Carbon electrocatalyst materials based on lignocellulosic biomass with multi-components,various dimensions,high carbon content,and hierarchical morphology structures have gained great popularity in electrocatalytic ap...Carbon electrocatalyst materials based on lignocellulosic biomass with multi-components,various dimensions,high carbon content,and hierarchical morphology structures have gained great popularity in electrocatalytic applications recently.Due to the catalytic deficiency of neutral carbon atoms,the usage of single lignocellulosic-based carbon materials in electrocatalysis involving energy storage and conversion presents unsatisfactory applicability.However,atomic-level modulation of lignocellulose-based carbon materials can optimize the electronic structures,charge separation,transfer processes,and so forth,which results in substantially enhanced electrocatalytic performance of carbon-based catalysts.This paper reviews the recent advances in the rational design of lignocellulosic-based carbon materials as electrocatalysts from an atomic-level perspective,such as self/external heteroatom doping and metal modification.Then,through systematic discussion of the design principles and reaction mechanisms of the catalysts,the applications of the prepared lignocellulosic-based catalysts in rechargeable batteries and electrocatalysis are reviewed.Finally,the challenges in improving the catalytic performance of lignocellulosic-based carbon materials as electrocatalysts and the prospects in diverse applications are reviewed.This review contributes to the synthesis strategy of lignocellulose-based carbon electrocatalysts via atomic-level modulation,which in turn promotes the lignocellulose valorization for energy storage and conversion.展开更多
We theoretically investigate the phenomena of electromagnetically induced grating in an M-type five-level atomic system. It is found that a weak field can be effectively diffracted into high-order directions using a s...We theoretically investigate the phenomena of electromagnetically induced grating in an M-type five-level atomic system. It is found that a weak field can be effectively diffracted into high-order directions using a standing wave coupling field, and different depths of the phase modulation can disperse the diffraction light into different orders. When the phase modulation depth is approximated to the orders of π, 2π and 3π, the first-, second- and third-order diffraction intensity reach the maximum, respectively. Thus we can take advantage of the phase modulation to control the probe light dispersing into the required high orders.展开更多
Exploring efficient transition-metal-based electrocatalysts is critical for the wide application of electrochemical hydrogen generation technology.Although the phase displays prominent influence on their performance,i...Exploring efficient transition-metal-based electrocatalysts is critical for the wide application of electrochemical hydrogen generation technology.Although the phase displays prominent influence on their performance,it remains a major challenge to achieve phase regulation in the same synthesis method and elucidate the intrinsic relationship between the phase and activity.Herein,we developed a sulfur induced electrodeposition strategy to achieve the precise phase regulation of nickel-based materials from Ni(OH)_(2)to Ni and Ni_(3)S_(2).S atoms can be introduced into Ni and Ni(OH)_(2)due to sulfur inducement,and the S proportion is finely controlled via changing the deposition parameters.Importantly,the obtained S-Ni catalyst displays enhanced hydrogen evolution activity with an ultralow overpotential of 27 mV at 10 mA cm^(-2),which is superior to the S-Ni(OH)_(2),Ni_(3)S_(2),and even Pt/C.Density functional theory(DFT)calculations disclose the S-Ni catalyst exhibits optimal charge state and local coordination,remarkably optimizing the water adsorption and Ni-H^(*)binding energy.This work provides new insights into phase regulation in electrodeposition and an understanding of the intrinsic relationship between phase and activity.展开更多
Bismuth tungstate(Bi_(2)WO_(6))has become a research hotspot due to its potential in photocatalytic energy conversion and environmental purification.Nevertheless,the limited light absorption and fast recombination of ...Bismuth tungstate(Bi_(2)WO_(6))has become a research hotspot due to its potential in photocatalytic energy conversion and environmental purification.Nevertheless,the limited light absorption and fast recombination of photogenerated carriers hinder the further improvement of the photocatalytic performance of Bi_(2)WO_(6).Herein,we provide a systematic review for the recent advances on Bi_(2)WO_(6)‐based photocatalysts.It starts with the crystal structure,optical properties and photocatalytic fundamentals of Bi_(2)WO_(6).Then,we focus on the modification strategies of Bi_(2)WO_(6)based on morphology control,atomic modulation and composite fabrication for diverse photocatalytic applications,such as organic synthesis,water splitting,CO2 reduction,water treatment,air purification,bacterial inactivation,etc.Finally,some current challenges and future development prospects are proposed.We expect that this review can provide a useful reference and guidance for the development of efficient Bi_(2)WO_(6)photocatalysts.展开更多
A simple and robust technique is reported to offset lock a single semiconductor laser to the atom resonance line with a frequency difference easily adjustable from a few tens of megahertz up to tens of gigahertz. The ...A simple and robust technique is reported to offset lock a single semiconductor laser to the atom resonance line with a frequency difference easily adjustable from a few tens of megahertz up to tens of gigahertz. The proposed scheme makes use of the frequency modulation spectroscopy by modulating sidebands of a fiber electro-optic modulator output. The short-term performances of a frequency offset locked semiconductor laser are experimentally demonstrated with the Allan variance of around 3.9 × 10-11 at a 2 s integration time. This method may have many applications, such as in Raman optics for an atom interferometer.展开更多
基金supported by the National Natural Science Foundation of China(32071721,32071720,32271814,32301530,32471806)Tianjin Excellent Special Commissioner for Agricultural Science and Technology Project(23ZYCGSN00580)+4 种基金Young Elite Scientist Sponsorship Program by Cast(No.YESS20230242)Natural Science Foundation of Tianjin(23JCZDJC00630)the China Postdoctoral Science Foundation under Grant Number(2023M741363,2023M740563)the Postdoctoral Innovation Project of Shandong Province(SDCX-ZG-202302031)China Scholarship Council(No.202408120091,No.202408120105).
