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Amino acids are the building blocks of proteins and are widely used as important ingredients for other nitrogen‐containing molecules. Here, we report the sustainable production of amino acids from biomass‐derived hydroxy acids with high activity under visible‐light irradiation and mild conditions, using atomic ruthenium‐promoted cadmium sulfide (Ru1/CdS). On a metal basis, the optimized Ru1/CdS exhibits a maximal alanine formation rate of 26.0 molAla ⋅ gRu−1 ⋅ h−1, which is 1.7 times and more than two orders of magnitude higher than that of its nanoparticle counterpart and the conventional thermocatalytic process, respectively. Integrated spectroscopic analysis and density functional theory calculations attribute the high performance of Ru1/CdS to the facilitated charge separation and O−H bond dissociation of the α‐hydroxy group, here of lactic acid. The operando nuclear magnetic resonance further infers a unique "double activation" mechanism of both the CH−OH and CH3−CH−OH structures in lactic acid, which significantly accelerates its photocatalytic amination toward alanine. [ABSTRACT FROM AUTHOR]

Modification and functionalization of porous aromatic framework (PAF) materials have emerged as crucial research directions in various fields. In this study, we employed a hydrothermal method to synthesize a carbon quantum dots (CQDs) solution. By loading different amounts of CQDs onto the surface of PAF-45 material through ultrasonic and hydrothermal treatments, we successfully formed CQDs/PAF-45 composite materials. The introduction of CQDs effectively transformed the hydrophobic nature of PAF-45 into a hydrophilic material, thereby overcoming the challenge of achieving efficient contact between PAF catalysts and reactants in aqueous solutions. In the photocatalytic degradation experiments of Rhodamine B (RhB), tetracycline, CQDs/PAF-45 composite materials surpassed that of the pristine PAF-45 material. Notably, the 1 wt% CQDs/PAF-45 composite material exhibited the highest photocatalytic activity, with degradation efficiencies for Rhodamine B, tetracycline, and phenol approximately 1.4 times, 1.5 times and 1.5 times higher than those of the PAF-45 material, respectively. [ABSTRACT FROM AUTHOR]

Solar‐driven selective oxygen reduction reaction on polymeric carbon nitride framework is one of the most promising approaches toward sustainable H2O2 production. Potassium poly(heptazine imide) (PHI), with regular metal sites in the framework and favorable crystalline structure, is highly active for photocatalytic selective 2e oxygen reduction to produce H2O2. By introducing NH4Cl into the eutectic KCl‐LiCl salt mixture, the PHI framework exhibits a remarkable performance for photocatalytic production of H2O2, for example, a record high H2O2 photo‐production rate of 29.5 μmol h−1 mg−1. The efficient photocatalytic performance is attributed to the favorable properties of the new PHI framework, such as improved porosity, negatively shifted LUMO position, enhanced exciton dissociation and charges migration properties. A mechanistic investigation by quenching and electron spin resonance technique reveals the critical role of superoxide radicals for the formation singlet oxygen, and the singlet oxygen is one of the critical intermediates towards the formation of the H2O2 by proton extraction from the ethanol. [ABSTRACT FROM AUTHOR]

Defects in nanomaterials often lead to properties that are absent in their pristine counterparts. To date, most studies have focused on the effect of single defects, while ignoring the synergy of multiple defects. In this study, a model of photocatalytic O2 activation was selected to unravel the role of dual defects by decorating bismuth oxide with surface O vacancies and bulk O substitution simultaneously. The introduction of dual defects led to a spatial and electronic synergistic process: i) O substitution induced a local electric field in the bulk of BiO2−x, which promoted bulk separation of electrons and holes immediately after their generation; ii) O vacancies efficiently lowered the conduction band, served as the capture center for electrons, and thus facilitated the adsorption and activation of O2. This effect was greatly promoted by the coexistence of bulk O substitution, and DFT calculations showed that only O substitution near an O vacancy could have this effect. [ABSTRACT FROM AUTHOR]

