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| 1 | Theoretical insight into methanol steam reforming on indium oxide with different coordination environments显示文摘Indium oxide(In_2O_3) has demonstrated to be an effective non-noble metal catalyst for methanol steam reforming reaction(MSR).However, the reaction mechanism of MSR and crucial structure-activity relations determining the catalytic performance of In_2O_3 are still not fully understood yet. Using density functional theory(DFT) calculation, we systematically investigate the MSR process over a high-index In_2O_3(211) and a favoured catalytic cycle of MSR is determined. The results show that In_2O_3(211) possesses excellent dehydrogenation and oxidizing ability, on which CH_3 OH can readily adsorb on the In4 c site and be easily activated by the reactive lattice oxygens, resulting in a total oxidation into CO_2 rather than CO, while the H_2 formation through surface H–H coupling limits the overall MSR activity because of the strong H adsorption on the two-coordinated lattice O(O_(2c)). Our analyses show that the relatively inert three-coordinated lattice O(O_(3c)) could play an important catalytic role. To uncover the influence of the local coordination of surface In atoms and lattice O on the catalytic activity, we evaluate the activity trend of several types of In_2O_3 surfaces including(211),(111), and(100) by examining the rate-limiting, which reveals the following activity order:(211)>(111)>(100). These findings provide an in-depth understanding on the MSR reaction mechanism over In_2O_3 catalysts and some basic structure-activity relations at the atomic scale, could facilitate the rational design of In_2O_3-based catalysts for MSR by controlling the local coordination environment of surface active sites. | Jinglin Wang Haifeng Wang P.Hu | 2018 | Science China Chemistry2018，61，3： | 2 |
| 2 | Identification of the active sites and mechanism for partial methane oxidation to methanol over copper-exchanged CHA zeolites显示文摘To make methane a suitable energy carrier and transport less costly,it is an urgent and challenging task for us to convert methane to liquid under mild conditions efficiently.In this study,we explored partial methane oxidation to methanol by density functional theory(DFT)calculations using a hybrid functional(HSE06)with van der Waals(vdW)interactions.The stabilities of different active sites over SSZ-13 and SAPO-34,two CHA type zeolites,are thoroughly investigated by ab initio molecular dynamics(AIMD)simulations and ab initio thermodynamics analyses.Four possible active sites,namely[CuOHCu]2+,[Cu(OH)2Cu]2+,[CuOCu]2+and[CuOH]+,are identified stable.Methane-to-methanol reaction mechanisms are further studied upon these most stable active sites,among which[CuOCu]2+and[CuOH]+are proved to be reactive.The migration of species among zeolite pores are also discussed,which accounts for the activity on[CuOH]+sites.This concept may represent a more complete picture of catalytic reactions over zeolites in general. | Yu Mao P.Hu | 2020 | Science China Chemistry2020，63，6： | 2 |
| 3 | Preface显示文摘Science generally proceeds based on a mutual interaction between theory and experiment:theory can explain experimental phenomena and propose general rules for the design of new experiments while experiment can verify theoretical predictions and discover new phenomena to improve theories.Yet,the progress of heterogeneous catalysis mainly relied on experimental advances for a long time.In its early days,heterogeneous catalysis was an empirically applied field,in which the tests of reactivity and selectivity for syn- | P.Hu Zhipan Liu | 2015 | Science China Chemistry2015，58，4： | 1 |
| 4 | Theoretical and experimental study of surface tension and dynamic surface tension of aqueous lithium bromide and water with additive显示文摘 | W.L.Cheng Z.S.Chen A.Akisawa P.Hu T.Kashiwagi | | 0，，02： | 1 |
| 5 | Design and synthesis of simpliifed taxol analogs based on the T-Taxol bioactive conformation显示文摘 | Zhao Jielu Bane Susan Snyder James P.Hu Haipeng Mukherjee K amalika Slebodnick Carla Kingston David G.I | | 0，，24： | 1 |
| 6 | Insights into the selective catalytic reduction of NO by NH_3 over Mn_3O_4(110):a DFT study coupled with microkinetic analysis显示文摘Nitric oxide(NO_x), as one of the main pollutants, can contribute to a series of environmental problems, and to date the selective catalytic reduction(SCR) of NO_x with NH_3 in the presence of excess of O_2 over the catalysts has served as one of the most effective methods, in which Mn-based catalysts have been widely studied owing to their excellent low-temperature activity toward NH3-SCR. However, the related structure-activity relation was not satisfactorily explored at the atomic level. By virtue of DFT+U calculations together with microkinetic analysis, we systemically investigate the selective catalytic reduction process of NO with NH_3 over Mn_3 O_4(110), and identify the crucial thermodynamic and kinetic factors that limit the catalytic activity and selectivity.It is found that NH3 prefers to adsorb on the Lewis acid site and then dehydrogenates into NH_2~* assisted by either the two-or three-fold lattice oxygen; NH_2~* would then react with the gaseous NO to form an important intermediate NH_2 NO that prefers to convert into N_2 O rather than N_2 after the sequential dehydrogenation, while the residual H atoms interact with O_2 and left the surface in the form of H_2 O. The rate-determining step is proposed to be the coupling reaction between NH_2~* and gaseous NO.Regarding the complex surface structure of Mn_3 O_4(110),the main active sites are quantitatively revealed to be O_(3 c) and Mn_(4 c). | Mingxia Yang Haiyang Yuan Haifeng Wang P.Hu | 2018 | Science China Chemistry2018，61，4： | 1 |
