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We report the implementation of the ligand‐to‐metal charge transfer (LMCT) in organic semiconductors for improved full visible‐light photocatalysis and understanding of the effects of Pd−N weak coordination of a single‐atomic Pd(II) embedded 2D g‐C3N4 (Pd1/UTCN) homogeneous catalyst analogues on the formation of open metal sites and LMCT induced full‐visible‐light photocatalytic performance. LMCT between Pd(II) and g‐C3N4 allows for wide‐range visible light harvesting and promoting the transport of photogenerated charge of carbon nitride from excitation site to active site. Compared to the porphyrin palladium complex with strong Pd−N coordination, the reversible coordination dissociation of Pd−N of Pd1/UTCN allows for the formation of open active sites photocatalysis, which enables the efficient adsorption, activation, and conversion of substrates. The adsorption of the substrate can promote LMCT between Pd(II) and heptanazine ligands. As a result, Pd1/UTCN exhibited LMCT‐induced efficient full‐visible‐light photocatalytic activity of Suzuki reaction with high selectivity without additional phosphorus ligands. [ABSTRACT FROM AUTHOR]

Photocatalytic H 2 O 2 production has gained significant attention as an environmentally friendly approach. The key is to explore efficient photocatalysts with sufficient active sites and excellent electron transfer capacity. Herein, we propose a novel approach by incorporating carbon dots (CDs) on ethylenediamine capped Zn 0.5 Cd 0.5 S, which was bridged with an interfacial amide bond. Smooth transfer of photoinduced electrons from Zn 0.5 Cd 0.5 S to carbon dots via a high-speed electron channel is afforded by interfacial amide bond. A remarkable H 2 O 2 yield with a rate of 252 μmol/h and an apparent quantum yield (AQY) of 31 % at 400 nm is achieved. Photoelectrochemical analysis and density function theory (DFT) calculation reveal CDs with abundant oxygenous functional groups as active sites, boosting activity and selectivity. This interfacial engineering strategy with the acceleration of electrons transfer and enhanced 2e- selectivity can be applied to advanced photocatalytic systems for the achievement of valuable organics, environmental purification and new energy carriers. [Display omitted] • Carbon dots bridged Zn 0.5 Cd 0.5 S with interfacial amide bond was fabricated. • Amide bond enables smooth electron transfer to O 2 reduction center of carbon dots. • A 34-fold enhancement of H 2 O 2 production was achieved. [ABSTRACT FROM AUTHOR]

We demonstrate a new case of materials–gene engineering to precisely design photocatalysts with the prescribed properties. Based on theoretical calculations, a phase‐doping strategy was proposed to regulate the pathways of CO2 conversion over Au nanoparticles (NPs) loaded TiO2 photocatalysts. As a result, the thermodynamic bottleneck of CO2‐to‐CO conversion is successfully unlocked by the incorporation of stable twinning crystal planes into face‐centered cubic (fcc) phase Au NPs. Compared to bare pristine TiO2, the activity results showed that the loading of regular fcc‐Au NPs raised the CO production by 18‐fold but suppressed the selectivity from 84 % to 75 %, whereas Au NPs with twinning (110) and (100) facets boosted the activity by nearly 40‐fold and established near unity CO selectivity. This enhancement is shown to originate from a beneficial shift in the surface reactive site energetics arising at the twinned stacking fault, whereby both the CO reaction energy and desorption energy were significantly reduced. [ABSTRACT FROM AUTHOR]

