The activation of H_(2)O is a key step of the COS hydrolysis,which may be tuned by oxygen vacancy defects in the catalysts.Herein,we have introduced Cu into Co_(3)O_(4) to regulate the oxygen vacancy defect content of...The activation of H_(2)O is a key step of the COS hydrolysis,which may be tuned by oxygen vacancy defects in the catalysts.Herein,we have introduced Cu into Co_(3)O_(4) to regulate the oxygen vacancy defect content of the catalysts.In situ DRIFTS and XPS spectra reveal that COS and H_(2)O are adsorbed and activated by oxygen vacancy.The 10 at%Cu doped Co_(3)O_(4) sample(10Cu-Co_(3)O_(4))exhibits the optimal activity,100%of COS conversion at 70℃.The improved oxygen vacancies of CueCo_(3)O_(4) accelerate the activation of H_(2)O to form active -OH.COS binds with hydroxyl to form the intermediate HSCO^(-)_(2),and then the activated-OH on the oxygen vacancy reacts with HSCO^(-)_(2) to form HCO^(-)_(3).Meanwhile,the catalyst exhibits high catalytic stability because copper species(Cu+/Cu^(2+))redox cycle mitigate the sulfation of Co_(3)O_(4)(Co^(2+)/Co^(3+)).Our work offers a promising approach for the rational design of cobalt-related catalysts in the highly efficient hydrolysis COS process.展开更多
Electrochemical nitrogen reduction reaction (eNRR) is an alternative promising manner for sustainable N2 fixation with low-emission. The major challenge for developing an efficient electrocatalyst is the cleaving of t...Electrochemical nitrogen reduction reaction (eNRR) is an alternative promising manner for sustainable N2 fixation with low-emission. The major challenge for developing an efficient electrocatalyst is the cleaving of the stable Ntriple bondN triple bonds. Herein, we design a new MoS_(2) with in-plane defect cluster through a bottom-up approach for the first time, where the defect cluster is composed of three adjacent S vacancies. The well-defined in-plane defect clusters could contribute to the strong chemical adsorption and activation towards inert nitrogen, achieving an excellent eNRR performance with an ammonia yield rate of 43.4 ± 3 μg h^(−1) mgcat.^(−1) and a Faradaic efficiency of 16.8 ± 2% at −0.3 V (vs. RHE). The performance is much higher than that of MoS_(2) with the edge defect. Isotopic labeling confirms that N atoms of produced NH4+ originate from N2. Furthermore, the in-plane defect clusters realized the alternate hydrogenation of nitrogen in a side-on way to synthesize ammonia. This work provides a prospecting strategy for fine-tuning in-plane defects in a catalyst, and also promotes the progress of eNRR.展开更多
Developing a suitable catalyst for the elimination of highly toxic carbonyl sulfide(COS)and hydrogen sulfide(H_(2)S) is of great significance in terms of industrial safety and environmental protection.We demonstrate h...Developing a suitable catalyst for the elimination of highly toxic carbonyl sulfide(COS)and hydrogen sulfide(H_(2)S) is of great significance in terms of industrial safety and environmental protection.We demonstrate here the facile synthesis of graphitized 2D micro-meso-macroporous carbons by one-step carbonization of a mixture of urea and glucose at 700–900℃.The as-synthesized graphitized catalysts,designated as 2DNHPC-x(x=urea/glucose mass ratio),are endowed with an ultra-high concentration(12.9–20.2 wt%)of stable and versatile nitrogen sites(e.g.pyrrole and pyridine)which are anchored on the surface via stable covalent bonding.As a result,the 2D-NHPC-x are active in catalytic hydrolysis of COS on pyrrolic N to H_(2)S,and the H_(2)S can be subsequently captured on pyridinic N and converted to elemental sulfur at ambient conditions over the same materials.Among the prepared catalysts,2D-NHPC-x can catalytically hydrolysize 91%of COS to H_(2)S at 30℃,whereas the conversion ratio over the common catalysts g-C_(3)N_(4)and Fe_(2)O_(3)are below 6.0%.Furthermore,these catalysts also exhibit H_(2)S conversion and sulfur selectivity of nearly 100%at 180℃with long-time durability,which is higher than those of the most reported carbonbased catalysts.In contrast,the H_(2)S capacities of activated carbon,ordered mesoporous carbons(OMC)and N-doped OMC are 3.9,1.5 and2.39 mmol g^(-1),respectively.Both the experimental and theoretical results are disclosed that 2D-NHPC-x are superior to the nitrogen-doped porous materials ever applied in simultaneous catalytic elimination of both COS and H_(2)S.展开更多
