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Electronic conduction can accelerate charge transfer, and metal–support interactions help improve the ability to resist CO poisoning, which are important features in methanol oxidation reaction (MOR) catalysis. Thus, an effective support that allows the modulation of electronic conduction and metal–support interactions is highly desired for catalyst construction. Herein, we demonstrate an effective catalyst system by coupling Pt nanoparticles (NPs) over N-doped carbon (NC)-modified hollow mesoporous-structured titanium nitride microporous sphere (H-TiN) supports for the MOR, in which NC acts as an important unit that regulates the electronic conduction in the catalyst and as an indispensable subassembly for protecting the hollow structures of H-TiN; in addition, the oxophilic properties of H-TiN and the strong metal–support interaction between Pt NPs and H-TiN endowed excellent CO poisoning resistance. The resulting Pt/H-TiN/NC-1.00 exhibited superior MOR activity with a mass activity of 1346 mA mgPt–1, which is 3.1 times higher than that of the Pt/C catalyst. Moreover, the Pt/H-TiN/NC-1.00 catalyst exhibited excellent antipoisoning ability toward CO in comparison to Pt/C catalysts. Our work provides more insights into optimizing the support for Pt NPs by modulating electronic conduction and metal–support interactions for direct methanol fuel cells with high MOR activity, excellent durability, and good CO tolerance ability. [ABSTRACT FROM AUTHOR]

As the most well-known electrocatalyst for cathodic hydrogen evolution in water splitting electrolyzers, platinum is unfortunately inefficient for anodic oxygen evolution due to its over-binding with oxygen species and excessive dissolution in oxidative environment. Herein we show that single Pt atoms dispersed in cobalt hydrogen phosphate with an unique Pt(OH)(O3)/Co(P) coordination can achieve remarkable catalytic activity and stability for oxygen evolution. The catalyst yields a high turnover frequency (35.1 ± 5.2 s−1) and mass activity (69.5 ± 10.3 A mg−1) at an overpotential of 300 mV and excellent stability. Mechanistic studies elucidate that the superior catalytic performance of isolated Pt atoms herein stems from optimal binding energies of oxygen intermediate and also their strong electronic coupling with neighboring Co atoms that suppresses the formation of soluble Ptx>4 species. Alkaline water electrolyzers assembled with an ultralow Pt loading realizes an industrial-level current density of 1 A cm−2 at 1.8 volts with a high durability. Platinum is the most active catalyst for cathodic hydrogen evolution, however it is inefficient for anodic oxygen evolution. Here, authors examine Pt single sites in cobalt hydrogen phosphate as oxygen evolution catalysts in water splitting electrolyzers. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) are one of the most popular photothermal agents (PTAs) as a noninvasive strategy for tumor treatment. However, because of the inherent dominant fluorescent emission, the CDs‐based PTAs hardly achieve a single photothermal conversion, which causes low photothermal conversion efficiency and poor photothermal performance. In this regard, finding a new CDs‐based material system to greatly restrain its fluorescence to enhance its photothermal conversion efficiency is highly required, however, it is still a grand challenge. Herein, a kind of Z‐scheme CDs‐based PTAs consisting of 2D ultrathin nonmetallic BxC/C Janus quantum sheets (BxC/C JQSs) is reported to greatly enhance the photothermal conversion efficiency. It is demonstrated that the heterogeneous growth of Z‐scheme BxC/C JQSs enables the NIR‐driven quick injection of hot electrons from C into the conjugated BxC, realizing a single conversion of light to heat, and resulting in a high photothermal conversion of 60.0% in NIR‐II. Furthermore, these new Z‐scheme BxC/C‐polyethylene glycol JQSs display outstanding biocompatibility and show effective tumor elimination outcome both in vitro and in vivo through the synergistic photothermal‐immunotherapy in the NIR‐II biowindow with undetectable harm to normal tissues. [ABSTRACT FROM AUTHOR]

Photothermal‐enhanced chemodynamic therapy is a novel and promising strategy for effective tumor treatment. Herein, a kind of polydopamine (PDA)‐based nanoplatform is reported for photothermal‐enhanced chemodynamic therapy against tumor cells. PDA nanoparticles (NPs) were prepared through the self‐polymerization method, which were subsequently chelated with Cu2+ and linked with poly(ethylene glycol) (PEG) chains, finally obtaining PDA‐Cu(II)‐PEG NPs. The fabricated PDA‐Cu(II)‐PEG NPs were uniform in shape with a narrow polydispersity. They can firstly react with glutathione (GSH) to generate Cu+, inducing GSH depletion meanwhile. The formed Cu+ could catalyze H2O2 to produce hydroxyl radicals (˙OH) via a Fenton‐like reaction. The formed PDA‐Cu(II)‐PEG NPs displayed good photothermal conversion efficiency and photothermal stability. They can be internalized by 4T1 cells effectively. Under near‐infrared light irradiation, PDA‐Cu(II)‐PEG NPs can generate hyperthermia and ˙OH for photothermal/chemodynamic therapy against tumor cells. [ABSTRACT FROM AUTHOR]