| 7 | Machine Learning for Chemistry:Basics and Applications显示文摘The past decade has seen a sharp increase in machine learning(ML)applications in scientific research.This review introduces the basic constituents of ML,including databases,features,and algorithms,and highlights a few important achievements in chemistry that have been aided by ML techniques.The described databases include some of the most popular chemical databases for molecules and materials obtained from either experiments or computational calculations.Important two-dimensional(2D)and three-dimensional(3D)features representing the chemical environment of molecules and solids are briefly introduced.Decision tree and deep learning neural network algorithms are overviewed to emphasize their frameworks and typical application scenarios.Three important fields of ML in chemistry are discussed:(1)retrosynthesis,in which ML predicts the likely routes of organic synthesis;(2)atomic simulations,which utilize the ML potential to accelerate potential energy surface sampling;and(3)heterogeneous catalysis,in which ML assists in various aspects of catalytic design,ranging from synthetic condition optimization to reaction mechanism exploration.Finally,a prospect on future ML applications is provided. | Yun-Fei Shi Zheng-Xin Yang Sicong Ma Pei-Lin Kang Cheng Shang P.Hu Zhi-Pan Liu | 2023 | Engineering2023，，8： | 0 |
| 8 | Theoretical insight into the selectivities of copper-catalyzing heterogeneous reduction of carbon dioxide显示文摘The chemical reduction of carbon dioxide(CO2) has always drawn intensive attentions as it can not only remove CO2 which is the primary greenhouse gas but also produce useful fuels. Industrial synthesis of methanol utilizing copper-based catalysts is a commonly used process for CO2 hydrogenation. Despite extensive efforts on improving its reaction mechanism by identifying the active sites and optimizing the operating temperature and pressure, it is still remains completely unveiled. The selectivities of CO2 electroreduction at copper electrode could mainly be towards carbon monoxide(CO), formic acid(HCOOH), methane(CH4) or ethylene(C2H4), which depends on the chemical potentials of hydrogen controlled by the applied potential. Interestingly, methanol could hardly be produced electrochemically despite utilizing metallic copper as catalysts in both processes. Moreover, the mechanistic researches have also been performed aiming to achieve the higher selectivity towards more desirable higher hydrocarbons. In this work, we review the present proposals of reaction mechanisms of copper catalyzing CO2 reduction in industrial methanol synthesis and electrochemical environment in terms of density functional theory(DFT) calculations, respectively. In addition, the influences of the simulation methods of solvation and electrochemical model at liquid-solid interface on the selectivity are discussed and compared. | Xitong Sun Xiaoming Cao P.Hu | 2015 | Science China Chemistry2015，58，4： | 0 |
| 9 | A first-principles microkinetic study on the hydrogenation of carbon dioxide over Cu(211) in the presence of water显示文摘The hydrogenation of carbon dioxide(CO2)is one of important processes to effectively convert and utilize CO2,which is also regarded as the key step at the industrial methanol synthesis.Water is likely to play an important role in this process,but it still remains elusive.To systematically understand its influence,here we computationally compare the reaction mechanisms of CO2 hydrogenation over the stepped Cu(211)surface between in the absence and presence of water based on microkinetic simulations upon density functional theory(DFT)calculations.The effects of water on each hydrogenation step and the whole activity and selectivity are checked and its physical origin is discussed.It is found that the water could kinetically accelerate the hydrogenation on CO2 to COOH,promoting the reverse water gas shift reaction to produce carbon monoxide(CO).It hardly influences the CO2 hydrogenation to methanol kinetically.In addition,the too high initial partial pressure of water will thermodynamically inhibit the CO2 conversion. | Xitong Sun Peng Wang Zhengjiang Shao Xiaoming Cao P.Hu | 2019 | Science China Chemistry2019，62，12： | 0 |
| 10 | Achieving accuracy and efficiency at the same time: a new kinetic Monte Carlo approach for complicated catalytic systems显示文摘Rational design/screening of more active,more selective,and less expensive catalysts has long been an important target in heterogeneous catalysis [1].In recent decades,the advances of density functional theory (DFT)calculations allow us to theoretically evaluate the activity of catalysts.As shown in Figure 1(a),kinetics serves as the link between the atomic-scale properties obtained by DFT and turnover frequency (TOF)of catalysts. | Yu Mao P.Hu | 2018 | Science China Chemistry2018，61，12： | 0 |
| 11 | Identifying the general trend of activity of non-stoichiometric metal oxide phases for CO oxidation on Pd(111)显示文摘Oxidation state changes under reaction conditions are very common in heterogeneous catalysis. However, due to the limitation of experiment and computational methods, the relation between oxidation state and catalytic activity is not clear. Herein, we obtain the most stable structures of palladium oxide films with different oxidation states on palladium metal surfaces using density functional theory calculations and a state-of-the-art optimization method, namely the particle swarm optimization. These structures clearly show the process of palladium oxide film formation on metallic surfaces. Using CO oxidation as a model reaction, we find that the activities increase first and then decrease with the increase of oxidation states, peaking at Pd_4O_3. Our findings offer an understanding of the phase transformation and the activity of non-stoichiometric phases. | Ziyun Wang P.Hu | 2019 | Science China Chemistry2019，62，6： | 0 |
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