Electrocatalytic depolymerization of lignin into value-added chemicals offers a promising technique to make biorefining sustainable.Herein,we report a robust trimetallic PdNiBi electrocatalyst for reductive C–O bond ...Electrocatalytic depolymerization of lignin into value-added chemicals offers a promising technique to make biorefining sustainable.Herein,we report a robust trimetallic PdNiBi electrocatalyst for reductive C–O bond cleavage of different lignin model dimers and oxidized lignin under mild conditions.The reduction reaction proceeds with complete substrate conversion and excellent yields toward monomers of phenols(80%–99%)and acetophenones(75%–96%)in the presence of an ionic liquid electrolyte with operational stability.Systematic experimental investigations together with density functional theory(DFT)calculations reveal that the outstanding performance of the catalyst results from the synergistic effect of the metal elements,which facilitates the easier formation of a key Cαradical intermediate and the facile desorption of the as-formed products at the electrode.The results open up new opportunities for lignin valorization through the green electrocatalytic approach.展开更多
Fossil fuels still dominate global energy structure in our modern society,and have led to massive CO_(2) emissions.Recently,ammonia has been regarded as a clean energy carrier toward diminishing or even eliminating th...Fossil fuels still dominate global energy structure in our modern society,and have led to massive CO_(2) emissions.Recently,ammonia has been regarded as a clean energy carrier toward diminishing or even eliminating the CO_(2) emissions and has received significant attention.The ammonia can be synthesized from atmospheric dinitrogen and green hydrogen from water electrolysis by renewable energies,and converted back into dinitrogen and water for energy release,as shown in Figure 1.Benefited from the matured ammonia manufacture and transportation throughout the world for over one century,the already existing high-capacity infrastructure helps efficient storage and redistribution of ammonia with lowest economic cost.However,although considerable progress has been made in this artificial nitrogen cycle,there are still many challenges in developing highly-efficient routes and catalysts.Herein,we evaluate the current catalytic routes of ammonia synthesis(including thermocatalytic synthesis,electrocatalytic synthesis and photocatalytic synthesis)and ammonia utilization(involving ammonia decomposition,direct ammonia fuel cells and ammonia combustion).We also discuss the key issue in each process,and anticipate that our viewpoints and opinions could facilitate the developments of artificial nitrogen cycle and energy decarbonization.展开更多
Being abundant and active,Fe_(2)O_(3) is suitable for selective oxidation of H_(2)S.However,its practical application is limited due to the poor sulfur selectivity and rapid deactivation.Herein,we report a facile temp...Being abundant and active,Fe_(2)O_(3) is suitable for selective oxidation of H_(2)S.However,its practical application is limited due to the poor sulfur selectivity and rapid deactivation.Herein,we report a facile template-free hydrothermal method to fabricate porousα-Fe_(2)O_(3)/SnO_(2) composites with hierarchical nanoflower that can obviously improve the catalytic performance of Fe_(2)O_(3).It was disclosed that the synergistic effect betweenα-Fe_(2)O_(3) and SnO_(2) promotes the physico-chemical properties ofα-Fe_(2)O_(3)/SnO_(2) composites.Specifically,the electron transfer between the Fe^(2+)/Fe^(3+)and Sn^(2+)/Sn^(4+)redox couples enhances the reducibility ofα-Fe_(2)O_(3)/SnO_(2) composites.The number of oxygen vacancies is improved when the Fe cations incorporate into SnO_(2) structure,which facilitates the adsorption and activation of oxygen species.Additionally,the porous structure improves the accessibility of H_(2) S to active sites.Among the composites,Fe1 Sn1 exhibits complete H_(2) S conversion with 100%sulfur selectivity at 220℃,better than those of pureα-Fe_(2)O_(3) and SnO2.Moreover,Fe1 Sn1 catalyst shows high stability and water resistance.展开更多