A highly efficient Z‐scheme photocatalytic system constructed with 1D CdS and 2D CoS2 exhibited high photocatalytic hydrogen‐evolution activity of 5.54 mmol h−1 g−1 with an apparent quantum efficiency of 10.2 % at 420 nm. More importantly, its interfacial charge migration pathway was unraveled: The electrons are efficiently transferred from CdS to CoS2 through a transition atomic layer connected by Co–S5.8 coordination, thus resulting in more photogenerated carriers participating in surface reactions. Furthermore, the charge‐trapping and charge‐transfer processes were investigated by transient absorption spectroscopy, which gave an estimated charge‐separation yield of approximately 91.5 % and a charge‐separated‐state lifetime of approximately (5.2±0.5) ns in CdS/CoS2. This study elucidates the key role of interfacial atomic layers in heterojunctions and will facilitate the development of more efficient Z‐scheme photocatalytic systems. [ABSTRACT FROM AUTHOR]

A new photocatalytic reaction process is described that cyano groups ( CN) are successfully grafted on carbon nitride (g-C 3 N 4 materials). The cyano group substitutes the previous surface terminating amino group ( NH 2 ) on g-C 3 N 4 by a radical reaction pathway, modifying the electron structure of the conjugated covalent system and engendering favorable properties for the visible-light driven photocatalysis. Cyanidated g-C 3 N 4 (g-C 3 N 4 -xCN) has a narrowed band gap of 2.29 eV, as compared to 2.73 eV for the pristine g-C 3 N 4 , showing expanded visible light absorbance to 590 nm. Moreover, the photo-induced charge-carrier separation is improved as well. In consequence, g-C 3 N 4 -xCN exhibits significantly enhanced performance in photocatalysis, here exemplifyed with the model coupling reaction towards alkenyl sulfones under green light (520 nm) irradiation. The methodology reported herein reveals the potential of the carbon nitride scaffold to be modified as such and illustrates the possiblities of the as-created novel carbon nitride materials grafted with various functional groups on their surface. [ABSTRACT FROM AUTHOR]

Titanium dioxide with surface-loaded palladium (Pd-TiO2) was able to easily remove all ten bromine atoms from decabromodiphenyl ether (BDE209) within 1 h under the irradiation of sunlight or an artificial light source. By contrast, fewer than three bromine atoms were eliminated on the pristine TiO2 even with prolonged irradiation (5 h). During the photocatalytic debromination, moreover, the formed BDE intermediates exhibited a significant difference between the Pd-TiO2 and pristine TiO2 systems, and much less position selectivity for the debromination on Pd-TiO2 was observed than that on the pristine TiO2 surface. For another polybrominated diphenyl ether (BDE15), pristine TiO2 was incapable of its photocatalytic reduction, whereas the loading of Pd enabled its debromination to diphenyl ether within 20 min. In addition, an evident induction period appeared in the photocatalytic debromination of BDE15 on Pd-TiO2. The experiments imply that the Pd-cocatalyzed effect changes significantly the photocatalytic reductive debromination pathways. [ABSTRACT FROM AUTHOR]

An iron(iii)-mediated photocatalytic method for the conversion of aryl, heteroaryl and polycyclic aromatic bromides to the corresponding chlorides with high selectivity has been achieved successfully. The mild reaction conditions and high chloride utilization efficiency promise a bright future for chlorination reactions. [ABSTRACT FROM AUTHOR]

For the first time, aluminum alloy was used as the main source to prepare aluminum oxide-modified carbon nitride with a melamine–cyanuric acid supramolecular complex. The introduction of amorphous aluminum oxide confers macroporosity to the skeletons of g-C3N4-AlOx. Its surface area increased to 75.5 m2g−1, about 1.5 times that of single g-C3N4. After modification, the visible light response range was expanded, especially at 450~500 nm, while the band structure could be adjusted. Compared with g-C3N4, g-C3N4-AlOx has better photocatalytic performance, the adsorption rate for the dye rhodamine B (RhB) is about 2.1 times that of g-C3N4, and the RhB removal rate is 1.2 times that of g-C3N4. [ABSTRACT FROM AUTHOR]

