Mechanically robust stretchable organic optoelectronic devices built using a simple and universal stencil-pattern transferring technology

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1 Yin et l. Light: Science & Applictions (218) 7:35 Officil journl of the CIOMP DOI 1.138/s x ARTICLE Mechniclly roust stretchle orgnic optoelectronic devices uilt using simple nd universl stencil-pttern trnsferring technology D Yin 1, Ni-Rong Jing 1,Yue-FengLiu 1, Xu-Lin Zhng 1,Ai-WuLi 1,JingFeng 1 nd Hong-Bo Sun 1,2 Open Access ():,; ():,; ():,; ():,; Astrct Stretchle electronic nd optoelectronic devices sed on controllle ordered uckling structures exhiit superior mechnicl stility y retining their uckling profile without distortion in repeted stretch-relese cycles. However, simple nd universl technology to introduce ordered uckling structures into stretchle devices remins rel chllenge. Here, simple nd generl stencil-pttern trnsferring technology ws pplied to stretchle orgnic lightemitting devices (SOLEDs) nd polymer solr cells (SPSCs) to relize n ordered uckling profile. To the est of our knowledge, oth the SOLEDs nd SPSCs with periodic uckles exhiited the highest mechnicl roustness y operting with smll performnce vritions fter 2, nd 12, stretch-relese cycles etween % nd 2% tensile strin, respectively. Notly, in this work, periodic-uckled structures were introduced into SPSCs for the first time, with the numer of stretch-relese cycles for the SPSCs improved y two orders of mgnitude compred to tht for previously reported rndom-uckled stretchle orgnic solr cells. The simple method used in this work provides universl solution for low-cost nd high-performnce stretchle electronic nd optoelectronic devices nd promotes the commercil development of stretchle devices in werle electronics. Introduction Stretchle electronic nd optoelectronic devices such s stretchle light-emitting devices 1 7, solr cells 8 11, supercpcitors 12 15, tteries 16 18, conductors 19 23, nd sensors show gret potentil for next-genertion werle electronics pplictions. Among vrious strtegies to relize stretchle devices 28 33, the cretion of uckling profile in ultrthin devices hs ttrcted much ttention ecuse of its independence from mterils nd the structures of these devices, enling flexiility for Correspondence: Jing Feng (jingfeng@jlu.edu.cn) or Hong-Bo Sun (hsun@tsinghu.edu.cn) 1 Stte Key Lortory of Integrted Optoelectronics, College of Electronic Science nd Engineering, Jilin University, 2699 Qinjin Street, 1312 Chngchun, Chin 2 Stte Key Lortory of Precision Mesurement Technology nd Instruments, Deprtment of Precision Instrument, Tsinghu University, Hidin, 184 Beijing, Chin device friction Different types of uckled ultrthin film-sed stretchle electronic nd optoelectronic devices hve een reported. The process for forming the uckles determines the morphology for ultrthin films nd is importnt for the performnce of stretchle devices. Rndom uckles cn e formed y ttching n ultrthin film onto pre-strined dhesive nd elstomeric sustrte, followed y the relese of the sustrte without ny control 34,36,39,4,42. Smll-ending rdii in shrp corners nd extreme-ending regions result in lrge-ending strin, which cn dmge devices. Additionlly, the profile of rndom uckles might chnge fter cyclic stretching due to the chnging rndom onding regions etween ultrthin devices nd the elstomeric sustrte. Poor mechnicl stility is ftl disdvntge for rndom uckling stretchle devices due to the ove fctors. In contrst, devices sed on controllle ordered The Author(s) 218 Open Access Thisrticleislicensedunder CretiveCommons Attriution 4. InterntionlLicense, which permitsuse, shring, dpttion, distriution nd reproduction in ny medium or formt, s long s you give pproprite credit to the originl uthor(s) nd the source, provide linktothecretivecommons license, nd indicte if chnges were mde. The imges or other third prty mteril in this rticle re included in the rticle s Cretive Commons license, unless indicted otherwise in credit line to the mteril. If mteril is not included in the rticle s Cretive Commons license nd your intended use is not permitted y sttutory regultion or exceeds the permitted use, you will need to otin permission directly from the copyright holder. To view copy of this license, visit