Ammonia is a key component in fertilizer and the carbon-free hydrogen carrier.Catalytic ammonia synthesis and utilization have played a central role in the development of chemical engineering.The industrial production...Ammonia is a key component in fertilizer and the carbon-free hydrogen carrier.Catalytic ammonia synthesis and utilization have played a central role in the development of chemical engineering.The industrial production of ammonia remains dependent on the energy-and carbon-intensive Haber-Bosch process.A major effort has been devoted to developing robust and efficient catalysts,as well as alternative benign processes.Herein,we detail our endeavors that develop the ammonia synthesis and decomposition catalysts,and utilize the ammonia energy.We firstly discuss the catalysts for ammonia synthesis via dissociative and associative process,and the regulation of catalysts'properties.Then,we review the burgeoning electrocata-lytic nitrogen reduction process,focusing on the enhanced catalytic performances by the regulation of the catalysts and the electrode.Additionally,we provide a novel high-value utilization of ammonia to achieve the"zero-carbon"circular economy.The promising catalysts,reactors,and ammonia energy systems have been discussed in detail.We end this Account that offers future research directions and prospects of ammonia.展开更多
Dye-sensitized photocatalysis has been extensively studied for photocatalytic solar energy conversion due to the advantage in capturing long-wavelength photons with a high absorption coefficient.The rational integrati...Dye-sensitized photocatalysis has been extensively studied for photocatalytic solar energy conversion due to the advantage in capturing long-wavelength photons with a high absorption coefficient.The rational integration of photosensitizer with semiconductor and cocatalyst to collaboratively operate in one system is highly desired.Here,we fabricate a Ni(OH)_(2)-loaded titanate nanosheet(Ni(OH)_(2)/H_(2)Ti_(6)O_(13))composite for high-performance dye-sensitized photocatalytic CO_(2) reduction.The ultrathin H_(2)Ti_(6)O_(13) nanosheets with negative surface charge provide an excellent support to anchor the dye photosensitizer,while the loaded Ni(OH)2 serves as an adsorbent of CO_(2) and electron sink of photoelectrons.As such,the photoelectrons derived from the[Ru(bpy)3]Cl_(2) sensitizer can be targeted transfer to the Ni(OH)_(2) active sites via the H_(2) Ti_(6)O_(13) nanosheets linker.A high CO production rate of 1801μmol g^(-1) h^(-1) is obtained over the optimal Ni(OH)_(2)/H_(2)Ti_(6)O_(13),while the pure H_(2)Ti_(6)O_(13) shows significantly lower CO_(2) reduction performance.The work is anticipated to trigger more research attention on the rational design and synthesis of earth-abundant transition metal-based cocatalysts decorated on ultrathin 2D platforms for artificially photocatalytic CO_(2) reduction.展开更多
Reforestation is an eco-friendly strategy for countering rising carbon dioxide concentrations in the atmosphere and the negative effects of forest loss and degradation.China,with one of the world’s most considerable ...Reforestation is an eco-friendly strategy for countering rising carbon dioxide concentrations in the atmosphere and the negative effects of forest loss and degradation.China,with one of the world’s most considerable afforestation rates,has increased its forest cover from 16.6%20 years ago to 23.0%by 2020.However,the maximum potential forest coverage achieved via tree planting and restoration is uncertain.To map potential tree coverage across China,we developed a random forest regression model relating environmental factors and appropriate forest types.We estimate 67.2 million hectares of land currently available for tree restoration after excluding existing forested areas,urban areas,and agriculture land covers/uses,which is 50%higher than the current understanding.Converting these lands to the forest would generate 3.99 gigatons of new above-and belowground carbon stocks,representing an important contribution to achieving carbon neutrality.This potential is spatially imbalanced,with the largest restorable carbon potential being located in the southwest(29.5%),followed by the northeast(17.2%)and northwest(16.8%).Our study highlights the need to align tree restoration areas with the uneven distribution of carbon sequestration potential.In addition to being a biological mitigation strategy to partially offset carbon dioxide emissions from fossil fuel burning,reforestation should provide other environmental services such as the restoration of degraded soils,conservation of biological diversity,revitalization of hydrological integrity,localized cooling,and improvement in air quality.Because of the collective benefits of forest restoration,we encourage that such activities be ecosystem focused as opposed to solely focusing on tree planting.展开更多
