This paper investigates the fundamental data detection problem with burst interference in massive multiple-input multiple-output orthogonal frequency division multiplexing(MIMO-OFDM) systems. In particular, burst inte...This paper investigates the fundamental data detection problem with burst interference in massive multiple-input multiple-output orthogonal frequency division multiplexing(MIMO-OFDM) systems. In particular, burst interference may occur only on data symbols but not on pilot symbols, which means that interference information cannot be premeasured. To cancel the burst interference, we first revisit the uplink multi-user system and develop a matrixform system model, where the covariance pattern and the low-rank property of the interference matrix is discussed. Then, we propose a turbo message passing based burst interference cancellation(TMP-BIC) algorithm to solve the data detection problem, where the constellation information of target data is fully exploited to refine its estimate. Furthermore, in the TMP-BIC algorithm, we design one module to cope with the interference matrix by exploiting its lowrank property. Numerical results demonstrate that the proposed algorithm can effectively mitigate the adverse effects of burst interference and approach the interference-free bound.展开更多
As a two-dimensional(2D) material, polymeric carbon nitride(g-C_3N_4) nanosheet holds great potentials in environmental purification and solar energy conversion. In this review, we summarized latest progress in the op...As a two-dimensional(2D) material, polymeric carbon nitride(g-C_3N_4) nanosheet holds great potentials in environmental purification and solar energy conversion. In this review, we summarized latest progress in the optimization of photocatalytic performance in 2D g-C_3N_4. Some of the latest structural engineering methods were summed up, where the relevant influences on the behaviors of photoinduced species were emphasized. Furthermore, the construction strategies for band structure modulation and charge separation promotion were then discussed in detail. A brief discussion on the opportunity and challenge of 2D g-C_3N_4-based photocatalysis are presented as the conclusion of this review.展开更多
Fabrication of well-designed heterojunctions is an extraordinarily attractive pathway for boosting the photocatalytic activity toward CO_(2) photoreduction.Herein,a novel kind of na nosheet-based intercalation hybrid ...Fabrication of well-designed heterojunctions is an extraordinarily attractive pathway for boosting the photocatalytic activity toward CO_(2) photoreduction.Herein,a novel kind of na nosheet-based intercalation hybrid coupled with CdSe quantum dots(QDs) was successfully fabricated by a facile solvothermal method and served as photocatalyst for full-spectrum-light-driven CO_(2) reduction.Ultra-small CdSe QDs were rationally in-situ introduced and coupled with lamellar ZnSe-intercalation hybrid nanosheet,resulting in the formation of CdSe Q.Ds/ZnSe hybrid heterojunction.Significantly,the concentration of Cd^(2+) could change directly the crystallinity and micromorphology of ZnSe intercalation hybrid,which in turn would impact on the photocatalysis activity.The optimized CdSe QDs/ZnSe hybrid-5 composite demonstrated a considerable CO yield rate of the 25.6 μmol g^(-1) h^(-1) without any additional cocatalysts or sacrificial agents assisting,making it one of the best reported performance toward CO_(2) photoreduction under full-spectrum light.The elevated CO_(2) photoreduction activity could be attributed to the special surface heterojunction,leading to improving the ability of light absorption and promoting the separation/transfer of photogenerated carriers.This present study developed a new strategy for designing inorganic-organic heterojunctions with enhanced photocatalyst for CO_(2) photoreduction and provided an available way to simultaneously mitigate the greenhouse effect and alleviate energy shortage pressure.展开更多
The electrocatalytic reduction of CO_(2)to HCOOH(ERC-HCOOH)is one of the most feasible ways to alleviate energy crisis and solve environmental problems.Nevertheless,it remains a challenge for ERC-HCOOH to maintain exc...The electrocatalytic reduction of CO_(2)to HCOOH(ERC-HCOOH)is one of the most feasible ways to alleviate energy crisis and solve environmental problems.Nevertheless,it remains a challenge for ERC-HCOOH to maintain excellent activity and selectivity in a wide potential window.Herein,ultra-thin flower-like Bi_(2)O_(2)CO_(3)nanosheets(NSs)with abundant Bi-O structures were in situ synthesized on carbon paper via topological transformation and post-processing.Faraday efficiency of HCOOH(FEHCOOH)reached 90%in a wide potential window(-1.5 to-1.8 V vs.Ag/AgCl).Significantly,excellent FEHCOOH(90%)and current density(47 mA·cm^(-2))were achieved at-1.8 V vs.Ag/AgCl.The X-ray absorption fine structure(XAFS)combined with density functional theory(DFT)calculation demonstrated that the excellent performance of Bi_(2)O_(2)CO_(3)NS was attributed to the abundant Bi-O structures,which was conducive to enhancing the adsorption of CO_(2)^(*)and OCHO^(*)intermediates and can effectively inhibit hydrogen evolution.The excellent performance of Bi_(2)O_(2)CO_(3)NS over a wide potential window could provide new insights for the efficient electrocatalytic conversion of CO_(2).展开更多
基金supported by the National Key Laboratory of Wireless Communications Foundation,China (IFN20230204)。
文摘This paper investigates the fundamental data detection problem with burst interference in massive multiple-input multiple-output orthogonal frequency division multiplexing(MIMO-OFDM) systems. In particular, burst interference may occur only on data symbols but not on pilot symbols, which means that interference information cannot be premeasured. To cancel the burst interference, we first revisit the uplink multi-user system and develop a matrixform system model, where the covariance pattern and the low-rank property of the interference matrix is discussed. Then, we propose a turbo message passing based burst interference cancellation(TMP-BIC) algorithm to solve the data detection problem, where the constellation information of target data is fully exploited to refine its estimate. Furthermore, in the TMP-BIC algorithm, we design one module to cope with the interference matrix by exploiting its lowrank property. Numerical results demonstrate that the proposed algorithm can effectively mitigate the adverse effects of burst interference and approach the interference-free bound.
