Two-step-processed(TSP)inverted p-i-n perovskite solar cells(PSCs)have demonstrated significant promise in tandem applications.However,the power conversion efficiency(PCE)of TSP p-i-n PSCs rarely exceeds 24%.Here,we d...Two-step-processed(TSP)inverted p-i-n perovskite solar cells(PSCs)have demonstrated significant promise in tandem applications.However,the power conversion efficiency(PCE)of TSP p-i-n PSCs rarely exceeds 24%.Here,we demonstrate that TSP perovskite films exhibit a vertically gradient distribution of residual PbI_(2)clusters,which form Schottky heterojunctions with the perovskite,leading to substantial interfacial energy-level mismatches within NiO_(x)-based TSP p-i-n PSCs.These limitations were effectively addressed via a vertical interfacial engineering enabled by dual-interface modification incorporating tin trifluoromethanesulfonate(Sn(OTF)_(2))and 4-Fluorophenylethylamine chloride(F-PEA)at the NiO_(x)/perovskite and perovskite/C60 interfaces,respectively.The functional Sn(OTF)_(2)not only enhances the conductivity of NiO_(x)films but also suppresses ion migration,while inducing the formation of a Pb-Sn mixed perovskite interlayer that precisely regulates the energy level at the NiO_(x)/perovskite interface.Complementally,F-PEA post-treatment effectively converts surface residual PbI_(2)clusters into a 2D perovskite capping layer,which simultaneously passivates surface defects and enhances energy-level alignment at the perovskite/C60 interface.Consequently,the optimized NiO_(x)-based TSP p-i-n PSCs achieve a notable PCE of 25.6%with superior operational stability.This study elucidates the underlying mechanisms limiting the efficiency of TSP p-i-n PSCs,while establishing design principles for these devices targeting 26%efficiency.展开更多
The rapid development of communication technology and high-frequency electronic devices has created a need for more advanced electromagnetic interference(EMI)shielding materials.In response to this demand,a study has ...The rapid development of communication technology and high-frequency electronic devices has created a need for more advanced electromagnetic interference(EMI)shielding materials.In response to this demand,a study has been conducted to develop multifunctional carbon nanofibers(CNFs)/polyaniline(PANI)aerogels with excellent electromagnetic interference shielding,flame retardancy,and thermal insulation performance.The process involved freeze-drying of electrospun CNFs and PANI nanoparticles followed by in situ growth PANI to coat the CNFs,creating the core-shell structured CNFs/PANI composite fiber and its hybrid aerogels(CP-3@PANI).The interaction between PANI and aniline(ANI)provides attachment sites,allowing additional ANI adsorption into the aerogel for in situ polymerization.This results in PANI uniformly covering the surface of the CNFs,creating a core-shell composite fiber with a flexible CNF core and PANI shell.This process enhances the utilization rate of the ANI monomer and increases the PANI content loaded onto the aerogel.Additionally,effective connections are established between the CNFs,forming a stable,conductive three-dimensional network structure.The prepared CP-3@PANI aerogels exhibit excellent EMI shielding efficiency(SE)of 85.4 dB and specific EMI SE(SE d^(-1))of 791.2 dB cm^(3)g^(-1)in the X-band.Due to the synergistic flame-retardant effect of CNFs,PANI,and the dopant(phytic acid),the CP-3@PANI aerogels demonstrate outstanding flame-retardant and thermal insulation properties,with a peak heat release rate(PHRR)as low as 7.8 W g^(-1)and a total heat release of only 0.58 kJ g^(-1).This study provides an effective strategy for preparing multifunctional integrated EMI shielding materials.展开更多
Gut microbes exhibit complex interactions with their hosts and shape an organism's immune system throughout its lifespan.As the largest secondary lymphoid organ,the spleen has a wide range of immunological functio...Gut microbes exhibit complex interactions with their hosts and shape an organism's immune system throughout its lifespan.As the largest secondary lymphoid organ,the spleen has a wide range of immunological functions.To explore the role of microbiota in regulating and shaping the spleen,we employ scRNA-seq and Stereo-seq technologies based on germ-free(GF)mice to detect differences in tissue size,anatomical structure,cell types,functions,and spatial molecular characteristics.We identify 18 cell types,9 subtypes of T