2 Yin et l. Light: Science & Applictions (218) 7:35 Pge 2 of 8 uckles prepred vi sophisticted configurtion design nd processing cn void the formtion of shrp corners nd extreme ending nd mintin the ordered uckling profile without distortion, which cn much improve their mechnicl stility. Introducing well-designed ordered structures on the surfce of n dhesive nd elstomeric sustrte vi the use of progrmmle lser ltion process hs een demonstrted s fesile strtegy to fricte periodic uckles for stretchle orgnic lightemitting devices (SOLEDs) with high mechnicl stility 41. However, considering tht the lser ltion system nd process is oth expensive nd complicted, simple nd low-cost technology for relizing stretchle devices with ordered uckles remins rel chllenge, which is mjor ostcle for the prcticl pplictions of stretchle devices. The stencil-pttern trnsferring technique is commonly used for copying nd trnsferring ptterns to trget sustrtes The dimension nd size of the fricted microstructures re the sme s the ptterns on the stencil. Deposited films with defined ptterns cn e directly utilized s functionl lyers, such s ptterned metl electrodes in orgnic optoelectronic devices Here, we developed simple nd generl stencil-pttern trnsferring technique for fricting ordered uckles in stretchle orgnic optoelectronic devices. A periodic metl film ws deposited onto the surfce of n dhesive nd elstomeric sustrte vi stencil nd used s rrier lyer to modify the surfce viscidity distriution of the sustrte without ffecting its elsticity. When n ultrthin optoelectronic device ws ttched onto the prestretched sustrte, onding nd nononding regions etween the device nd sustrte were defined y the periodic rrier lyer. Controllle nd ordered uckles hve een chieved fter relesing the pre-strined sustrte. SOLEDs nd polymer solr cells (SPSCs) were fricted y simple process. Notly, the SPSCs in this work re the first reported SPSCs with periodic-uckled structures. The SOLEDs nd SPSCs exhiited outstnding mechnicl stility with smll performnce vritions fter 2, nd 12, stretch-relese cycles etween % nd 2% tensile strin, respectively. The periodic-uckled SPSCs exhiited enhncements of two orders of mgnitude in the numer of stretch-relese cycles compred to tht for previously reported rndom-uckled SPSCs 11,34,43. The simple nd low-cost stencil-pttern trnsferring technique employed in this work exhiits gret potentil s universl solution for vrious stretchle electronic nd optoelectronic devices ecuse of its comptiility with vrious mterils, structures, nd friction processes for device friction; this comptiility is importnt for promoting the commercil development of stretchle electronic nd optoelectronic devices in werle electronics. Mterils nd methods Mterils Polymer sustrtes for ultrthin OLEDs nd PSCs were fricted y NOA 63 photoresist, which ws purchsed from Norlnd Products Inc. (USA). Adhesive nd elstomeric sustrtes (3 M VHB 495 tpe) nd plstic tpes (Scotch Mgic Tpe) were purchsed from the 3 M Compny (USA). Metl stencils were custom-mde y ZLDSK Corportion (Chin). MoO 3, NPB (N,N diphenyl- N,N -is(1,1 -iphenyl)-4,4 -dimine), CBP (4,4 -is (N-crzolyl)-1, 1 -iphenyl), Ir(BT) 2 (cc) (2,3,5,6-tetrkis(3,6-diphenylcrzol-9-yl)-1,4-dicynoenzene), TPBi (1,3,5-tris(N-phenyl-en-zimidzol-2-yl)enzene), PCDTBT (poly(n-9 -heptdecnyl-2,7-crzole-lt-5,5- (4,7-di-2-thienyl-2,1,3 -enzothidizole))) nd PC 71 BM ((6,6)-phenyl C71 utyric cid methyl ester) were purchsed from Luminescence Technology Corportion (Tiwn, Chin). C ws purchsed from Sigm-Aldrich (USA). Ag ws purchsed from ZhongNuo Advnced Mteril (Beijing, Chin) Technology Co., Ltd. All mterils for the friction of the OLEDs nd PSCs were used s received without ny tretment. Brrier lyer friction The dhesive nd elstomeric sustrte ws cut to the desired size (5 cm 5 cm), nd working region (.6 cm 5 cm) ws defined y plstic tpe. A metl stencil ws ttched onto the working region with the long xes prllel to ech other. A lyer of luminum (Al) film ws deposited onto the surfce of the elstomeric sustrte vi the metl stencil y therml evportion (Fig. 1). The thickness of the Al rrier lyer ws 5 nm. Then, the metl stencil ws removed