysts during the reaction process.

Artificial carbon fixation is a promising pathway for achieving the carbon cycle and environment remediation. However, the sluggish kinetics of oxygen evolution reaction (OER) and poor selectivity of CO₂ reduction seriously limited the overall conversion efficiencies of solar energy to chemical fuels. Herein, we demonstrated a facile and feasible strategy to rationally regulate the coordination environment and electronic structure of surface-active sites on both photoanode and cathode. More specifically, the defect engineering has been employed to reduce the coordination number of ultrathin FeNi catalysts decorated on BiVO₄ photoanodes, resulting in one of the highest OER activities of 6.51 mA cm⁻² (1.23 V _RHE, AM 1.5G). Additionally, single-atom cobalt (II) phthalocyanine anchoring on the N-rich carbon substrates to increase Co–N coordination number remarkably promotes CO₂ adsorption and activation for high selective CO production. Their integration achieved a record activity of 109.4 μmol cm⁻² h⁻¹ for CO production with a faradaic efficiency of > 90%, and an outstanding solar conversion efficiency of 5.41% has been achieved by further integrating a photovoltaic utilizing the sunlight (> 500 nm).

A facile strategy has been reported for anchoring Co single atoms on BiOCl nanosheets to enable efficient CO₂ photoreduction, and the neighboring effect of single-atom cobalt has been clarified by in situ X-ray photoelectron spectroscopy.

We demonstrated a facile electrochemical treatment for in situ anchoring of Cu ₄ clusters in a graphitic C ₃ N ₅ framework, leading to remarkable improvements of photocatalytic reactivity and selectivity towards CO ₂ reduction to ethanol.

A facile and feasible strategy for forming strong interfacial bonding between FeOOH catalysts and Fe ₂ O ₃ photoanodes through an oxygen vacancy self-healing process, which exhibited a remarkable improvement in PEC water oxidation activity.