基金supported by the National Natural Science Foundation of China (21437003, 21673126, 21621003, 21761142017)the Youth Innovation Promotion Association of CAS (2017493)Young Elite Scientist Sponsorship Program by CAST and Collaborative Innovation Center for Regional Environmental Quality
文摘As a two-dimensional(2D) material, polymeric carbon nitride(g-C_3N_4) nanosheet holds great potentials in environmental purification and solar energy conversion. In this review, we summarized latest progress in the optimization of photocatalytic performance in 2D g-C_3N_4. Some of the latest structural engineering methods were summed up, where the relevant influences on the behaviors of photoinduced species were emphasized. Furthermore, the construction strategies for band structure modulation and charge separation promotion were then discussed in detail. A brief discussion on the opportunity and challenge of 2D g-C_3N_4-based photocatalysis are presented as the conclusion of this review.
基金supported by the National Natural Science Foundation of China (Nos.51902266 and 22002185)the Fundamental Research Funds for the Central Universities (Nos.310201QD0410 and 3102019ZD0403)+2 种基金the Natural Science Foundation of Beijing (No.2204100)Natural Science Foundation of Shaanxi (No.2020JQ-143)supported by the Research Fund of the State Key Laboratory of Solidification Processing (NPU),China (No.2019-TS-12)。
文摘Fabrication of well-designed heterojunctions is an extraordinarily attractive pathway for boosting the photocatalytic activity toward CO_(2) photoreduction.Herein,a novel kind of na nosheet-based intercalation hybrid coupled with CdSe quantum dots(QDs) was successfully fabricated by a facile solvothermal method and served as photocatalyst for full-spectrum-light-driven CO_(2) reduction.Ultra-small CdSe QDs were rationally in-situ introduced and coupled with lamellar ZnSe-intercalation hybrid nanosheet,resulting in the formation of CdSe Q.Ds/ZnSe hybrid heterojunction.Significantly,the concentration of Cd^(2+) could change directly the crystallinity and micromorphology of ZnSe intercalation hybrid,which in turn would impact on the photocatalysis activity.The optimized CdSe QDs/ZnSe hybrid-5 composite demonstrated a considerable CO yield rate of the 25.6 μmol g^(-1) h^(-1) without any additional cocatalysts or sacrificial agents assisting,making it one of the best reported performance toward CO_(2) photoreduction under full-spectrum light.The elevated CO_(2) photoreduction activity could be attributed to the special surface heterojunction,leading to improving the ability of light absorption and promoting the separation/transfer of photogenerated carriers.This present study developed a new strategy for designing inorganic-organic heterojunctions with enhanced photocatalyst for CO_(2) photoreduction and provided an available way to simultaneously mitigate the greenhouse effect and alleviate energy shortage pressure.
基金This work was supported by the National Natural Science Foundation of China(Nos.22002185 and 21701168)Beijing Natural Science Foundation(No.2204100)+2 种基金the National Key Research and Development Program of China(Nos.2020YFA0710304 and 2020YFA0406101)Civil Aerospace Technology Research Project(No.B0108),Dalian high level talent innovation project(No.2019RQ063)Open project Foundation of State Key Laboratory of Structural Chemistry,Fujian Institute of Research on the Structure of Matter,Chinese Academy of Sciences(No.20200021).
文摘The electrocatalytic reduction of CO_(2)to HCOOH(ERC-HCOOH)is one of the most feasible ways to alleviate energy crisis and solve environmental problems.Nevertheless,it remains a challenge for ERC-HCOOH to maintain excellent activity and selectivity in a wide potential window.Herein,ultra-thin flower-like Bi_(2)O_(2)CO_(3)nanosheets(NSs)with abundant Bi-O structures were in situ synthesized on carbon paper via topological transformation and post-processing.Faraday efficiency of HCOOH(FEHCOOH)reached 90%in a wide potential window(-1.5 to-1.8 V vs.Ag/AgCl).Significantly,excellent FEHCOOH(90%)and current density(47 mA·cm^(-2))were achieved at-1.8 V vs.Ag/AgCl.The X-ray absorption fine structure(XAFS)combined with density functional theory(DFT)calculation demonstrated that the excellent performance of Bi_(2)O_(2)CO_(3)NS was attributed to the abundant Bi-O structures,which was conducive to enhancing the adsorption of CO_(2)^(*)and OCHO^(*)intermediates and can effectively inhibit hydrogen evolution.The excellent performance of Bi_(2)O_(2)CO_(3)NS over a wide potential window could provide new insights for the efficient electrocatalytic conversion of CO_(2).