from the sustrte nd periodic Al film ws otined s rrier lyer (Fig. 1). The regions of the dhesive nd elstomeric sustrte covered y the Al film lost viscidity. As shown in Fig. 1c, the sustrte ws pre-stretched, with the period of the Al rrier lyer incresed. SOLEDs friction Ultrthin OLEDs were fricted y stripping process 4. An Ir(BT) 2 (cc)-doped CBP film ws used s the emitting lyer. The detiled device structure ws Ag/ MoO 3 /NPB/CBP:Ir(BT) 2 (cc)/tpbi/c/ag, s shown in Supplementry Fig. S1. The free-stnding ultrthin OLED ws plced onto the surfce of roller nd then trnsferred to the pre-stretched elstomeric sustrte (Fig. 1d). During this process, onding ws limited to only the re regions of the sustrte, with no onding occurring t the Al rrier lyer regions. Finlly, in Fig. 1e, SOLEDs with periodic uckles were formed fter relesing the prestretched elstomeric sustrte. The originl length of the elstomeric sustrte ws 6 mm, which ws incresed to 18 mm fter stretching to 2% strin. During the uckle

3 Yin et l. Light: Science & Applictions (218) 7:35 Pge 3 of 8 Metl stencil Al film f Al film deposition vi metl stencil Elstomeric sustrte e Removing the metl stencil % strin 1 um 5 um d Pre-strin relesing nd stretchle electronic devices forming c g 1 um 2% strin 5 um Attching the ultrthin electronic devices on the elstomeric sustrte Prestretching the elstomeric sustrte Fig. 1 Schemtic digrm showing the friction process for the stretchle electronic devices. Depositing Al film on n elstomeric sustrte y therml evportion vi metl stencil. Removing the metl stencil from the elstomeric sustrte. c Pre-stretching the elstomeric sustrte. d Attching n ultrthin electronic device onto the elstomeric sustrte. e Relesing the pre-strined sustrte to form stretchle electronic devices. f, g SEM imges of the periodic Al film deposited onto the elstomeric sustrte efore nd fter stretching corresponding to nd c, respectively. Insets show enlrged SEM imges for the periodic Al film deposited onto the elstomeric sustrte efore nd fter stretching forming process shown in Fig. 1d, e, the length of the elstomeric sustrte contrcted to 9 mm. When restretching the devices, the lrgest tensile strin ws 1% ccording to the length increse from 9 to 18 mm. For the friction process of the SOLED rry, the stencil used for Al rrier lyer deposition contined period of 55 μm, of which the width of the open spces nd metl lines were 45 nd 1 μm, respectively, s shown in Supplementry Fig. S2. OLED stripes were precisely ttched onto the dhesive re regions of the dhesive to ensure overlp for the period of the OLED rry nd the Al rrier lyer. Friction of SPSCs Ultrthin PSCs were fricted y the sme stripping process s used for SOLEDs. NOA 63 film coted onto silicon slice ws first trnsferred into vcuum chmer to thermlly deposit n Ag cthode nd TPBi lyer. Then, solution of PCDTBT:PC 71 BM (1:4 w/w, polymer concentrtion of 25 mg ml 1 in 1,2-dichloroenzene) ws spin-coted top the TPBi lyer. The spin-coting speed ws 3 r.p.m. for hlf minute. The resulting film hd thickness of ~8 nm. The whole semi-finished device ws nneled on heting stge t 7 C for 6 min in glove ox filled with inert gs. Finlly, the smple ws trnsferred into the vcuum chmer gin to deposit the MoO 3, Au, nd Ag lyers. The ultrthin polymer solr cell ws peeled off from the silicon slice nd ttched onto the pre-stretched elstomeric sustrte. SPSCs with periodic uckles were formed fter relesing the sustrte. Chrcteriztion All SEM imges were tken y JEOL JSM-75F scnning electron microscope (SEM) (JEOL Ltd.). An XP- 2 stylus profilometer (Amios Technology, Inc.) ws utilized to mesure the thickness of the ultrthin NOA63 film. I L V chrcteristics for ll OLEDs were investigted y Keithley 24 source meter nd Photoreserch PR-655 spectrophotometer with n MS-75 nd SL-1 composite lens. PSCs nd SPSCs were chrcterized y Keithley 24 source meter under illumintion provided y solr simultor (AM 1.5 Glol spectrum, with light intensity of 1 mw cm 2 ). Results nd discussion The metl stencil is shown in Supplementry Fig. S3. The period of the ptterns is 4 μm, of which the widths of the open spce nd the metl line re 3 nd 1 μm, respectively. As shown in Fig. 1, the stencil semlessly contcted with the dhesive nd elstomeric sustrte. As result, the otined Al rrier lyer ws uniform nd showed the sme period s the stencil pttern s shown in