基金the National Natural Science Foundation of China (92034301,22078063 and 22022804)Major Program of Qingyuan Innovation Laboratory (00121003)the Natural Science Foundation of Fujian Province (2020H6007)。
文摘The activation of H_(2)O is a key step of the COS hydrolysis,which may be tuned by oxygen vacancy defects in the catalysts.Herein,we have introduced Cu into Co_(3)O_(4) to regulate the oxygen vacancy defect content of the catalysts.In situ DRIFTS and XPS spectra reveal that COS and H_(2)O are adsorbed and activated by oxygen vacancy.The 10 at%Cu doped Co_(3)O_(4) sample(10Cu-Co_(3)O_(4))exhibits the optimal activity,100%of COS conversion at 70℃.The improved oxygen vacancies of CueCo_(3)O_(4) accelerate the activation of H_(2)O to form active -OH.COS binds with hydroxyl to form the intermediate HSCO^(-)_(2),and then the activated-OH on the oxygen vacancy reacts with HSCO^(-)_(2) to form HCO^(-)_(3).Meanwhile,the catalyst exhibits high catalytic stability because copper species(Cu+/Cu^(2+))redox cycle mitigate the sulfation of Co_(3)O_(4)(Co^(2+)/Co^(3+)).Our work offers a promising approach for the rational design of cobalt-related catalysts in the highly efficient hydrolysis COS process.
基金This work was supported by the National Natural Science Foundation of China(22078063,21825801).
文摘Electrochemical nitrogen reduction reaction (eNRR) is an alternative promising manner for sustainable N2 fixation with low-emission. The major challenge for developing an efficient electrocatalyst is the cleaving of the stable Ntriple bondN triple bonds. Herein, we design a new MoS_(2) with in-plane defect cluster through a bottom-up approach for the first time, where the defect cluster is composed of three adjacent S vacancies. The well-defined in-plane defect clusters could contribute to the strong chemical adsorption and activation towards inert nitrogen, achieving an excellent eNRR performance with an ammonia yield rate of 43.4 ± 3 μg h^(−1) mgcat.^(−1) and a Faradaic efficiency of 16.8 ± 2% at −0.3 V (vs. RHE). The performance is much higher than that of MoS_(2) with the edge defect. Isotopic labeling confirms that N atoms of produced NH4+ originate from N2. Furthermore, the in-plane defect clusters realized the alternate hydrogenation of nitrogen in a side-on way to synthesize ammonia. This work provides a prospecting strategy for fine-tuning in-plane defects in a catalyst, and also promotes the progress of eNRR.
基金supported by the National Natural Science Foundation of China(22022804,21978052)the Natural Science Foundation for the Distinguished Young Scholar of Fujian Province(2020J06037)the National Key Research and Development Program of China(2018YFA0209304)。
文摘Developing a suitable catalyst for the elimination of highly toxic carbonyl sulfide(COS)and hydrogen sulfide(H_(2)S) is of great significance in terms of industrial safety and environmental protection.We demonstrate here the facile synthesis of graphitized 2D micro-meso-macroporous carbons by one-step carbonization of a mixture of urea and glucose at 700–900℃.The as-synthesized graphitized catalysts,designated as 2DNHPC-x(x=urea/glucose mass ratio),are endowed with an ultra-high concentration(12.9–20.2 wt%)of stable and versatile nitrogen sites(e.g.pyrrole and pyridine)which are anchored on the surface via stable covalent bonding.As a result,the 2D-NHPC-x are active in catalytic hydrolysis of COS on pyrrolic N to H_(2)S,and the H_(2)S can be subsequently captured on pyridinic N and converted to elemental sulfur at ambient conditions over the same materials.Among the prepared catalysts,2D-NHPC-x can catalytically hydrolysize 91%of COS to H_(2)S at 30℃,whereas the conversion ratio over the common catalysts g-C_(3)N_(4)and Fe_(2)O_(3)are below 6.0%.Furthermore,these catalysts also exhibit H_(2)S conversion and sulfur selectivity of nearly 100%at 180℃with long-time durability,which is higher than those of the most reported carbonbased catalysts.In contrast,the H_(2)S capacities of activated carbon,ordered mesoporous carbons(OMC)and N-doped OMC are 3.9,1.5 and2.39 mmol g^(-1),respectively.Both the experimental and theoretical results are disclosed that 2D-NHPC-x are superior to the nitrogen-doped porous materials ever applied in simultaneous catalytic elimination of both COS and H_(2)S.