文摘Carbon electrocatalyst materials based on lignocellulosic biomass with multi-components,various dimensions,high carbon content,and hierarchical morphology structures have gained great popularity in electrocatalytic applications recently.Due to the catalytic deficiency of neutral carbon atoms,the usage of single lignocellulosic-based carbon materials in electrocatalysis involving energy storage and conversion presents unsatisfactory applicability.However,atomic-level modulation of lignocellulose-based carbon materials can optimize the electronic structures,charge separation,transfer processes,and so forth,which results in substantially enhanced electrocatalytic performance of carbon-based catalysts.This paper reviews the recent advances in the rational design of lignocellulosic-based carbon materials as electrocatalysts from an atomic-level perspective,such as self/external heteroatom doping and metal modification.Then,through systematic discussion of the design principles and reaction mechanisms of the catalysts,the applications of the prepared lignocellulosic-based catalysts in rechargeable batteries and electrocatalysis are reviewed.Finally,the challenges in improving the catalytic performance of lignocellulosic-based carbon materials as electrocatalysts and the prospects in diverse applications are reviewed.This review contributes to the synthesis strategy of lignocellulose-based carbon electrocatalysts via atomic-level modulation,which in turn promotes the lignocellulose valorization for energy storage and conversion.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11274112 and 11474092the Key Project of Shanghai Municipal Education Commission under Grant No 14ZZ056+1 种基金the Shanghai Natural Science Fund Project under Grant No14ZR1410300the Key Research Project of Henan Province Education Department under Grant No 13A140818
文摘We theoretically investigate the phenomena of electromagnetically induced grating in an M-type five-level atomic system. It is found that a weak field can be effectively diffracted into high-order directions using a standing wave coupling field, and different depths of the phase modulation can disperse the diffraction light into different orders. When the phase modulation depth is approximated to the orders of π, 2π and 3π, the first-, second- and third-order diffraction intensity reach the maximum, respectively. Thus we can take advantage of the phase modulation to control the probe light dispersing into the required high orders.
基金supported by the National Natural Science Foundation of China(52271210,22179032,52171176)。
文摘Exploring efficient transition-metal-based electrocatalysts is critical for the wide application of electrochemical hydrogen generation technology.Although the phase displays prominent influence on their performance,it remains a major challenge to achieve phase regulation in the same synthesis method and elucidate the intrinsic relationship between the phase and activity.Herein,we developed a sulfur induced electrodeposition strategy to achieve the precise phase regulation of nickel-based materials from Ni(OH)_(2)to Ni and Ni_(3)S_(2).S atoms can be introduced into Ni and Ni(OH)_(2)due to sulfur inducement,and the S proportion is finely controlled via changing the deposition parameters.Importantly,the obtained S-Ni catalyst displays enhanced hydrogen evolution activity with an ultralow overpotential of 27 mV at 10 mA cm^(-2),which is superior to the S-Ni(OH)_(2),Ni_(3)S_(2),and even Pt/C.Density functional theory(DFT)calculations disclose the S-Ni catalyst exhibits optimal charge state and local coordination,remarkably optimizing the water adsorption and Ni-H^(*)binding energy.This work provides new insights into phase regulation in electrodeposition and an understanding of the intrinsic relationship between phase and activity.
文摘Bismuth tungstate(Bi_(2)WO_(6))has become a research hotspot due to its potential in photocatalytic energy conversion and environmental purification.Nevertheless,the limited light absorption and fast recombination of photogenerated carriers hinder the further improvement of the photocatalytic performance of Bi_(2)WO_(6).Herein,we provide a systematic review for the recent advances on Bi_(2)WO_(6)‐based photocatalysts.It starts with the crystal structure,optical properties and photocatalytic fundamentals of Bi_(2)WO_(6).Then,we focus on the modification strategies of Bi_(2)WO_(6)based on morphology control,atomic modulation and composite fabrication for diverse photocatalytic applications,such as organic synthesis,water splitting,CO2 reduction,water treatment,air purification,bacterial inactivation,etc.Finally,some current challenges and future development prospects are proposed.We expect that this review can provide a useful reference and guidance for the development of efficient Bi_(2)WO_(6)photocatalysts.
基金supported by the National Natural Science Foundation of China(No.61473166)
文摘A simple and robust technique is reported to offset lock a single semiconductor laser to the atom resonance line with a frequency difference easily adjustable from a few tens of megahertz up to tens of gigahertz. The proposed scheme makes use of the frequency modulation spectroscopy by modulating sidebands of a fiber electro-optic modulator output. The short-term performances of a frequency offset locked semiconductor laser are experimentally demonstrated with the Allan variance of around 3.9 × 10-11 at a 2 s integration time. This method may have many applications, such as in Raman optics for an atom interferometer.