4 Yin et l. Light: Science & Applictions (218) 7:35 Pge 4 of 8 the SEM imge in Fig. 1f. After stretching the sustrte to 2% strin, the period of the Al rrier lyer chnged (Fig. 1g). In prticulr, its period incresed to 12 μm, of which the width of the metl stripe region nd the re region were ~9 nd 3 μm, respectively. The incresing proportion ws identicl to the tensile strin, which demonstrted tht the deposited thin Al film did not ffect the stretchility of the elstomeric sustrte. The uniform deformtion of the elstomeric sustrte ws eneficil for ordered uckle formtion. The inset of Fig. 1f shows the surfce morphology of the thermlly evported Al film for zoomed-in region. A lrge roughness nd msses of smll rndom wrinkles cn e oserved. The morphology of the metl films deposited y therml evportion is relted to the receiving sustrte mterils The Al film frctured to smll frgments fter eing stretched to 2% strin (inset of Fig. 1g). The frcture phenomenon ws lso oserved in Al films with different thicknesses, s shown in Supplementry Fig. S4. The width of the Al frgments nd their gps were ll smller thn 1 μm with vrious thicknesses. SOLEDs nd SPSCs sed on the stencil-pttern trnsferring process were fricted. Ultrthin OLEDs nd PSCs were otined y fricting devices on ultrthin polymer films. The totl thickness of the ultrthin devices ws ~3 μm, of which the polymer film thickness ws ~2.8 μm. Figure 2 shows the SOLEDs t different tensile strin. The ultrthin OLEDs only dhered to the periodic re regions nd ent ove the Al regions of the sustrte, s shown in Fig. 2. Periodic uckles within the whole ultrthin device were formed, which demonstrted effective control of the uckling process through the Al rrier lyer. With 2% pre-strin, the SOLEDs exhiited lrge tensile strin of 1%. The decresed stretchility ws due to incomplete contrcting of the elstomeric sustrte. The compressive stress of the elstomeric sustrte decresed grdully fter relesing the pre-strin. At the sme time, the smll-ending rdii resulted in lrge-ending stress, with corresponding lrge resistnce in the compressive direction, which hindered the elstomeric sustrte from solutely contrcting to its originl stte. The period of the uckles ws the sme s tht of the Al films t vrious stretched sttes. At the lrgest pplied tensile strin of 1%, the periodic uckles disppered. Figure 2 nd Supplementry Movie 1 show the operting SOLEDs in sttic nd dynmic sttes, respectively. Ir (BT) 2 (cc) ws used s the light-emitting mteril, with yellow emission relized. The right light-emission re grdully elongted with incresing tensile strin, which visully showed the stretchility of the SOLEDs. Periodic uckles nd the Al rrier lyer cn e clerly seen. The opertion of the SOLEDs in drk environment ws lso investigted, s shown in Fig. 3. Figure 3 shows lrgere SOLED contining nine periods of uckles t different strins. The visile periodic uckles slightly influence the uniformity of the emission oserved from the SOLED. Figure 3 (Supplementry Movie 2) shows n rry of five OLED pixels; this rry forms pttern of light nd drk stripes. The period of the rry ws the sme s tht of the uckles. Periodic uckles formed t lower strin nd light from ech pixel ws reflected y n djcent non-plnr metl node film, which mde ech pixel look wider. The synchroniztion of the periodic uckles nd the OLED rry revel the potentil pplictions for the SOLED in stretchle displys. The electroluminescence (EL) performnce of the SOLEDs ws mesured t different stretched sttes, s shown in Fig. 4,. The EL performnce of the SOLEDs ws excellent, stle t different tensile strin nd comprle to tht of the plnr device. The mximum current efficiency t % nd 1% tensile strin ws 71 nd 73 cd A 1, respectively, with vrition of only 2.8%. Supplementry Figure S5 shows the EL spectr mesured t different strin vlues. A redshift in the spectrl curves ws oserved with incresing tensile strin, which % 5 um 5 um 5 um 5% 1% % 5% 1% 2 mm Fig. 2 Demonstrtion of SOLEDs. SEM imges () nd photogrphs () of the SOLEDs t %, 5%, nd 1% tensile strin, respectively