基金supported by the National Natural Science Foundation of China(Nos.22078322,21890762,22178344,and 21834006)the Youth Innovation Promotion Association CAS(No.Y2021022).
文摘Electrocatalytic depolymerization of lignin into value-added chemicals offers a promising technique to make biorefining sustainable.Herein,we report a robust trimetallic PdNiBi electrocatalyst for reductive C–O bond cleavage of different lignin model dimers and oxidized lignin under mild conditions.The reduction reaction proceeds with complete substrate conversion and excellent yields toward monomers of phenols(80%–99%)and acetophenones(75%–96%)in the presence of an ionic liquid electrolyte with operational stability.Systematic experimental investigations together with density functional theory(DFT)calculations reveal that the outstanding performance of the catalyst results from the synergistic effect of the metal elements,which facilitates the easier formation of a key Cαradical intermediate and the facile desorption of the as-formed products at the electrode.The results open up new opportunities for lignin valorization through the green electrocatalytic approach.
基金supported by the National Key R&D Program of China(2021YFB4000400),the National Natural Science Foundation of China(21825801 and 21972019),Fujian Science and Technology Major Project(2020HZ07009),and the Talent Program of Fuzhou University(XRC-22036).
文摘Fossil fuels still dominate global energy structure in our modern society,and have led to massive CO_(2) emissions.Recently,ammonia has been regarded as a clean energy carrier toward diminishing or even eliminating the CO_(2) emissions and has received significant attention.The ammonia can be synthesized from atmospheric dinitrogen and green hydrogen from water electrolysis by renewable energies,and converted back into dinitrogen and water for energy release,as shown in Figure 1.Benefited from the matured ammonia manufacture and transportation throughout the world for over one century,the already existing high-capacity infrastructure helps efficient storage and redistribution of ammonia with lowest economic cost.However,although considerable progress has been made in this artificial nitrogen cycle,there are still many challenges in developing highly-efficient routes and catalysts.Herein,we evaluate the current catalytic routes of ammonia synthesis(including thermocatalytic synthesis,electrocatalytic synthesis and photocatalytic synthesis)and ammonia utilization(involving ammonia decomposition,direct ammonia fuel cells and ammonia combustion).We also discuss the key issue in each process,and anticipate that our viewpoints and opinions could facilitate the developments of artificial nitrogen cycle and energy decarbonization.
基金supported by the National Natural Science Fund for Distinguished Young Scholars of China(No.21825801)National Natural Science Foundation of China(Nos.21677036,21878052 and 21773030)。
文摘Being abundant and active,Fe_(2)O_(3) is suitable for selective oxidation of H_(2)S.However,its practical application is limited due to the poor sulfur selectivity and rapid deactivation.Herein,we report a facile template-free hydrothermal method to fabricate porousα-Fe_(2)O_(3)/SnO_(2) composites with hierarchical nanoflower that can obviously improve the catalytic performance of Fe_(2)O_(3).It was disclosed that the synergistic effect betweenα-Fe_(2)O_(3) and SnO_(2) promotes the physico-chemical properties ofα-Fe_(2)O_(3)/SnO_(2) composites.Specifically,the electron transfer between the Fe^(2+)/Fe^(3+)and Sn^(2+)/Sn^(4+)redox couples enhances the reducibility ofα-Fe_(2)O_(3)/SnO_(2) composites.The number of oxygen vacancies is improved when the Fe cations incorporate into SnO_(2) structure,which facilitates the adsorption and activation of oxygen species.Additionally,the porous structure improves the accessibility of H_(2) S to active sites.Among the composites,Fe1 Sn1 exhibits complete H_(2) S conversion with 100%sulfur selectivity at 220℃,better than those of pureα-Fe_(2)O_(3) and SnO2.Moreover,Fe1 Sn1 catalyst shows high stability and water resistance.
