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Defects engineering is significant for photocatalytic environment remediation. To this end, visible‐light‐driven α‐Fe2O3/ZrO2‐x S‐scheme heterojunction photocatalysts with optimal oxygen vacancy (Ov) defects are successfully synthesized via a two‐step method. Compared with pristine UiO‐66‐NH2‐derived ZrO2‐x and α‐Fe2O3, the heterojunction photocatalysts exhibit a wider range of visible light response and higher efficiency in separating photogenerated electron–hole pairs. Among them, the 5% α‐Fe2O3/ZrO2‐x sample shows the best photocatalytic performance to the degradation of tetracycline (TC) (89.3%), in which the pseudo‐first‐order kinetic rate constants are 8.20 and 16.75 times that of pristine ZrO2‐x and α‐Fe2O3, respectively. The outstanding photocatalytic degradation efficiency can be attributed to both the narrow‐bandgap ZrO2‐x with visible light response and the formation of α‐Fe2O3/ZrO2‐x S‐scheme heterojunctions. During the formation of heterojunctions, the concentration of oxygen vacancies (Ov) at the interface of α‐Fe2O3/ZrO2‐xdecreases monotonically with the increasing loading of α‐Fe2O3, thereby altering the electronic structure of the photocatalyst and forming the heterojunction firmly. In addition, the high stability implies the potential applications in fields of environment. [ABSTRACT FROM AUTHOR]

Actiniae‐like carbon nitride (ACN) bundles were synthesized by the pyrolysis of an asymmetric supramolecular precursor prepared from L‐arginine (L‐Arg) and melamine. ACN has adjustable band gaps (2.25 eV–2.75 eV) and hollow microtubes with ultrathin pore walls, which enrich reaction sites, improve visible‐light absorption and enhance charge separation. In the presence of phenylcarbinol, ACN exhibited excellent water‐splitting ability (95.3 μmol h−1) and in the meanwhile phenylcarbinol was selectively oxidized to benzaldehyde (conversion of 90.9 %, selectivity of 99.7 %) under solar irradiation. For the concurrent reactions, 2D isotope labeling, separation, and detection were conducted to confirm that the proton source of released hydrogen is water. The mechanism of water splitting and phenylcarbinol oxidation was also investigated. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (GCN) has become an attractive photocatalyst for solar energy conversion, but the photocatalytic activity of GCN is still limited by the extremely fast electron–hole recombination. Herein, a defective ultrathin mesoporous graphitic carbon nitride (DUMCN) photocatalyst with high specific surface area and mesoporous structure is fabricated through a facile three‐step heat‐treatment strategy, which reduces the distance of bulk photogenerated carriers to the surface, resulting in efficient adsorption and diffusion of reactants and products, and exposing adequate surface active sites. Moreover, suitable N‐vacancy defects are formed via high‐temperature surface hydrogenation, which can extend light absorption and produce ultra‐high intrinsic carrier mobility, and further increase the active sites. The photocatalytic hydrogen production rate is up to 13.63 mmol h−1 g−1 under visible light in the triethanolamine solution and 33.5 μmol h−1 g−1 for overall water splitting, which is much higher than that of bulk graphitic carbon nitride (BCN) structures. Density functional theory (DFT) calculations further reveal the effect of surface defects on the band structure for promoting the spatial charge separation. This facile strategy may offer new insights into designing other ultrathin mesoporous semiconductor photocatalysts with high performance. [ABSTRACT FROM AUTHOR]

Carbon nitride, phenylcarbinol oxidation, photocatalysis, supramolecular assembly, water splitting Keywords: carbon nitride; phenylcarbinol oxidation; photocatalysis; supramolecular assembly; water splitting EN carbon nitride phenylcarbinol oxidation photocatalysis supramolecular assembly water splitting 5003 5003 1 02/18/21 20210223 NES 210223 B Die synchrone und effiziente b Nutzung von photogenerierten Elektronen und Löchern ist eine herausfordernde Aufgabe auf dem Gebiet der Photokatalyse. Innenrücktitelbild: Ultrathin Porous Carbon Nitride Bundles with an Adjustable Energy Band Structure toward Simultaneous Solar Photocatalytic Water Splitting and Selective Phenylcarbinol Oxidation (Angew. [Extracted from the article]

Nanoformulations with endogenous/exogenous stimulus‐responsive characteristics show great potential in tumor cell elimination with minimal adverse effects and high precision. Herein, an intelligent nanotheranostic platform (denoted as TPZ@Cu‐SnS2‐x/PLL) for tumor microenvironment (TME) and near‐infrared light (NIR) activated tumor‐specific therapy is constructed. Copper (Cu) doping and the resulting sulfur vacancies can not only improve the response range of visible light but also improve the separation efficiency of photogenerated carriers and increase the carrier density, resulting in the ideal photothermal and photodynamic performance. Density functional theory calculations revealed that the introduction of Cu and resulting sulfur vacancies can induce electron redistribution, achieving favorable photogenerated electrons. After entering cells through endocytosis, the TPZ@Cu‐SnS2‐x/PLL nanocomposites show the pH responsivity property for the release of the TPZ selectively within the acidic TME, and the released Cu2+ can first interact with local glutathione (GSH) to deplete GSH with the production of Cu+. Subsequently, the Cu+‐mediated Fenton‐like reaction can decompose local hydrogen peroxide into hydroxyl radicals, which can also be promoted by hyperthermia derived from the photothermal effect for tumor cell apoptosis. The integration of photoacoustic/computed tomography imaging‐guided NIR phototherapy, TPZ‐induced chemotherapy, and GSH‐elimination/hyperthermia enhanced chemodynamic therapy results in synergistic therapeutic outcomes without obvious systemic toxicity in vivo. [ABSTRACT FROM AUTHOR]