5 Yin et l. Light: Science & Applictions (218)7:35 Pge 5 of 8 % 5% 1% 5% 1% 2 mm % 2 mm Fig. 3 Photogrphs of the SOLEDs in drk environment. A lrge-re SOLED t %, 5%, nd 1% tensile stin. An rry of five OLED pixels t %, 5%, nd 1% tensile strin % 25% 5% 75% 1% Plnr k 1k Voltge (V) 7 Currennt efficiency (cd A 1) 35 Luminnce (cd m 2) Current density (ma cm 2) 7 6 d % 25% 5% 75% 1% Plnr c Voltge (V) Normlized vlues Normlized vlues Normlized luminnce.4 Normlized current efficiency ,.8.6 Normlized luminnce Normlized current efficiency.4.2 2% 1. 15, 2, Numer of stretch-relese cycles. 6% Numer of stretch-relese cycles Fig. 4 EL performnce of SOLEDs. Current density-luminnce-voltge chrcteristic curves () nd current efficiency-voltge chrcteristic curves () for the SOLEDs. Device performnce under cyclic stretching test etween nd 2% strin (c) nd etween nd 6% strin (d) results from the microcvity effect in SOLEDs41. The slight redshift (~5 nm) ws in greement with the stle current efficiency. The ove results indicte tht the periodic uckling profile introduced into the SOLEDs leds to negligile deteriortion of the device performnce. The mechnicl stility of the SOLEDs ws exmined y cycliclly stretching the devices etween vrying strin vlues. The SOLED ws mesured t % strin fter every 5 stretch-relese cycles in ir without ny encpsultion. The driving voltge ws 5.5 V. Figure 4c, d shows the EL performnce of the SOLEDs. The luminnce incresed

6 Yin et l. Light: Science & Applictions (218) 7:35 Pge 6 of 8 y ~2% during the first 3 cycles of cyclic stretching nd ecme stle in the following test etween nd 2% strin (Fig. 4c). Similrly, the luminnce of SOLEDs slightly incresed during cyclic stretching etween nd 6% strin, s shown in Fig. 4d. The current efficiency exhiited slight vrition of 2%. As seen from Supplementry Figs. S6 nd S7, the normlized current density for the SOLEDs under the cyclic stretching test showed similr increse during the initil 3 cycles. A possile origin for the incresed current density for the initil 3 stretch-relese cycles is the compression effect in smll-molecule semiconductor films, s shown in Supplementry Fig. S8 6,61. The SOLED ws found to e mechniclly roust, s demonstrted y the cyclic stretching tests. The mechnicl roustness ws ttriuted to the ordered uckles. The Al films degrded little nd mintined good dhesion with the elstomeric sustrte fter 2, cycles of cyclic stretching (Supplementry Fig. S9). The SOLEDs retined n ordered uckling profile without distortion during the stretchrelese process (Supplementry Fig. S1). Any defects in the device cn e spred nd mplified fter thousnds of stretch-relese cycles, resulting in degrded performnce. The smllest ending rdius for the periodic uckles ws ~1 μm t % strin, s shown in Fig. 2. The ending strin determined y the ending rdius nd thickness of the ultrthin OLEDs ws only ~.68% for the metllic node 4. Therefore, the ending deformtion due to the periodic uckles did not cuse ovious mechnicl nd electricl dmge to the SOLEDs, nd they could operte stly nd efficiently with such lrge-ending strin during cyclic stretching. Stretchle solr cells re n importnt memer of stretchle orgnic optoelectronics. Efficient nd mechniclly roust stretchle solr cells re the est cndidtes for electric power suppliers in stretchle electronic system integrted with other stretchle electronic devices. However, previously reported stretchle solr cells with rndom uckles could only withstnd tens to hundreds of cyclic stretches, which hindered their use for commercil pplictions 11,34,39,43. Here, we demonstrted mechniclly roust SPSCs sed on the use of simple stencil-pttern trnsferring technology. This pper presents the first report of SPSCs with periodic uckling structures. The device structure of n ultrthin polymer solr cell is shown in Supplementry Fig. S11. A polymerfullerene derivtive PCDTBT:PC 71 BM lend ws used s light sorer. The SPSCs were lso fricted y following the steps shown in Fig. 1 e. Periodic uckles were formed, with lrge tensile strin of up to 1%, s shown in Supplementry Fig. S12. The J V chrcteristic curve for plnr solr cell is shown in Fig. 5. Its power conversion efficiency ws 5.1%, with n open-circuit voltge (V OC ) of.78 V, short-circuit current density (J SC )of Current density (ma cm 2 ) V oc =.78 V J sc = 12 ma cm 2 FF = 54% PCE = 5.1% Voltge (V) Current (ma) % 1% 2% 3% 4% 5% 6% 7% 8% 9% 1% Voltge (V) c Normlized vlues V oc I sc FF d Normlized vlues Power.6 V oc.4 I sc.2 Power , Strin (%) Numer of stretch-relese cycles 1..8 FF Fig. 5 Chrcteriztion of SPSCs. J V chrcteristic curve for plnr polymer solr cell. J V chrcteristic curves for the SPSCs t different strin vlues. c Prmeters for the SPSCs t different strin vlues. d Device performnce under cyclic stretching test etween nd 2% strin