基金support from the Na-tional Natural Science Foundation of China(22038002,21825801,21908028,22178058,21972019,22178061)the National Key RDProgram of China for Renewable Energy and HydrogenTechnology(2020YFB1505604)FujianScience and Technol-ogyMajor Project(202OHZO7009)。
文摘Ammonia is a key component in fertilizer and the carbon-free hydrogen carrier.Catalytic ammonia synthesis and utilization have played a central role in the development of chemical engineering.The industrial production of ammonia remains dependent on the energy-and carbon-intensive Haber-Bosch process.A major effort has been devoted to developing robust and efficient catalysts,as well as alternative benign processes.Herein,we detail our endeavors that develop the ammonia synthesis and decomposition catalysts,and utilize the ammonia energy.We firstly discuss the catalysts for ammonia synthesis via dissociative and associative process,and the regulation of catalysts'properties.Then,we review the burgeoning electrocata-lytic nitrogen reduction process,focusing on the enhanced catalytic performances by the regulation of the catalysts and the electrode.Additionally,we provide a novel high-value utilization of ammonia to achieve the"zero-carbon"circular economy.The promising catalysts,reactors,and ammonia energy systems have been discussed in detail.We end this Account that offers future research directions and prospects of ammonia.
基金The authors gratefully acknowledge the financial support from the National Natural Science Foundation of China(21905049,21902030,22108129,and 21677036)the Award Program for Minjiang Scholar Professorshipthe Natural Science Foundation of Fujian Province(2020J01201).
文摘Dye-sensitized photocatalysis has been extensively studied for photocatalytic solar energy conversion due to the advantage in capturing long-wavelength photons with a high absorption coefficient.The rational integration of photosensitizer with semiconductor and cocatalyst to collaboratively operate in one system is highly desired.Here,we fabricate a Ni(OH)_(2)-loaded titanate nanosheet(Ni(OH)_(2)/H_(2)Ti_(6)O_(13))composite for high-performance dye-sensitized photocatalytic CO_(2) reduction.The ultrathin H_(2)Ti_(6)O_(13) nanosheets with negative surface charge provide an excellent support to anchor the dye photosensitizer,while the loaded Ni(OH)2 serves as an adsorbent of CO_(2) and electron sink of photoelectrons.As such,the photoelectrons derived from the[Ru(bpy)3]Cl_(2) sensitizer can be targeted transfer to the Ni(OH)_(2) active sites via the H_(2) Ti_(6)O_(13) nanosheets linker.A high CO production rate of 1801μmol g^(-1) h^(-1) is obtained over the optimal Ni(OH)_(2)/H_(2)Ti_(6)O_(13),while the pure H_(2)Ti_(6)O_(13) shows significantly lower CO_(2) reduction performance.The work is anticipated to trigger more research attention on the rational design and synthesis of earth-abundant transition metal-based cocatalysts decorated on ultrathin 2D platforms for artificially photocatalytic CO_(2) reduction.
基金This study was supported by the National Natural Science Foundation of China(grant no.42071022)the start-up fund provided by Southern University of Science and Technology(no.29/Y01296122).
文摘Reforestation is an eco-friendly strategy for countering rising carbon dioxide concentrations in the atmosphere and the negative effects of forest loss and degradation.China,with one of the world’s most considerable afforestation rates,has increased its forest cover from 16.6%20 years ago to 23.0%by 2020.However,the maximum potential forest coverage achieved via tree planting and restoration is uncertain.To map potential tree coverage across China,we developed a random forest regression model relating environmental factors and appropriate forest types.We estimate 67.2 million hectares of land currently available for tree restoration after excluding existing forested areas,urban areas,and agriculture land covers/uses,which is 50%higher than the current understanding.Converting these lands to the forest would generate 3.99 gigatons of new above-and belowground carbon stocks,representing an important contribution to achieving carbon neutrality.This potential is spatially imbalanced,with the largest restorable carbon potential being located in the southwest(29.5%),followed by the northeast(17.2%)and northwest(16.8%).Our study highlights the need to align tree restoration areas with the uneven distribution of carbon sequestration potential.In addition to being a biological mitigation strategy to partially offset carbon dioxide emissions from fossil fuel burning,reforestation should provide other environmental services such as the restoration of degraded soils,conservation of biological diversity,revitalization of hydrological integrity,localized cooling,and improvement in air quality.Because of the collective benefits of forest restoration,we encourage that such activities be ecosystem focused as opposed to solely focusing on tree planting.