We demonstrate a new case of materials–gene engineering to precisely design photocatalysts with the prescribed properties. Based on theoretical calculations, a phase‐doping strategy was proposed to regulate the pathways of CO2 conversion over Au nanoparticles (NPs) loaded TiO2 photocatalysts. As a result, the thermodynamic bottleneck of CO2‐to‐CO conversion is successfully unlocked by the incorporation of stable twinning crystal planes into face‐centered cubic (fcc) phase Au NPs. Compared to bare pristine TiO2, the activity results showed that the loading of regular fcc‐Au NPs raised the CO production by 18‐fold but suppressed the selectivity from 84 % to 75 %, whereas Au NPs with twinning (110) and (100) facets boosted the activity by nearly 40‐fold and established near unity CO selectivity. This enhancement is shown to originate from a beneficial shift in the surface reactive site energetics arising at the twinned stacking fault, whereby both the CO reaction energy and desorption energy were significantly reduced. [ABSTRACT FROM AUTHOR]

Oxygen defects in Hafnium Oxide (HfO2)-based ferroelectric thin films not only are related to the cause of ferroelectricity but also affect the ferroelectric properties of the thin films. This paper, therefore, focuses on the fabrication of Zr:HfO2 thin films by RF (Radio Frequency) magnetron sputtering with Zr-doped HfO2 as the target and examines how oxygen flow impacts the oxygen vacancies and electrical properties thereof. Additionally, TiN thin-film electrodes were prepared by direct current (DC) magnetron reactive sputtering using nitrogen as the reaction gas, the influences of the substrate temperature on the film deposition rate and crystal phase structure were investigated, and the resultant thin-film electrodes with the lowest resistivity were obtained. Furthermore, the ferroelectric hysteresis loop and leakage current density of metal–insulator–metal (MIM) ferroelectric capacitors formed by annealing the 30 nm thick deposited Zr:HfO2 sandwiched between the top and bottom TiN electrodes were measured. The results demonstrate that varying oxygen flow has a considerable effect on oxygen vacancies and the Zr doping concentration of deposited Zr:HfO2 ferroelectric thin films. When the oxygen flow is set to 40 sccm (standard cubic centimeters per minute) and an external electric field strength of 2 mV/cm is applied, the remnant polarization reaches 18 μC/cm2, with a decrease in the leakage current density of 105–6 orders of magnitude. [ABSTRACT FROM AUTHOR]

We demonstrate a new case of materials–gene engineering to precisely design photocatalysts with the prescribed properties. Based on theoretical calculations, a phase‐doping strategy was proposed to regulate the pathways of CO2 conversion over Au nanoparticles (NPs) loaded TiO2 photocatalysts. As a result, the thermodynamic bottleneck of CO2‐to‐CO conversion is successfully unlocked by the incorporation of stable twinning crystal planes into face‐centered cubic (fcc) phase Au NPs. Compared to bare pristine TiO2, the activity results showed that the loading of regular fcc‐Au NPs raised the CO production by 18‐fold but suppressed the selectivity from 84 % to 75 %, whereas Au NPs with twinning (110) and (100) facets boosted the activity by nearly 40‐fold and established near unity CO selectivity. This enhancement is shown to originate from a beneficial shift in the surface reactive site energetics arising at the twinned stacking fault, whereby both the CO reaction energy and desorption energy were significantly reduced. [ABSTRACT FROM AUTHOR]

We develop a new PdCu/UTCN hybrid by loading low-crystalline PdCu NPs on large-area ultrathin 2D carbon nitride (UTCN) nanosheets that exfoliated from bulk g-C 3 N 4 using a twice thermal exfoliation and repolymerization method for photocatalytic Suzuki C-C cross coupling reaction. Due to the advantages of 2D structure of the UTCN and the changes in electronic structure and surface structure of low-crystalline PdCu NPs, PdCu/UTCN shows promoted photocatalytic activity with high selectivity for Suzuki coupling reaction. The TOF value for coupling of iodobenzene with phenylboronic acid is 418.2 h−1, which is 8 and 6.2 times higher than that of previously reported Pd-g-C 3 N 4 and Pd based alloy photocatalysts under the same reaction, respectively. Morevoer, this photocatalyst shows a good functional group tolerance as well as good to excellent yield and selectivity for various substrates. This study reports for the first time the PdCu alloy supported UTCN photocatalytic material for enhanced Suzuki reaction. A new PdCu/UTCN hybrid by loading low-crystalline PdCu NPs on large-area ultrathin 2D carbon nitride (UTCN) nanosheets that exfoliated from bulk g-C 3 N 4 using a twice thermal exfoliation and repolymerization method for photocatalytic Suzuki C-C cross coupling reaction. [Display omitted] • Large-area ultrathin 2D carbon nitride nanosheets (UTCN) is successfully prepared. • PdCu/UTCN hybrid is constructed by loading low-crystalline PdCu NPs on UTCN. • PdCu/UTCN shows excellent photocatalytic activity for Suzuki coupling reaction. • UTCN has a large specific surface area and a higher charge separation efficiency. • Low-crystalline PdCu promotes charge separation, light harvesting, and reaction. [ABSTRACT FROM AUTHOR]

