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BiOCl photocatalysis shows great promise for molecular oxygen activation and NO oxidation, but its selective transformation of NO to immobilized nitrate without toxic NO 2 emission is still a great challenge, because of uncontrollable reaction intermediates and pathways. In this study, we demonstrate that the introduction of triangle Cl-Ag 1 -Cl sites on a Cl-terminated, (001) facet-exposed BiOCl can selectively promote one-electron activation of reactant molecular oxygen to intermediate superoxide radicals (⋅O 2 - ), and also shift the adsorption configuration of product NO 3 - from the weak monodentate binding mode to a strong bidentate mode to avoid unfavorable photolysis. By simultaneously tuning intermediates and products, the Cl-Ag 1 -Cl-landen BiOCl achieved >90 % NO conversion to favorable NO 3 - of high selectivity (>97 %) in 10 min under visible light, with the undesired NO 2 concentration below 20 ppb. Both the activity and the selectivity of Cl-Ag 1 -Cl sites surpass those of BiOCl surface sites (38 % NO conversion, 67 % NO 3 - selectivity) or control O-Ag 1 -O sites on a benchmark photocatalyst P25 (67 % NO conversion and 87 % NO 3 - selectivity). This study develops new single-atom sites for the performance enhancement of semiconductor photocatalysts, and also provides a facile pathway to manipulate the reactive oxygen species production for efficient pollutant removal., (© 2023 Wiley-VCH GmbH.)

Cobalt ferrite (CoFe 2 O 4 ) spinel has been found to produce C 2 -C 4 hydrocarbons in a single-step, ambient-pressure, photocatalytic hydrogenation of CO 2 with a rate of 1.1 mmol g -1  h -1 , selectivity of 29.8 % and conversion yield of 12.9 %. On stream the CoFe 2 O 4 reconstructs to a CoFe-CoFe 2 O 4 alloy-spinel nanocomposite which facilitates the light-assisted transformation of CO 2 to CO and hydrogenation of the CO to C 2 -C 4 hydrocarbons. Promising results obtained from a laboratory demonstrator bode well for the development of a solar hydrocarbon pilot refinery., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Seawater is one of the most important CO 2 sequestration media for delivering value-added chemicals/fuels and active chlorine; however, this scenario is plagued by sluggish reaction rates and poor product selectivity. Herein, we first report the synthesis of nitrogen-doped BiOCl atomic layers to directly split carbon-sequestrated natural seawater (Yellow Sea, China) into stoichiometric CO (92.8 μmol h -1 ) and HClO (83.2 μmol h -1 ) under visible light with selectivities greater than 90 %. Photoelectrons enriched on the exposed BiOCl{001} facet kinetically facilitate CO 2 -to-CO reduction via surface-doped nitrogen bearing Lewis basicity. Photoholes, mainly located on the lateral facets of van der Waals gaps, promote the selective oxidation of Cl - into HClO. Sequestrated CO 2 also maintains the pH of seawater at around 4.2 to prevent the alkaline earth cations from precipitating. The produced HClO can effectively kill typical bacteria in the ballast water of ocean-going cargo ships, offering a green and safe way for onsite sterilization., (© 2023 Wiley-VCH GmbH.)

Urea, an agricultural fertilizer, nourishes humanity. The century-old Bosch-Meiser process provides the world's urea. It is multi-step, consumes enormous amounts of non-renewable energy, and has a large CO 2 footprint. Thus, developing an eco-friendly synthesis for urea is a priority. Herein we report a single-step Pd/LTA-3A catalyzed synthesis of urea from CO 2 and NH 3 under ambient conditions powered solely by solar energy. Pd nanoparticles serve the dual function of catalyzing the dissociation of NH 3 and providing the photothermal driving force for urea formation, while the absorption capacity of LTA-3A removes by-product H 2 O to shift the equilibrium towards urea production. The solar urea conversion rate from NH 3 and CO 2 is 87 μmol g -1  h -1 . This advance represents a first step towards the use of solar energy in urea production. It provides insights into green fertilizer production, and inspires the vision of sustainable, modular plants for distributed production of urea on farms., (© 2021 Wiley-VCH GmbH.)

The objective of photocatalytic CO 2 reduction (PCR) is to achieve high selectivity for a single energy-bearing product with high efficiency and stability. The bulk configuration usually determines charge carrier kinetics, whereas surface atomic arrangement defines the PCR thermodynamic pathway. Concurrent engineering of bulk and surface structures is therefore crucial for achieving the goal of PCR. Herein, an ultrastable and highly selective PCR using homogeneously doped BiOCl nanosheets synthesized via an inventive molten strategy is presented. With B 2 O 3 as both the molten salt and doping precursor, this new doping approach ensures boron (B) doping from the surface into the bulk with dual functionalities. Bulk B doping mitigates strong excitonic effects confined in 2D BiOCl by significantly reducing exciton binding energies, whereas surface-doped B atoms reconstruct the BiOCl surface by extracting lattice hydroxyl groups, resulting in intimate B-oxygen vacancy (B-OV) associates. These exclusive B-OV associates enable spontaneous CO 2 activation, suppress competitive hydrogen evolution and promote the proton-coupled electron transfer step by stabilizing *COOH for selective CO generation. As a result, the homogeneous B-doped BiOCl nanosheets exhibit 98% selectivity for CO 2 -to-CO reduction under visible light, with an impressive rate of 83.64 µmol g -1 h -1 and ultrastability for long-term testing of 120 h., (© 2021 Wiley-VCH GmbH.)

Removal of non-biodegradable heavy metals has been the top priority in wastewater treatment and the development of green technologies remains a significant challenge. We demonstrate that phosphorylated nanoscale zero-valent iron (nZVI) is promising for removal of heavy metals (Ni II , Cu II , Cr VI , Hg II ) via a boosted Kirkendall effect. Phosphorylation confines tensile hoop stress on the nZVI particles and "breaks" the structurally dense spherical nZVI to produce numerous radial nanocracks. Exemplified by Ni II removal, the radial nanocracks favor the facile inward diffusion of Ni II and the rapid outward transport of electrons and ferrous ions through the oxide shell for surface (Ni II /electron) and boundary (Ni II /Fe 0 ) galvanic exchange. Accompanied by a pronounced hollowing phenomenon, phosphorylated nZVI can instantly reduce and immobilize Ni II throughout the oxide shell with a high capacity (258 mg Ni g -1  Fe). For real electroplating factory wastewater treatment, this novel nZVI performs simultaneous Ni II and Cu II removal, producing effluent of stable quality that meets local discharge regulations., (© 2021 Wiley-VCH GmbH.)

Nanoscale titanium nitride TiN is a metallic material that can effectively harvest sunlight over a broad spectral range and produce high local temperatures via the photothermal effect. Nanoscale indium oxide-hydroxide, In 2 O 3- x (OH) y , is a semiconducting material capable of photocatalyzing the hydrogenation of gaseous CO 2 ; however, its wide electronic bandgap limits its absorption of photons to the ultraviolet region of the solar spectrum. Herein, the benefits of both nanomaterials in a ternary heterostructure: TiN@TiO 2 @In 2 O 3- x (OH) y are combined. This heterostructured material synergistically couples the metallic TiN and semiconducting In 2 O 3- x (OH) y phases via an interfacial semiconducting TiO 2 layer, allowing it to drive the light-assisted reverse water gas shift reaction at a conversion rate greatly surpassing that of its individual components or any binary combinations thereof., (© 2020 Wiley-VCH GmbH.)