cells,and 7 subtypes of B cells.Gene differential expression analysis reveals that the absence of microorganisms results in alterations in erythropoiesis within the red pulp region and congenital immune deficiency in the white pulp region.Stereo-seq results demonstrate a clear hierarchy of immune cells in the spleen,including marginal zone(MZ)macrophages,MZ B cells,follicular B cells and T cells,distributed in a well-defined pattern from outside to inside.However,this hierarchical structure is disturbed in GF mice.Ccr7 and Cxcl13 chemokines are specifically expressed in the spatial locations of T cells and B cells,respectively.We speculate that the microbiota may mediate the structural composition or partitioning of spleen immune cells by modulating the expression levels of chemokines.展开更多
Myeloid cells are pivotal in the inflammatory and remodeling phases of fracture repair.Here,we investigate the effect of periostin expressed by myeloid cells on bone regeneration in a monocortical tibial defect(MTD)mo...Myeloid cells are pivotal in the inflammatory and remodeling phases of fracture repair.Here,we investigate the effect of periostin expressed by myeloid cells on bone regeneration in a monocortical tibial defect(MTD)model.In this study,we show that periostin is expressed by periosteal myeloid cells,primarily the M2 macrophages during bone regeneration.Knockout of periostin in myeloid cells reduces cortical bone thickness,disrupts trabecular bone connectivity,impairs repair impairment,and hinders M2 macrophage polarization.Mechanical stimulation is a regulator of periostin in macrophages.By activating transforming growth factor-β(TGF-β),it increases periostin expression in macrophages and induces M2 polarization.This mechanosensitive effect also reverses the delayed bone repair induced by periostin deficiency in myeloid cells by strengthening the angiogenesis-osteogenesis coupling.In addition,transplantation of mechanically conditioned macrophages into the periosteum over a bone defect results in substantially enhanced repair,confirming the critical role of macrophage-secreted periostin in bone repair.In summary,our findings suggest that mechanical stimulation regulates periostin expression and promotes M2 macrophage polarization,highlighting the potential of mechanically conditioned macrophages as a therapeutic strategy for enhancing bone repair.展开更多
Radioactive iodine element mainly in CH3I is a key fission product of concern in the nuclear fuel cycle,which directly threat-ens human health if released into the environment.Effective capture of the I element is ess...Radioactive iodine element mainly in CH3I is a key fission product of concern in the nuclear fuel cycle,which directly threat-ens human health if released into the environment.Effective capture of the I element is essential for human health protection.The iodine filter,consisting of an activated carbon inner core and cotton filter,is the most common radioactive iodine pro-tection product.Currently,the activated carbon inside the iodine filter suffers from the weak adsorption efficiency and high cost.Herein,a process based on a strong alkali activation method was developed to significantly improve iodine absorption and reduce the cost.A series of flexible porous carbon fibers with a high specific surface area(up to about 1,500~2,200 m^(2)/g)were prepared by carbonation of the phenolic resin fibers(PF,prepared through melt spinning and crosslink)followed by activation via KOH treatment.Meanwhile,the nitrogen-doped sp^(2)-heterogeneous carbon atoms were prepared by add-ing nitrogen sources such as urea which led to a high surface area nano-porous fibers with an average pore size of~2.4 nm.The nitrogen-doped porous carbon fibers exhibit very high adsorption for liquid iodine and iodine vapor.The liquid iodine adsorption capacity of nitrogen-doped porous carbon NDAC-4 prepared under 800°C reaches 2,120 mg/g,which is 2.1 times higher than that of the commercial iodine filter,and for iodine vapor the capacity can reach 5,330 mg/g.Meanwhile,the CH_(3)I adsorption capacity is 510 mg/g,which is 3.4 times higher than that of commercial unmodified viscose fibers and has greater stability and circularity.Importantly,the research has met the requirements of industrial production,and the fabrication of phenolic-fibers-based protection equipment can be widely used in the nuclear radiation industry.展开更多