Sunlight-driven valorization of CO 2 into fuels is a promising solution to renewable energy storage, but the design of an integrated and efficient solar-to-chemical conversion system remains challenging. Herein, an all-solar-driven artificial photosynthetic system (APS) by tailoring photovoltaic-photoelectrochemical cell which can efficiently produce formic acid fuel from CO 2 and H 2 O with bias-free illumination is demonstrated. Guided by density functional theory (DFT) calculations, a BiOI–Bi (BOI–Bi) cathode catalyst is synthesized, which is highly selective for CO 2 to HCOOH conversion, and coupled with a single crystalline argon-treated TiO 2 (TiO 2 -Ar) photoanode, whose valence band edge is beneficial for the oxidation of H 2 O to O 2. The APS exhibits high product selectivity, robust activity and good durability. A solar-to-HCOOH selectivity of 96.5% is obtained with a HCOOH yield of 108.2 mmol g−1 h−1 under bias-free illumination of AM1.5G. The device can operate stably for at least 12 h. In particular, an apparent photon quantum efficiency of 7.5% and a solar-to-chemical conversion efficiency (η SCC) of 8.3% are recorded, rivaling all the incumbent precious-metal-free all-solar-driven components for CO 2 -to-HCOOH conversion. This study highlights the potential of BOI-Bi for CO 2 to HCOOH conversion with high selectivity and its integration into APS system to realize carbon-negative solar-to-chemical conversion with industrial relevance. • The pathways of selectively converting H C O 3 – /CO 2 -to-HCOOH is simulated. • The gain effect of VBM for potential distribution in PEC system is clarified. • The cell voltage of optimized APS meets the highest selectivity for HCOOH. • The APS exhibits a highest η S C C of 8.3% in all the precious-metal-free devices. [ABSTRACT FROM AUTHOR]

D‐π‐A type 4‐((9‐phenylcarbazol‐3‐yl)ethynyl)‐N‐dodecyl‐1,8‐naphthalimide (CZNI) with a large dipole moment of 8.49 D and A‐π‐A type bis[(4,4′‐1,8‐naphthalimide)‐N‐dodecyl]ethyne (NINI) with a negligible dipole moment of 0.28 D, were smartly designed and synthesized to demonstrate the evidence of a molecular dipole as the dominant mechanism for controlling charge separation of organic semiconductors. In aqueous solution, these two novel naphthalimides can self‐assemble to form nanoribbons (NRs) that present significantly different traces of exciton dissociation dynamics. Upon photoexcitation of NINI‐NRs, no charge‐separated excitons (CSEs) are formed due to the large exciton binding energy, accordingly there is no hydrogen evolution. On the contrary, in the photoexcited CZNI‐NRs, the initial bound Frenkel excitons are dissociated to long‐lived CSEs after undergoing ultrafast charge transfer within ca. 1.25 ps and charge separation within less than 5.0 ps. Finally, these free electrons were injected into Pt co‐catalysts for reducing protons to H2 at a rate of ca. 417 μmol h−1 g−1, correspondingly an apparent quantum efficiency of ca. 1.3 % can be achieved at 400 nm. [ABSTRACT FROM AUTHOR]

