Mandal Arnab, Gupta Shresth, Dutta Supriti, Pati Swapan K, Bhattacharyya Sayan
Department of Chemical Sciences and Centre for Advanced Functional Materials, Indian Institute of Science Education and Research (IISER) Kolkata Mohanpur - 741246 India
Theoretical Sciences Unit, School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR) Bangalore 560064 India.
Chem Sci. 2023 Aug 22;14(36):9770-9779. doi: 10.1039/d3sc01919e. eCollection 2023 Sep 20.
New perovskite phases having diverse optoelectronic properties are the need of the hour. We present five variations of RAgM(iii)X, where R = NHCHNH (4N4) or NHCHNH (6N6); M(iii) = Bi or Sb; and X = Br or I, by tuning the composition of (4N4)AgBiBr, a structurally rich hybrid layered double perovskite (HLDP). (4N4)AgBiBr, (4N4)AgSbBr, and (6N6)AgBiBr crystallize as Dion-Jacobson (DJ) HLDPs, whereas 1D (6N6)SbBr, (4N4)-BiI and (4N4)-SbI have -connected chains by corner-shared octahedra. Ag stays out of the 1D lattice either when SbBr distortion is high or if Ag needs to octahedrally coordinate with I. Band structure calculations show a direct bandgap for all the bromide phases except (6N6)AgBiBr. (4N4)AgBiBr with lower octahedral tilt shows a maximum UV responsivity of 18.8 ± 0.2 A W and external quantum efficiency (EQE) of 6360 ± 58%, at 2.5 V. When self-powered (0 V), (4N4)-SbI has the best responsivity of 11.7 ± 0.2 mA W under 485 nm visible light, with fast photoresponse ≤100 ms.
当下急需具有多样光电特性的新型钙钛矿相。我们通过调整结构丰富的混合层状双钙钛矿（HLDP）(4N4)AgBiBr的组成，展示了RAgM(iii)X的五种变体，其中R = NHCHNH (4N4) 或NHCHNH (6N6)；M(iii) = Bi或Sb；X = Br或I。(4N4)AgBiBr、(4N4)AgSbBr和(6N6)AgBiBr结晶为迪翁 - 雅各布森（DJ）HLDPs，而一维的(6N6)SbBr、(4N4)-BiI和(4N4)-SbI通过角共享八面体形成相连的链。当SbBr畸变较高或Ag需要与I进行八面体配位时，Ag不在一维晶格中。能带结构计算表明，除(6N6)AgBiBr外，所有溴化物相均具有直接带隙。八面体倾斜度较低的(4N4)AgBiBr在2.5 V时显示出最大紫外响应度为18.8 ± 0.2 A W，外部量子效率（EQE）为6360 ± 58%。当自供电（0 V）时，(4N4)-SbI在485 nm可见光下具有最佳响应度11.7 ± 0.2 mA W，光响应速度快，≤100 ms。