基金financially supported by the National Nature Science Foundation of China (62504130)National Key Research and Development Program of China (2018YFB0704100)+3 种基金the Key university laboratory of highly efficient utilization of solar energy and sustainable development of Guangdong (Y01256331)the Technology Development Project of Henan Province (252102240047)the Pico Center at SUSTech CRF which receives support from the Presidential FundDevelopment and Reform Commission of Shenzhen Municipality
文摘Two-step-processed(TSP)inverted p-i-n perovskite solar cells(PSCs)have demonstrated significant promise in tandem applications.However,the power conversion efficiency(PCE)of TSP p-i-n PSCs rarely exceeds 24%.Here,we demonstrate that TSP perovskite films exhibit a vertically gradient distribution of residual PbI_(2)clusters,which form Schottky heterojunctions with the perovskite,leading to substantial interfacial energy-level mismatches within NiO_(x)-based TSP p-i-n PSCs.These limitations were effectively addressed via a vertical interfacial engineering enabled by dual-interface modification incorporating tin trifluoromethanesulfonate(Sn(OTF)_(2))and 4-Fluorophenylethylamine chloride(F-PEA)at the NiO_(x)/perovskite and perovskite/C60 interfaces,respectively.The functional Sn(OTF)_(2)not only enhances the conductivity of NiO_(x)films but also suppresses ion migration,while inducing the formation of a Pb-Sn mixed perovskite interlayer that precisely regulates the energy level at the NiO_(x)/perovskite interface.Complementally,F-PEA post-treatment effectively converts surface residual PbI_(2)clusters into a 2D perovskite capping layer,which simultaneously passivates surface defects and enhances energy-level alignment at the perovskite/C60 interface.Consequently,the optimized NiO_(x)-based TSP p-i-n PSCs achieve a notable PCE of 25.6%with superior operational stability.This study elucidates the underlying mechanisms limiting the efficiency of TSP p-i-n PSCs,while establishing design principles for these devices targeting 26%efficiency.
基金the financial support from the Shenzhen Biodegradable Polymer Materials and Materials Genetic Evaluation Research Project Team (JCYJ20220818100217037)Science and Technology Program of Shenzhen (JSGG20200924171000001)+4 种基金the Key-Area Research and Development Program of Guangdong Province (2019B010941001)the Guangdong Provincial Key Laboratory of Energy Materials for Electric Power(2018B030322001)the National Key Research and Development Program of China (2018YFB0704100)Joint Laboratory of Radiation Protection and Material Genetic Engineering Applications in Nuclear Facilitiessupported by the Pico Center at SUSTech CRF which receives support from the Presidential Fund and Development and Reform Commission of Shenzhen Municipality。
文摘The rapid development of communication technology and high-frequency electronic devices has created a need for more advanced electromagnetic interference(EMI)shielding materials.In response to this demand,a study has been conducted to develop multifunctional carbon nanofibers(CNFs)/polyaniline(PANI)aerogels with excellent electromagnetic interference shielding,flame retardancy,and thermal insulation performance.The process involved freeze-drying of electrospun CNFs and PANI nanoparticles followed by in situ growth PANI to coat the CNFs,creating the core-shell structured CNFs/PANI composite fiber and its hybrid aerogels(CP-3@PANI).The interaction between PANI and aniline(ANI)provides attachment sites,allowing additional ANI adsorption into the aerogel for in situ polymerization.This results in PANI uniformly covering the surface of the CNFs,creating a core-shell composite fiber with a flexible CNF core and PANI shell.This process enhances the utilization rate of the ANI monomer and increases the PANI content loaded onto the aerogel.Additionally,effective connections are established between the CNFs,forming a stable,conductive three-dimensional network structure.The prepared CP-3@PANI aerogels exhibit excellent EMI shielding efficiency(SE)of 85.4 dB and specific EMI SE(SE d^(-1))of 791.2 dB cm^(3)g^(-1)in the X-band.Due to the synergistic flame-retardant effect of CNFs,PANI,and the dopant(phytic acid),the CP-3@PANI aerogels demonstrate outstanding flame-retardant and thermal insulation properties,with a peak heat release rate(PHRR)as low as 7.8 W g^(-1)and a total heat release of only 0.58 kJ g^(-1).This study provides an effective strategy for preparing multifunctional integrated EMI shielding materials.
