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The emergence of platinum‐based catalysts promotes efficient methanol oxidation reactions (MOR). However, the defects of such noble metal catalysts are high cost, easy poisoning, and limited commercial applications. The efficient utilization of a low‐cost, anti‐poisoning catalyst has been expected. Here, it is skillfully used N‐doped graphdiyne (NGDY) to prepare a zero‐valent platinum atomic catalyst (Pt/NGDY), which shows excellent activity, high pH adaptability, and high CO tolerance for MOR. The Pt/NGDY electrocatalysts for MOR with specific activity 154.2 mA cm−2 (1449.3 mA mgPt−1), 29 mA cm−2 (296 mA mgPt−1) and 22 mA cm−2 (110 mA mgPt−1) in alkaline, acid, and neutral solutions. The specific activity of Pt/NGDY is 9 times larger than Pt/C in alkaline solution. Density functional theory (DFT) calculations confirm that the incorporation of electronegativity nitrogen atoms can increase the high coverage of Pt to achieve a unique atomic state, in which the shared contributions of different Pt sites reach the balance between the electroactivity and the stability to guarantee the higher performance of MOR and durability with superior anti‐poisoning effect. [ABSTRACT FROM AUTHOR]

An iron vacancy‐rich ferroferric oxide/graphdiyne heterostructure (IVR‐FO/GDY) is rationally designed and fabricated for high‐efficiency electrocatalytic nitrogen fixation to ammonia (ENFA). Experimental and theoretical results show that the GDY‐induced iron vacancies in IVR‐FO/GDY promote the electrocatalysis, and activate the local O sites to transfer electrons towards GDY to boost ENFA, resulting in promising electrocatalytic performances with a highest ammonia yield (YNH3) of 134.02 µg h−1 mgcat.−1 and Faradaic efficiency (FE) of up to 60.88%, as well as the high long‐term stability in neutral electrolytes. The cationic vacancy activation strategy proposed in this work has strong general and universal guiding significance to the design of new efficient electrocatalysts for various electrochemical energy conversion reactions. Such defect engineering may be used efficiently in electrocatalysis, leading to the development and progress of energy industry. [ABSTRACT FROM AUTHOR]

Development of novel catalysts for nitrogen reduction at ambient pressures and temperatures with ultrahigh ammonia (NH3) yield and selectivity is challenging. In this work, an atomic catalyst with separated Pd atoms on graphdiyne (Pd-GDY) was synthesized, which shows fascinating electrocatalytic properties for nitrogen reduction. The catalyst has the highest average NH3 yield of 4.45 ± 0.30 mgNH3 mgPd−1 h−1, almost tens of orders larger than for previously reported catalysts, and 100% reaction selectivity in neutral media. Pd-GDY exhibits almost no decreases in NH3 yield and Faradaic efficiency. Density functional theory calculations show that the reaction pathway prefers to perform at the (Pd, C1, C2) active area because of the strongly coupled (Pd, C1, C2), which elevates the selectivity via enhanced electron transfer. By adjusting the p–d coupling accurately, reduction of self-activated nitrogen is promoted by anchoring atom selection, and side effects are minimized. [ABSTRACT FROM AUTHOR]

A highly active graphdiyne heterojunction with highly efficient photocatalysis is designed and fabricated. This catalyst demonstrates transformative properties on photocatalysis for ammonia synthesis. Such excellent properties are reigned from graphdiyne incorporating Fe site‐specific magnetite resulting in a valence state transition within the catalyst. Our results show the strong advantages of graphdiyne in effectively regulating magnetite activity and coordination environments and also indicate that magnetite can selectively form two different valence tetrahedral coordination Fe and octahedral coordination Fe. The catalysts show remarkable catalytic performance for ammonia synthesis by photocatalysis, indicating transformative photocatalytic activity with an ammonia yield (YNH3) of unprecedented level of 1762.35±153.71 μmol h−1 gcat.−1 (the highest YNH3 could reach up to 1916.06 μmol h−1 gcat.−1). This work makes full use of the structural and property features of graphdiyne and opens up a new direction for photocatalysis in the field of catalysis. [ABSTRACT FROM AUTHOR]

