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Developing high‐performance Pt‐based catalysts with strong metal‐support interaction (SMSI) is significant for hydrogen production by water electrolysis working at high current density conditions, but still challenging. Herein, Pt/X‐NCNT (X = 4, 8, 12, 16) with SMSI is designed and developed by combining the advantages of Platinum‐based catalysts and nitrogen‐doped carbon material. In‐situ and ex‐situ experiments and density functional theory simulations illustrate that the Gibbs free energies (ΔG) of reaction intermediates (H2O*, OH*, H*) are optimized by the synergistic effect of various N functional groups and Pt under SMSI. The Pt/8‐NCNT only needs overpotentials of 17, 107, and 153 mV to reach current densities of 10, 500, and 1000 mA cm−2. Concurrently, the Pt/8‐NCNT exhibits brilliant stability after 100 h current–time (i–t) tests at 500 mA cm−2. More importantly, this work demonstrates the function of pyrrolic‐N and pyridinic‐N in the reaction, and provides new ideas for the design of advanced SMSI electrocatalysts for various electrochemical and catalytic applications. [ABSTRACT FROM AUTHOR]

Direct ethanol fuel cells are among the most efficient and environmentally friendly energy‐conversion devices and have been widely focused. The ethanol oxidation reaction (EOR) is a multielectron process with slow kinetics. The large amount of by‐product generated by incomplete oxidation greatly reduces the efficiency of energy conversion through the EOR. In this study, a novel type of trimetallene called porous PdWM (M = Nb, Mo and Ta) is synthesized by a facile method. The mass activity (15.6 A mgPd−1) and C1 selectivity (55.5%) of Pd50W27Nb23/C trimetallene, obtained after optimizing the compositions and proportions of porous PdWM, outperform those of commercial Pt/C (1.3 A mgPt−1, 5.9%), Pd/C (5.0 A mgPd−1, 7.2%), and Pd97W3/C bimetallene (9.5 A mgPd−1, 14.1%). The mechanism by which Pd50W27Nb23/C enhances the EOR performance is evaluated by in situ Fourier transform infrared spectroscopy and density functional theory calculations. It is found that W and Nb enhance the adsorption of CH3CH2OH and oxophilic high‐valence Nb accelerates the subsequent oxidation of CO and CHx species. Moreover, Nb promotes the cleavage of CC bonds and increases the C1 selectivity. Pd60W28Mo12/C and Pd64W27Ta9/C trimetallene synthesized by the same method also exhibit excellent EOR performance. [ABSTRACT FROM AUTHOR]

We have investigated computationally the effect of π-conjugated extension on the charge transfer properties of triphenylene and coronene; where we have added fused benzene or triazole rings in the parent molecule. The results showed that the six polycyclic aromatic hydrocarbons investigated are semiconductor molecules. The μ- values of molecules naphthotriphenylene (a1), tribenzocoronene (b1), and tristriazolecoronene (b2) were 1.5 to 21.5 times that of the corresponding μ+ values, suggesting that they are n-type organic semiconductors. Compared with the results obtained by the B3LYP and B3LYP + D3 methods, the charge transport mobility obtained using M06-2X, M06-2X + D3, and M08-HX showed the similar calculation results. [ABSTRACT FROM AUTHOR]

Charge transport rate is one of the key parameters determining the performance of organic electronic devices. Based on density functional theory, exchange-correlation functionals which adequately account for non-covalent interactions, such as M06-2X and wB97XD, should significantly improve the accuracy of charge transport rate calculations for large systems with non-covalent interactions. In this work, the B3LYP hybrid functional, the variant hybrid functional M06-2X, and the long-range-corrected wB97XD functional were used to perform geometry optimizations and charge transport rate calculations on 11 variants of tetrabenzo[ a,d,j,m ]coronene, including tetrabenzo[ a,d,j,m ]coronene itself and its tetra-substituted and octa-substituted derivatives. Our results indicate that the molecular geometries of these benzocoronene semiconductors are large quasi-planar conjugated π systems, and the incorporation of different substituents significantly affects their frontier molecular orbitals. The hole carrier mobility (µ +) and electron carrier mobility (µ −) of the methoxy-substituted derivatives (TBC(OCH3)4 and TBC(OCH3)8) were relatively low. The results of the tetrabenzo[ a,d,j,m ]coronene molecules studied were consistent with using the aforementioned M06-2X, wB97XD, and B3LYP methods. We found that the octa-substituted derivatives (TBCF8, TBCCl8, TBC(CH3)8, and TBC(CN)8) could be used as p-type organic semiconductor materials. [ABSTRACT FROM AUTHOR]

The charge transfer rate of seven non-peripherally phthalocyanine–tetrabenzoporphyrin hybrids was investigated theoretically at the level of B3LYP/6-31+G(d,p) using density functional theory. The results showed that the hybrids are semiconductor molecules, which have a certain absorption in the visible region. The hole or electron transport capability of a non-peripherally substituted octamethyl phthalocyanine molecule is obviously better than that of phthalocyanine or non-peripherally substituted octafluorine, octamethoxy phthalocyanine molecules at 300 K, whereas the holes or electron transport capabilities of four non-peripherally substituted octamethoxy phthalocyanine–tetrabenzoporphyrin hybrids are basically the same. Overall, the hole transport capability of hybrids is superior to their electron transport capability. The charge transfer rate constant and the carrier mobility rate of three representative molecules using three methods, that is the long range-corrected functionals CHB-B3LYP and WB97XD, the metahybrid GGA M06-2X functional, are consistent with the use of the density functional B3LYP method. [ABSTRACT FROM PUBLISHER]