基金funded by the National Natural Science Foundation of China(81700436)the Science Technology and Innovation Committee of Shenzhen Municipality,China(SGDX20190919142801722)。
文摘Gut microbes exhibit complex interactions with their hosts and shape an organism's immune system throughout its lifespan.As the largest secondary lymphoid organ,the spleen has a wide range of immunological functions.To explore the role of microbiota in regulating and shaping the spleen,we employ scRNA-seq and Stereo-seq technologies based on germ-free(GF)mice to detect differences in tissue size,anatomical structure,cell types,functions,and spatial molecular characteristics.We identify 18 cell types,9 subtypes of T cells,and 7 subtypes of B cells.Gene differential expression analysis reveals that the absence of microorganisms results in alterations in erythropoiesis within the red pulp region and congenital immune deficiency in the white pulp region.Stereo-seq results demonstrate a clear hierarchy of immune cells in the spleen,including marginal zone(MZ)macrophages,MZ B cells,follicular B cells and T cells,distributed in a well-defined pattern from outside to inside.However,this hierarchical structure is disturbed in GF mice.Ccr7 and Cxcl13 chemokines are specifically expressed in the spatial locations of T cells and B cells,respectively.We speculate that the microbiota may mediate the structural composition or partitioning of spleen immune cells by modulating the expression levels of chemokines.
基金supported by grants from Shenzhen Science and Technology Innovation Commission (KQTD20200820113012029,JCYJ20190809114209434)。
文摘Myeloid cells are pivotal in the inflammatory and remodeling phases of fracture repair.Here,we investigate the effect of periostin expressed by myeloid cells on bone regeneration in a monocortical tibial defect(MTD)model.In this study,we show that periostin is expressed by periosteal myeloid cells,primarily the M2 macrophages during bone regeneration.Knockout of periostin in myeloid cells reduces cortical bone thickness,disrupts trabecular bone connectivity,impairs repair impairment,and hinders M2 macrophage polarization.Mechanical stimulation is a regulator of periostin in macrophages.By activating transforming growth factor-β(TGF-β),it increases periostin expression in macrophages and induces M2 polarization.This mechanosensitive effect also reverses the delayed bone repair induced by periostin deficiency in myeloid cells by strengthening the angiogenesis-osteogenesis coupling.In addition,transplantation of mechanically conditioned macrophages into the periosteum over a bone defect results in substantially enhanced repair,confirming the critical role of macrophage-secreted periostin in bone repair.In summary,our findings suggest that mechanical stimulation regulates periostin expression and promotes M2 macrophage polarization,highlighting the potential of mechanically conditioned macrophages as a therapeutic strategy for enhancing bone repair.
基金The authors acknowledge the financial support from Key-Area Research and Development Program of Guangdong Province(2019B010941001)Science and Technology Program of Shenzhen(JSGG20200924171000001)+3 种基金Shenzhen Science and Technology Innovation Committee(no.JCYJ20200109140812302)2019 Dong guan Postgraduate Joint Training(Practice)Workstation Project(Grant No.2019707126017)Department of Science and Technology of Guangdong Province(2017ZT07Z479)Atomic-resolution high-angle annular darkfield(HAADF)-scanning TEM(STEM)was carried out on microscope Titan Themis G260-300 maintained by Southern University of Science and Technology Core Research facilities.
文摘Radioactive iodine element mainly in CH3I is a key fission product of concern in the nuclear fuel cycle,which directly threat-ens human health if released into the environment.Effective capture of the I element is essential for human health protection.The iodine filter,consisting of an activated carbon inner core and cotton filter,is the most common radioactive iodine pro-tection product.Currently,the activated carbon inside the iodine filter suffers from the weak adsorption efficiency and high cost.Herein,a process based on a strong alkali activation method was developed to significantly improve iodine absorption and reduce the cost.A series of flexible porous carbon fibers with a high specific surface area(up to about 1,500~2,200 m^(2)/g)were prepared by carbonation of the phenolic resin fibers(PF,prepared through melt spinning and crosslink)followed by activation via KOH treatment.Meanwhile,the nitrogen-doped sp^(2)-heterogeneous carbon atoms were prepared by add-ing nitrogen sources such as urea which led to a high surface area nano-porous fibers with an average pore size of~2.4 nm.The nitrogen-doped porous carbon fibers exhibit very high adsorption for liquid iodine and iodine vapor.The liquid iodine adsorption capacity of nitrogen-doped porous carbon NDAC-4 prepared under 800°C reaches 2,120 mg/g,which is 2.1 times higher than that of the commercial iodine filter,and for iodine vapor the capacity can reach 5,330 mg/g.Meanwhile,the CH_(3)I adsorption capacity is 510 mg/g,which is 3.4 times higher than that of commercial unmodified viscose fibers and has greater stability and circularity.Importantly,the research has met the requirements of industrial production,and the fabrication of phenolic-fibers-based protection equipment can be widely used in the nuclear radiation industry.