TiO2 with the merits of non‐toxicity, high stability, strong redox capability, and low cost, has garnered considerable attention in the fields of renewable energy. However, the practical application is limited by the rapid recombination of photogenerated electron–hole pairs, posing a challenge to enhance electron utilization without compromising catalytic activity. Herein, S‐scheme TiO2@Co(OH)F‐Pt heterojunction through a simple hydrothermal and photo‐deposition method is constructed. The experimental tests and theoretical computation indicate that Co(OH)F possesses a smaller work function and a more negative conduction band (CB) position, significantly accelerating the separation of photogenerated charge carriers. Furthermore, the built‐in electric field, band bending between TiO2 and Co(OH)F, and the electron sink of Pt nanoparticles, facilitate the reduction of protons to hydrogen. The as‐prepared TiO2@Co(OH)F‐Pt exhibits high‐performance solar hydrogen evolution with an evolution rate of 1401 µmol h−1. The apparent quantum yield (AQY) is determined to be 22.8% at a single wavelength of 365 nm. After reacting 12 h for three cycles, no noticeable performance degradation occurs, showing good stability of the catalyst. This work provides a rational strategy for the design of heterojunction photocatalysts for driving the production of new energy and useful chemicals. [ABSTRACT FROM AUTHOR]

When the advancement of conventional heterojunctions is restricted by lattice matching of materials, Van der Waals heterojunctions formed by interlayer Van der Waals force present enormous development prospects with the revolution of graphene and graphene-like materials. Ascribed to similar graphene-like structures, carbonized polymer dots (CPDs) and potassium-doped carbon nitride nanosheets (KCNNS) were stacked by the ball milling method to form a novel Van der Waals heterojunction. Experimental analysis and density functional theory (DFT) calculations demonstrate that the constructed CPDs/KCNNS heterojunctions can effectively suppress sluggish reaction dynamics. CPDs/KCNNS-2 composites demonstrate enhanced CO 2 photoreduction performance (78.98 μmol g−1∙h−1) with 100% CO selectivity in pure water, which is 13.71 times higher than that of KCNNS. In-situ FT-IR spectra were employed to identify the intermediates formed in the CO evolution process of CPDs/KCNNS composites. The manuscript provides a scientific reference for the stacking of Van der Waals heterojunction based on C 3 N 4 in the artificial photosynthesis field. [Display omitted] • CPDs/KCNNS composites were prepared by the ball milling method. • CPDs/KCNNS-2 composites have high CO 2 photoreduction rate (78.98 μmol g−1∙h−1). • CPDs/KCNNS-2 composites have high stability, selectivity, and AQE (0.86%@400 nm). • The possible CO generation pathway is proposed by intermediates analysis. [ABSTRACT FROM AUTHOR]

Ru(H2dcbpy)32+, one of the Ru(bpy)32+(dcbpy= 2,2′-bipyridine-4,4′-dicarboxylicacid, bpy = 2,2′-bipyridine) derivatves, has been used as apropeller-like photoactive metalloligand to coordinate with indium(III)ions to form a highly symmetric metal–organic framework [InRu(dcbpy)3][(CH3)2NH2]·6H2O (1), and the cubic microcrystals of 1have been acquired through modified procedures. Compound 1manifests broad visible light absorption band and strong red lightemission with long decay lifetime, both of which are originated fromthe metal-to-ligand charge transfer of the Ru(dcbpy)34–metalloligands. Because of the highly light-harvestingand strong redox nature of the Ru(dcbpy)32+unitsin 1, its photocatalysis activities were determined byvisible light-induced photodegradation of methyl orange experiments.The results indicate that 1can be a stable and goodvisible-light driving heterogeneous photocatalyst. Meanwhile, thesensing properties of 1were also evaluated, and theresult shows that 1can selectively detect the nitroexplosives molecules. [ABSTRACT FROM AUTHOR]

