Spicy crayfish has many diehard fans In Beijing.People wait in line for more than two hours or more at Huda Restaurant,renowned for its spicy crayfish.But do you know where all those crayfish come from?Huang Jianxiong...Spicy crayfish has many diehard fans In Beijing.People wait in line for more than two hours or more at Huda Restaurant,renowned for its spicy crayfish.But do you know where all those crayfish come from?Huang Jianxiong,Secretary of the Communist Party of China(CPC)Qianjiang City Committee,told Beijing Review at a recent seminar in展开更多
Introduction In English teaching, the first task for teachers should be teaching students with clear information about the language they are learning. The presentation stage is the best way to reach this goal. In this...Introduction In English teaching, the first task for teachers should be teaching students with clear information about the language they are learning. The presentation stage is the best way to reach this goal. In this essay, we analyze the importance of this stage. How it is different from the traditional methods -grammatical explanation and translations methods- and its advantages.展开更多
The valence band offset between Cs_(2)AgBiBr_(6)and hole transport layer(HTL)is approximately 1.00 e V,which results in high energy loss and is identified as one of the bottle necks of Cs_(2)Ag BiBr_(6)perovskite sola...The valence band offset between Cs_(2)AgBiBr_(6)and hole transport layer(HTL)is approximately 1.00 e V,which results in high energy loss and is identified as one of the bottle necks of Cs_(2)Ag BiBr_(6)perovskite solar cell(PSC)for achieving high power conversion efficiency(PCE).To tackle this problem,we propose the optimization of the energy level alignment by designing and synthesizing novel deep-level hole transport materials(HTMs).The sole introduction of deep-level HTMs successfully reduces the valence band offset between Cs_(2)Ag Bi Br_(6)and HTL,but induces the increased valence band offset at HTL/Au interface,limiting the PCE improvement.To further solve the problem and improve the PCE,the gradient energy level arrangement is constructed by combining the newly developed deep-level HTM 6,6’-(3-((9,9-dimethyl-9H-fluoren-3-yl)(4-methoxyphenyl)amino)thiophene-2,5-diyl)bis(N-(9,9-dimethyl-9H-fluoren-2-yl)-N,9-bis(4-methoxyphenyl)-9H-carbazol-3-amine)(TF)with 2,2’,7,7’-tetrakis(N,N’-dipmethoxyphenylamine)-9,9-spirobifluorene(Spiro-OMeTAD).Through optimization,an impressive PCE of 3.50%with remarkably high open-circuit voltage(V_(oc))and fill factor(FF)is achieved,qualifying it among the best pristine Cs_(2)AgBiBr_(6)PSCs.展开更多
文摘Spicy crayfish has many diehard fans In Beijing.People wait in line for more than two hours or more at Huda Restaurant,renowned for its spicy crayfish.But do you know where all those crayfish come from?Huang Jianxiong,Secretary of the Communist Party of China(CPC)Qianjiang City Committee,told Beijing Review at a recent seminar in
文摘Introduction In English teaching, the first task for teachers should be teaching students with clear information about the language they are learning. The presentation stage is the best way to reach this goal. In this essay, we analyze the importance of this stage. How it is different from the traditional methods -grammatical explanation and translations methods- and its advantages.
基金financially supported by the National Natural Science Foundation of China(Nos.22179053,22279046 and 21905119)the Natural Science Excellent Youth Foundation of Jiangsu Provincial(No.BK20220112)+1 种基金the Open Competition Mechanism Project of Carbon Neutrality of Jiangsu Province(No.BE2022026)Zhejiang Province Selected Funding for Postdoctoral Research Projects(No.ZJ2021001)for financial support。
文摘The valence band offset between Cs_(2)AgBiBr_(6)and hole transport layer(HTL)is approximately 1.00 e V,which results in high energy loss and is identified as one of the bottle necks of Cs_(2)Ag BiBr_(6)perovskite solar cell(PSC)for achieving high power conversion efficiency(PCE).To tackle this problem,we propose the optimization of the energy level alignment by designing and synthesizing novel deep-level hole transport materials(HTMs).The sole introduction of deep-level HTMs successfully reduces the valence band offset between Cs_(2)Ag Bi Br_(6)and HTL,but induces the increased valence band offset at HTL/Au interface,limiting the PCE improvement.To further solve the problem and improve the PCE,the gradient energy level arrangement is constructed by combining the newly developed deep-level HTM 6,6’-(3-((9,9-dimethyl-9H-fluoren-3-yl)(4-methoxyphenyl)amino)thiophene-2,5-diyl)bis(N-(9,9-dimethyl-9H-fluoren-2-yl)-N,9-bis(4-methoxyphenyl)-9H-carbazol-3-amine)(TF)with 2,2’,7,7’-tetrakis(N,N’-dipmethoxyphenylamine)-9,9-spirobifluorene(Spiro-OMeTAD).Through optimization,an impressive PCE of 3.50%with remarkably high open-circuit voltage(V_(oc))and fill factor(FF)is achieved,qualifying it among the best pristine Cs_(2)AgBiBr_(6)PSCs.