7 Yin et l. Light: Science & Applictions (218) 7:35 Pge 7 of 8 12 ma cm 2, nd fill fctors (FFs) of 54%, which re comprle with the est reported polymer solr cells sed on PCDTBT:PC 71 BM 62,63. The I V chrcteristics for the SPSCs were mesured for vrying tensile strin vlues, s shown in Fig. 5. The devices worked functionlly t ech stretched stte. The normlized vlues for V OC, I SC, FF, nd output power t different tensile strin re summrized in Fig. 5c. The output power ws defined s Output power ¼ V OC I SC FF ð1þ V OC nd FF chnged little, while I SC nd the output power incresed lmost linerly with incresing tensile strin. This outcome ws ttriuted to the incresed light incident re, with tensile strin incresing despite the prcticl device re not chnging. At the sme time, the linerly incresed I SC indicted tht the periodic uckles hd nerly no influence on the light sorption in the SPSCs. The mechnicl stility of the SPSCs ws exmined y cycliclly stretching the devices etween nd 2% tensile strin, s shown in Fig. 5d. The I V chrcteristics were mesured t % strin fter every 5 stretch-relese cycles. The SPSCs could survive 12, stretch-relese cycles; this vlue is two orders of mgnitude higher thn tht reported in previous results otined for rndomuckle-sed SPSCs 11,34,43. To the est of our knowledge, our mechnicl stility for SPSCs is the highest reported to dte. It should e noted tht the degrdtion in V OC nd FF ws quite smll. The stle FF indicted tht no lrge dmge due to crcks or delmintion ws introduced into the PSCs during the cycling, so s not to ffect the conductivity nd series resistnce. The clerly fluctunt I SC might e cused y the fluctunt incident re for the SPSCs t % strin under ech mesurement. The elstomeric sustrte is visco-elstic. Thus, it would tke some time to contrct to % strin stte solutely, especilly under continuously cyclic stretching. Therefore, smll vrition exists in the incident re for ech mesurement during the cyclic stretching test, leding to the oserved fluctution in I SC. Conclusions A simple nd universl stencil-pttern trnsferring technology ws pplied to stretchle orgnic optoelectronic devices, resulting in the demonstrtion of highperformnce SOLEDs nd SPSCs with periodic uckles. A periodic Al rrier lyer tht ws deposited onto elstomeric sustrtes y stencil pttern plyed the role of forming periodic uckles for ultrthin optoelectronic devices. The SOLEDs nd SPSCs oth exhiited the highest mechnicl roustness reported to dte; notly, the SPSCs showed n improvement of two orders of mgnitude. Stretchility, efficiency, mechnicl stility, nd production cost re key fctors for prcticl pplictions of stretchle optoelectronics. The simple nd universl stencil-pttern trnsferring technology used in this work provides solution for low-cost nd highperformnce stretchle optoelectronic devices nd demonstrtes potentil for commercil development of stretchle electronics nd optoelectronics. Acknowledgements This work ws supported y the Ntionl Key Reserch nd Development Progrm of Chin (project no. 217YFB445) nd the Ntionl Nture Science Foundtion of Chin (NSFC) (grnt nos , , nd ). Conflict of interest The uthors declre tht they hve no conflict of interest. Supplementry informtion is ville for this pper t /s x. Received: 21 Decemer 217 Revised: 12 My 218 Accepted: 18 My 218 Accepted rticle preview online: 6 June 218 References 1. Bde, S. G. R. et l. Stretchle light-emitting diodes with orgnometlhlide-perovskite-polymer composite emitters. Adv. Mter. 29, (217). 2. Wng, J. X. et l. Extremely stretchle electroluminescent devices with ionic conductors. Adv. Mter. 28, (216). 3. Lrson, C. et l. 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