• The Fe-doped Bi 12 O 17 Cl 2 nanotube is synthesized successfully. • The Fe-doped Bi 12 O 17 Cl 2 can harvest the visible, full-spectrum, and near-infrared light. • The Fe-doped Bi 12 O 17 Cl 2 performs enhanced photocatalytic degradation activity of water pollutant. Full-spectrum responsive and effective charge separation efficiency are still important factors for enhanced photocatalytic activity. Herein, a one-dimensional Bi 12 O 17 Cl 2 nanotube (Fe-Bi 12 O 17 Cl 2) has been synthesized successfully, which could simultaneously expand the ability of light absorption and charge separation. As the results, Fe-Bi 12 O 17 Cl 2 could realize the degradation of rhodamine B (RhB) pollutants under near-infrared and full-spectrum light irradiation, and compared with Bi 12 O 17 Cl 2 nanotube, the photocatalytic performance was improved by 3.49 and 1.93 times, respectively. Mechanism studies have shown that the Fe-doped strategy could introduce variable valence Fe3+, forming a Fe2+/Fe3+ cycle, which promotes efficient charge transfer and further enhances the activity of the photocatalytic reaction. Overall, this work provides new sight into the design of high-performance photocatalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • A nearly total conversion and > 98% selectivity of C-C bond cleavage is achieved. • Sufficient superoxide radicals are necessary for highly selective C-C bond cleavage under visible light. • Efficient photocatalytic C-C bonds breaking towards lignin β -O-4 model compounds. • Ru single atoms outperform the nanoparticles for photocatalytic C-C bond cleavage. • C β -H extraction by photogenerated hole is the critical step of the transformation. The selective cleavage of the C C bonds in lignin is highly pursued to obtain aromatic monomers from renewable resources but remains challenging due to their high dissociation energies and steric hindrance between bulky aromatic groups. Herein, a mesoporous carbon nitride-supported ruthenium single-atom photocatalyst (Ru 1 /MCN) is reported for efficient oxidative C α -C β bonds scissoring towards lignin β -O-4 model compounds with high activity and selectivity under visible–light irradiation and room temperature. With this strategy, a nearly total conversion of > 99% and > 98% selectivity of C C bond cleavage can be achieved upon 2–phenoxy–1–phenylethanol. In-depth investigations verify that the C β -H extraction by photogenerated holes is the critical step of the transformation, which directly generates the C β radical intermediates and thus promotes the selective C α -C β bonds breaking by coupling with superoxide radicals induced by photogenerated electrons. This work explores the potential of single-atom catalysts for photocatalytic production of aromatics from renewable biomass feedstocks. [ABSTRACT FROM AUTHOR]

Photocatalytic technology is considered to be one of the most promising technologies for the removal of organic contaminants. Conjugated Microporous Polymers and their composites are considered to be an effective material for degrading antibiotic contamination, due to their high specific surface area, excellent chemical stability and certain photocatalytic activity. Herein, we synthesized a new type of CMP composite material (PAF-Mt) with montmorillonite template to improve the photocatalytic properties. The results showed that the incorporation of montmorillonite template adjusted electronic band structures of final material, significantly enhanced its photocatalytic activity, and showed excellent photocatalytic efficiency for ofloxacin, tetracycline, ciprofloxacin and chloramphenicol. The efficiencies got increased markedly (325% to 766%) compared to the PAFs without template addition. [Display omitted] • A conjugated microporous polymer with excellent photocatalytic properties was synthesized with montmorillonite template. • The montmorillonite template influenced the polymerization mode and significantly improved the photocatalytic performance. • PAF-Mt has remarkable photocatalytic degradation effect on ofloxacin, tetracycline, ciprofloxacin and chloramphenicol. [ABSTRACT FROM AUTHOR]

Porous aromatic framework (PAF) materials with π-π conjugation system based on Scholl reaction were found to exhibit satisfying photocatalytic performance, that can successfully degrade Rhodamine B (RhB) and colorless phenol. By selecting different multiple-phenyl building blocks, six kinds of PAF materials named as P-BP materials were successfully constructed by Scholl reaction, which exhibit not only photocatalytic ability, but also moderate specific surface areas, wide solar spectrum coverage, and good thermal and chemical stabilities. Depending on their different building block selections, the photocatalytic performance can be adjusted. The P-BP-DPA was found to exhibit the highest photocatalytic performance with 100% and 50% degradation rate for RhB and phenol in 300 min, respectively. Free radical trapping experiments showed that the photocatalytic activity originated from the strong oxidation capability of photogenerated holes. The band structure of such group of materials can be readily adjusted. With different monomers, their band gaps can be tuned from 1.87 to 2.36 eV, and their valence band positions were adjusted from 1.93 to 3.44 eV (vs NHE). The P-BP materials were prepared via Scholl reaction and active photocatalysts were designed in the degrdation of RhB and phenol. Unlabelled Image • Porous aromatic framework materials were prepared with Scholl reaction. • The PAFs were active in degradation of Rhodamine B and colorless phenol. • Adjusted photocatalytic performance was achieved by building blocks selection. • Band gaps can be tuned from 1.87 to 2.36 eV, and valence band positions can be adjusted from 1.93 to 3.44 eV. [ABSTRACT FROM AUTHOR]