Abstract: The first utilization of nitrogen‐doped graphdiyne (NGDY) as an efficient catalytic promoter for hydrogen evolution reaction (HER) is reported. X‐ray powder diffraction and X‐ray photoelectron spectroscopy studies indicate the presence of strong interactions between NGDY and MoS2, which should effectively facilitate the charge transport behavior and improvement of the HER kinetics. The creative hybridization of MoS2 and NGDY endows such heterostructure with structural and compositional advantages for boosting the catalytic activity (low overpotential of 186 mV at 10 mA cm−2 and Tafel slope of 63 mV dec−1) and extraordinary stability (higher than all reported MoS2‐based materials and even better than that of commercial Pt and almost all benchmarked electrocatalysts). All of the results not only demonstrate that NGDY can be used as an effective catalytic promoter for hydrogen production, but also provide new strategy for fabricating efficient water‐splitting electrodes. [ABSTRACT FROM AUTHOR]

The present study focused on the degradation of sulfamethoxazole (SMX) aqueous solution and the toxicity of processing aqueous by the dielectric barrier discharge (DBD) activated persulfate (PS). The effects of input voltage, input frequency, duty cycle, and PS dosage ratio on the SMX degradation efficiency were measured. Based on the results of the Response Surface Methodology (RSM), SMX degradation efficiency reached 83.21% which is 10.54% higher than that without PS, and the kinetic constant was 0.067 min -1 in 30 min when the input voltage at 204 V (input power at 110.6 W), the input frequency at 186 Hz, the duty cycle at 63%, and the PS dosage ratio at 5.1:1. The addition of PS can produce more active particles reached 1.756 mg/L (O 3 ), 0.118 mg/L (H 2 O 2 ), 0.154 mmol/L (·OH) in 30 min. Furthermore, the DBD plasma system effectively activated an optimal amount of PS, leading to improved removal efficiency of COD, and TOC to 30.21% and 47.21%, respectively. Subsequently, eight primary by-products were pinpointed, alongside the observation of three distinct pathways of transformation. Predictions from the ECOSAR software indicated that most of the degradation intermediates were less toxic than SMX. The biological toxicity experiments elucidated that the treatment with the DBD/PS system effectively reduced the mortality of zebrafish larvae caused by SMX from 100% to 20.13% and improved the hatching rate from 55.69% to 80.86%. In particular, it is important to note that the degradation intermediates exhibit teratogenic effects on zebrafish larvae.

A freestanding 3D graphdiyne-cobalt nitride (GDY/Co 2 N) with a highly active and selective interface is fabricated for the electrochemical nitrogen reduction reaction (ECNRR). Density function theory calculations reveal that the interface-bonded GDY contributes an unique p-electronic character to optimally modify the Co-N compound surface bonding, which generates as-observed superior electronic activity for NRR catalysis at the interface region. Experimentally, at atmospheric pressure and room temperature, the electrocatalyst creates a new record of ammonia yield rate (Y NH 3 ) and Faradaic efficiency (FE) of 219.72 μg h -1  mg cat. -1 and 58.60 %, respectively, in acidic conditions, higher than reported electrocatalysts. Such a catalyst is promising to generate new concepts, new knowledge, and new phenomena in electrocatalytic research, driving rapid development in the field of electrocatalysis., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A highly efficient bifunctional metal-free catalyst was prepared by growth of three-dimensional porous fluorographdiyne networks on carbon cloth (p-FGDY/CC). Our experiments and density functional theory (DFT) calculations show the 3D p-FGDY/CC network is highly active and it is a high potential metal-free catalyst for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), as well as overall water splitting (OWS) under both acidic and alkaline conditions. The experimental and theoretical results show very good consistency; for example, in the HER process, p-FGDY/CC exhibits small overpotentials of 82 and 92 mV to achieve 10 mA cm -2 under alkaline and acidic conditions, respectively. This ensures an even higher selectivity for the adsorption/desorption of various O/H intermediate species. The essential key promotion accomplishes a bifunctional H 2 O redox performance application under pH-universal electrochemical conditions., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)