The photocatalytic nitrogen reduction reaction(NRR)is a sustainable green alternative to the Haber-Bosch process for ammonia production.However,due to the inert properties of dinitrogen,the photocatalytic activity in ...The photocatalytic nitrogen reduction reaction(NRR)is a sustainable green alternative to the Haber-Bosch process for ammonia production.However,due to the inert properties of dinitrogen,the photocatalytic activity in N2 reduction is still pretty low.Based on density functional theory calculations,this study finds that the formation energy of oxygen vacancies around the V site in InVO_(4)was significantly lower than that around the In site.This indicated that the V-O bond was thermodynamically less stable and tends to break preferentially.Therefore,selective cleavage of the V-O bond was achieved by subjecting InVO_(4)to transient high-temperature treatment via rapid Joule heating technology.This resulted in the directed construction of an InVO_(4)-JH catalyst enriched with oxygen vacancies and exposing coordination-unsaturated V sites.The resulting InVO_(4)-JH catalyst delivered a photocatalytic ammonia production rate of up to 35.28μmol g^(-1)h^(-1)under ambient conditions without any sacrificial agent,while exhibiting excellent stability and reaction selectivity.Mechanistic studies and structural characterization confirmed that the formation of oxygen vacancies via V-O bond cleavage releases electrons,which reduce adjacent V5+to V4+.This created localized electron-rich regions at exposed V sites.Theoretical calculations further confirmed that these exposed V sites act as the active centers of the reaction,not only significantly enhancing nitrogen adsorption but also substantially lowering the energy barrier of the hydrogenation step through alternative reaction pathways.This work provides a novel strategy for the rational design of highly efficient defect-engineered catalysts via targeted bond cleavage.展开更多
Traditional algorithms do not fully utilize the timing information of non-cooperative targets,and setting too many motion parameters can lead to complex dynamic model calculations.This paper proposes a long short-term...Traditional algorithms do not fully utilize the timing information of non-cooperative targets,and setting too many motion parameters can lead to complex dynamic model calculations.This paper proposes a long short-term memory(LSTM)network-based method for estimating the parameters of the active segment of the non-cooperative target under single-satellite observation.Based on the simulation training set of the active segment of the non-cooperative target,the network parameters of the LSTM network are designed,the motion characteristics of the active segment of the non-cooperative target are fully excavated through data-driven methods,and the candidate cutting trajectories are screened and predicted to realize the estimation of the motion parameters of the active segment of the non-cooperative target under the condition of single-satellite observation.The experimental results show that the estimation method proposed in this paper can effectively deal with the inaccurate problem with the non-cooperative target’s active segment motion model established under the condition of single-satellite observation,obtain more accurate active segment motion parameters,and provide a feasible new idea and method for the parameter estimation of the active segment of the non-cooperative target under the single-satellite observation.展开更多
基金the National Natural Science Foundation of China(grant no.:22408356)the Shandong Provincial Natural Science Foundation(grant no.:ZR2024MB052)+1 种基金the Postdoctoral Fellowship Program of CPSF(grant no.:GZC20250790)the Qingdao Natural Science Foundation(grant no.:24-4-4-zrjj-195-jch).
文摘The photocatalytic nitrogen reduction reaction(NRR)is a sustainable green alternative to the Haber-Bosch process for ammonia production.However,due to the inert properties of dinitrogen,the photocatalytic activity in N2 reduction is still pretty low.Based on density functional theory calculations,this study finds that the formation energy of oxygen vacancies around the V site in InVO_(4)was significantly lower than that around the In site.This indicated that the V-O bond was thermodynamically less stable and tends to break preferentially.Therefore,selective cleavage of the V-O bond was achieved by subjecting InVO_(4)to transient high-temperature treatment via rapid Joule heating technology.This resulted in the directed construction of an InVO_(4)-JH catalyst enriched with oxygen vacancies and exposing coordination-unsaturated V sites.The resulting InVO_(4)-JH catalyst delivered a photocatalytic ammonia production rate of up to 35.28μmol g^(-1)h^(-1)under ambient conditions without any sacrificial agent,while exhibiting excellent stability and reaction selectivity.Mechanistic studies and structural characterization confirmed that the formation of oxygen vacancies via V-O bond cleavage releases electrons,which reduce adjacent V5+to V4+.This created localized electron-rich regions at exposed V sites.Theoretical calculations further confirmed that these exposed V sites act as the active centers of the reaction,not only significantly enhancing nitrogen adsorption but also substantially lowering the energy barrier of the hydrogenation step through alternative reaction pathways.This work provides a novel strategy for the rational design of highly efficient defect-engineered catalysts via targeted bond cleavage.
基金supported by the National Natural Science Foundation of China under grant 42271448by the Key Laboratory of Land satellite Remote sensing Application,Ministry of Natural Resources of the People’s Republic of China(Grant No.KLSMNR-G202317).
文摘Traditional algorithms do not fully utilize the timing information of non-cooperative targets,and setting too many motion parameters can lead to complex dynamic model calculations.This paper proposes a long short-term memory(LSTM)network-based method for estimating the parameters of the active segment of the non-cooperative target under single-satellite observation.Based on the simulation training set of the active segment of the non-cooperative target,the network parameters of the LSTM network are designed,the motion characteristics of the active segment of the non-cooperative target are fully excavated through data-driven methods,and the candidate cutting trajectories are screened and predicted to realize the estimation of the motion parameters of the active segment of the non-cooperative target under the condition of single-satellite observation.The experimental results show that the estimation method proposed in this paper can effectively deal with the inaccurate problem with the non-cooperative target’s active segment motion model established under the condition of single-satellite observation,obtain more accurate active segment motion parameters,and provide a feasible new idea and method for the parameter estimation of the active segment of the non-cooperative target under the single-satellite observation.
