The efficiency of perovskite solar cells(PSCs) has increased from around 4% to over 22% following a few years of intensive investigation. For most PSCs, organic materials such as 2,2',7,7'-tetrakis(N,Npdimethoxyp...The efficiency of perovskite solar cells(PSCs) has increased from around 4% to over 22% following a few years of intensive investigation. For most PSCs, organic materials such as 2,2',7,7'-tetrakis(N,Npdimethoxyphenylamino)-9,9'-spirobifluorene(spiro-OMeTAD) are used as the hole transporting materials(HTMs), which are thermally and chemically unstable and also expensive. Here, we explored nickel phthalocyanine(NiPc) as a stable and cost-effective HTM to replace the conventionally used spiroOMeTAD. Because of its high carrier mobility and proper band alignments, we achieved a PCE of 12.1% on NiPc based planar device with short-circuit current density(Jsc) of 17.64 mAcm(-2), open circuit voltage(Voc) of 0.94 V, and fill factor(FF) of 73%, outperforming the planar device based on copper phthalocyanine(CuPc) that is an outstanding representative of metal phthalocyanines(MPcs) reported. Moreover,the device with NiPc shows much improved stability compared to that based on the conventional spiroOMeTAD as a result of NiPc's high stability. Photoluminescence(PL) and Impedance spectroscopy analysis results show that thermally deposited NiPc has good hole-extraction ability. Our results suggest that NiPc is a promising HTM for the large area, low cost and stable PSCs.展开更多
In the past several years, perovskite solar cells (PSCs)exhibited unexpected breakthrough and rapid evolution,and the power conversion efficiency (PCE) of singlejunction PSCs has been increased significantly from 3.81...In the past several years, perovskite solar cells (PSCs)exhibited unexpected breakthrough and rapid evolution,and the power conversion efficiency (PCE) of singlejunction PSCs has been increased significantly from 3.81 to25.2%[1, 2], resulting from materials engineering, interface engineering, crystallization engineering, fabrication engineering, etc.[3-5]. In the case of silicon solar cells.展开更多
Metal phthalocyanine is considered one of the most promising candidates for the design and fabrication of flexible resistive random access memory(RRAM)devices due to its intrinsic flexibility and excellent functionali...Metal phthalocyanine is considered one of the most promising candidates for the design and fabrication of flexible resistive random access memory(RRAM)devices due to its intrinsic flexibility and excellent functionality.However,performance degradation and the lack of multi-level capability,which can directly expand the storage capacity in one memory cell without sacrificing additional layout area,are the primary obstacles to the use of metal phthalocyanine RRAMs in information storage.Here,a flexible RRAM with pristine nickel phthalocyanine(Ni Pc)as the resistive layer is reported for multi-level data storage.Due to its high trap-concentration,the charge transport behavior of the device agrees well with classical space charge limited conduction controlled by traps,leading to an excellent performance,including a high on-off current ratio of 10^(7),a long-term retention of 10^(6)s,a reproducible endurance over6000 cycles,long-term flexibility at a bending strain of 0.6%,a write speed of 50 ns under sequential bias pulses and the capability of multi-level data storage with reliable retention and uniformity.展开更多
SnO_2 quantum dots(QDs) ended with chlorine ions are introduced at the interface of spin-coated TiO_2 electron selective layer(ESL)/perovskite to fill the pinholes in the layer and passivate the trapping defects. As a...SnO_2 quantum dots(QDs) ended with chlorine ions are introduced at the interface of spin-coated TiO_2 electron selective layer(ESL)/perovskite to fill the pinholes in the layer and passivate the trapping defects. As a result of the increased interface electron collection and reduced bulk recombination, the planar perovskite solar cell with the QDs modified ESL gives the large power conversion efficiency enhancement from 14.9% to 17.3% and greatly improved stability under the continuous light irradiation.展开更多
基金the Major Basic Research Program, Ministry of Science and Technology of China (2014CB239401)the National Natural Science Foundation of China (Nos. 51402306, 51422210, 51629201, 51521091)the Key Research Program of Frontier Sciences CAS (QYZDB-SSW-JSC039) for the financial support
文摘The efficiency of perovskite solar cells(PSCs) has increased from around 4% to over 22% following a few years of intensive investigation. For most PSCs, organic materials such as 2,2',7,7'-tetrakis(N,Npdimethoxyphenylamino)-9,9'-spirobifluorene(spiro-OMeTAD) are used as the hole transporting materials(HTMs), which are thermally and chemically unstable and also expensive. Here, we explored nickel phthalocyanine(NiPc) as a stable and cost-effective HTM to replace the conventionally used spiroOMeTAD. Because of its high carrier mobility and proper band alignments, we achieved a PCE of 12.1% on NiPc based planar device with short-circuit current density(Jsc) of 17.64 mAcm(-2), open circuit voltage(Voc) of 0.94 V, and fill factor(FF) of 73%, outperforming the planar device based on copper phthalocyanine(CuPc) that is an outstanding representative of metal phthalocyanines(MPcs) reported. Moreover,the device with NiPc shows much improved stability compared to that based on the conventional spiroOMeTAD as a result of NiPc's high stability. Photoluminescence(PL) and Impedance spectroscopy analysis results show that thermally deposited NiPc has good hole-extraction ability. Our results suggest that NiPc is a promising HTM for the large area, low cost and stable PSCs.
文摘In the past several years, perovskite solar cells (PSCs)exhibited unexpected breakthrough and rapid evolution,and the power conversion efficiency (PCE) of singlejunction PSCs has been increased significantly from 3.81 to25.2%[1, 2], resulting from materials engineering, interface engineering, crystallization engineering, fabrication engineering, etc.[3-5]. In the case of silicon solar cells.
基金supported by National Natural Science Foundation of China(Nos.61574143,61704175,51502304)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB30000000)+2 种基金the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(No.ZDBS-LY-JSC027)Liaoning Revitalization Talents Program(No.XLYC1807109)the National Key Research and Development Program of China(2016YFB0401104)。
文摘Metal phthalocyanine is considered one of the most promising candidates for the design and fabrication of flexible resistive random access memory(RRAM)devices due to its intrinsic flexibility and excellent functionality.However,performance degradation and the lack of multi-level capability,which can directly expand the storage capacity in one memory cell without sacrificing additional layout area,are the primary obstacles to the use of metal phthalocyanine RRAMs in information storage.Here,a flexible RRAM with pristine nickel phthalocyanine(Ni Pc)as the resistive layer is reported for multi-level data storage.Due to its high trap-concentration,the charge transport behavior of the device agrees well with classical space charge limited conduction controlled by traps,leading to an excellent performance,including a high on-off current ratio of 10^(7),a long-term retention of 10^(6)s,a reproducible endurance over6000 cycles,long-term flexibility at a bending strain of 0.6%,a write speed of 50 ns under sequential bias pulses and the capability of multi-level data storage with reliable retention and uniformity.
基金financially supported by the National Natural Science Foundation of China (51825204)the Key Research Program of Frontier Sciences CAS (QYZDB-SSW-JSC039)
文摘SnO_2 quantum dots(QDs) ended with chlorine ions are introduced at the interface of spin-coated TiO_2 electron selective layer(ESL)/perovskite to fill the pinholes in the layer and passivate the trapping defects. As a result of the increased interface electron collection and reduced bulk recombination, the planar perovskite solar cell with the QDs modified ESL gives the large power conversion efficiency enhancement from 14.9% to 17.3% and greatly improved stability under the continuous light irradiation.