D‐π‐A type 4‐((9‐phenylcarbazol‐3‐yl)ethynyl)‐N‐dodecyl‐1,8‐naphthalimide (CZNI) with a large dipole moment of 8.49 D and A‐π‐A type bis[(4,4′‐1,8‐naphthalimide)‐N‐dodecyl]ethyne (NINI) with a negligible dipole moment of 0.28 D, were smartly designed and synthesized to demonstrate the evidence of a molecular dipole as the dominant mechanism for controlling charge separation of organic semiconductors. In aqueous solution, these two novel naphthalimides can self‐assemble to form nanoribbons (NRs) that present significantly different traces of exciton dissociation dynamics. Upon photoexcitation of NINI‐NRs, no charge‐separated excitons (CSEs) are formed due to the large exciton binding energy, accordingly there is no hydrogen evolution. On the contrary, in the photoexcited CZNI‐NRs, the initial bound Frenkel excitons are dissociated to long‐lived CSEs after undergoing ultrafast charge transfer within ca. 1.25 ps and charge separation within less than 5.0 ps. Finally, these free electrons were injected into Pt co‐catalysts for reducing protons to H2 at a rate of ca. 417 μmol h−1 g−1, correspondingly an apparent quantum efficiency of ca. 1.3 % can be achieved at 400 nm. [ABSTRACT FROM AUTHOR]

Single‐atom metal‐insulator‐semiconductor (SMIS) heterojunctions based on Sn‐doped Fe2O3 nanorods (SF NRs) were designed by combining atomic deposition of an Al2O3 overlayer with chemical grafting of a RuOx hole‐collector for efficient CO2‐to‐syngas conversion. The RuOx‐Al2O3‐SF photoanode with a 3.0 nm thick Al2O3 overlayer gave a >5‐fold‐enhanced IPCE value of 52.0 % under 370 nm light irradiation at 1.2 V vs. Ag/AgCl, compared to the bare SF NRs. The dielectric field mediated the charge dynamics at the Al2O3/SF NRs interface. Accumulation of long‐lived holes on the surface of the SF NRs photoabsorber aids fast tunneling transfer of hot holes to single‐atom RuOx species, accelerating the O2‐evolving reaction kinetics. The maximal CO‐evolution rate of 265.3 mmol g−1 h−1 was achieved by integration of double SIMS‐3 photoanodes with a single‐atom Ni‐doped graphene CO2‐reduction‐catalyst cathode; an overall quantum efficiency of 5.7 % was recorded under 450 nm light irradiation. [ABSTRACT FROM AUTHOR]

Single‐atom metal‐insulator‐semiconductor (SMIS) heterojunctions based on Sn‐doped Fe2O3 nanorods (SF NRs) were designed by combining atomic deposition of an Al2O3 overlayer with chemical grafting of a RuOx hole‐collector for efficient CO2‐to‐syngas conversion. The RuOx‐Al2O3‐SF photoanode with a 3.0 nm thick Al2O3 overlayer gave a >5‐fold‐enhanced IPCE value of 52.0 % under 370 nm light irradiation at 1.2 V vs. Ag/AgCl, compared to the bare SF NRs. The dielectric field mediated the charge dynamics at the Al2O3/SF NRs interface. Accumulation of long‐lived holes on the surface of the SF NRs photoabsorber aids fast tunneling transfer of hot holes to single‐atom RuOx species, accelerating the O2‐evolving reaction kinetics. The maximal CO‐evolution rate of 265.3 mmol g−1 h−1 was achieved by integration of double SIMS‐3 photoanodes with a single‐atom Ni‐doped graphene CO2‐reduction‐catalyst cathode; an overall quantum efficiency of 5.7 % was recorded under 450 nm light irradiation. [ABSTRACT FROM AUTHOR]