Supporting Information

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Copyright WILEY-VCH Verlg GmH & Co. KGA, 69469 Weinheim, Germny, 2018. Supporting Informtion for Glol Chllenges, DOI: 10.1002/gch2.

1 Copyright WILEY-VCH Verlg GmH & Co. KGA, Weinheim, Germny, Supporting Informtion for Glol Chllenges, DOI: /gch Holey MoS 2 Nnosheets with Photoctlytic Metl Rich Edges y Amient Electrospry Deposition for Solr Wter Disinfection Depnjn Srkr, Biswjit Mondl, Anirn Som, Swthy Jkk Rvindrn, Sourv Knti Jn, C. K. Mnju, nd Thlppil Prdeep*

2 Supporting Informtion Holey MoS 2 Nnosheets with Photoctlytic Metl Rich Edges y Amient Electrospry Deposition for Solr Wter Disinfection Depnjn Srkr, Biswjit Mondl, Anirn Som, Swthy Jkk Rvindrn, Sourv Knti Jn, C. K. Mnju nd Thlppil Prdeep* EXPERIMENTAL SECTION All the commercilly ville chemicls were used s is, without further purifiction. Silver cette (AgOAc), molydenum disulfide (MoS 2 ), 1.6 M n-utyllithium in hexne nd the solvent, hexne were purchsed from Sigm Aldrich, Indi. Synthesis of MoS 2 NS. Chemicl exfolition method ws used to synthesize MoS 2 NSs from MoS 2 powder. [1] 300 mg of MoS 2 powder ws tken in round ottom flsk, under n rgon tmosphere, nd 3 ml of 1.6 M n-utyllithium ws dded. The resulting solution ws stirred for 2 dys under the sme conditions. Then the resulting lithium interclted product ws wshed repetedly with hexne, to remove excess rectnts, followed y the ddition of 100 ml of distilled wter. The produced ws sonicted in th sonictor for 1 h. This queous dispersion of MoS 2 NSs ws centrifuged t speed of rpm to remove un-exfolited MoS 2. The qulity of the synthesized MoS 2 NSs ws checked using electron microscopy, UV- Vis nd Rmn spectroscopy. The concentrtion of MoS 2 dispersion ws determined using inductively coupled plsm mss spectrometry (ICP MS). Electrospry deposition on MoS 2 NSs. For electrospry deposition, home uilt nnoelectrospry ioniztion (nesi) source ws used. The nesi source ws mde y pulling orosilicte glss cpillry (0.86 mm ID nd 1.5 mm OD) into two, using micropipette puller (Sutter Instruments, U.S.A.). Ech tip, fter pulling, ws checked using n opticl microscope to ensure the size nd qulity of the cut. Tips with n opening of µm were 1

3 used for ll the deposition experiments. 10 mm queous solution of AgOAc ws filled in the nesi tips using micro injector pipette tip nd Pt wire ws inserted into the solution, mking n electrode for high voltge connection. For electrospry deposition on MoS 2 NSs, n queous suspension of 3.7 mm (in terms of Mo) MoS 2 NS ws tken in n Eppendorf vil nd the Ag + ions generted y the nesi source ws guided towrds it. The distnce etween the tip of the nesi source nd the surfce of the MoS 2 solution ws optimized to e 10 mm. No chnges in the size or nture of the holes were oserved with chnge in the distnce etween the tip nd the deposition surfce provided the mount of the ions were constnt. The wter MoS 2 suspension ws grounded through picommeter using copper strip. The deposition current ws vried from na for different experiments. Detils of the cteri nd virus used for disinfection rection. Escherichi coli nd MS2 cteriophge, the surrogtes for wter orne pthogens (cteri nd viruses, respectively) were used for ntimicroil testing. Sline wter condition ws used for ll the nticteril nd ntivirl testing. A fresh single colony of the Escherichi coli (ATCC 10536) pre-grown on Luri Bertni (LB) gr ws used s the inoculum nd cell suspensions in LB roth were llowed to grow t 37 C to lte exponentil phse with finl opticl density (600 nm) of 1. This ws used s the input for nticteril experiments. In the cse of ntivirl testing, F- specific cteriophge MS2 (ATCC B1) ws cultured using E. coli host C-3000 (ATCC 15597) in the logrithmic phse. Purified virus ws used s input for ntivirl experiments. Electrochemicl mesurements. Both cyclic voltmmetry (CV) nd liner sweep voltmmetry (LSV) were mesured y n electrochemicl nlyzer (CHI 600A) with conventionl three-electrode configurtion dopted with ulk Au (111) electrode s the working electrode, silver/silver chloride (Ag/AgCl) s the reference electrode nd Pt wire s the counter electrode. Prior to ny electrochemicl mesurement, Au electrode ws clened mnully with two different micro 2

4 polishing powders of Al 2 O 3 (prticle size ~ 0.3 µm nd 0.05 µm). All the electrochemicl mesurements were performed t room temperture nd in phosphte uffered sline (Merck Indi Pvt. Ltd) solution of ph~ 7.3. Drk field fluorescence microscopic nlysis. Fluorescence microscopy imging ws performed using Cytoviv microscopy system. For smple preprtion, LIVE/DEAD Bclight TM cteril viility kit (Moleculr Proes, Eugene, OR) ws used. At ech time point, 1 ml of the smple (holey MoS 2 nnosheet treted nd control cteri) ws mixed with 2 µl of PI-SYTO 9 mix (1:1) nd incuted in drk for 15 min. Aout μl smple ws spotted on 1 mm thick ultrsoniclly clened glss slide (SCHOTT) nd it ws covered with mm thick clened glss cover slip (SCHOTT). Imging ws performed using 100X oil (Crgille) immersion ojective. 107 Ag Ag + [ 107 Ag(H 2 O)] + [ 109 Ag(H 2 O)] m/z Figure S1. nesi of AgOAc. Mss spectrum collected from the nesi of AgOAc. The Mo 3d region of prent mterils in XPS showed two peks t nd t ev inding energy corresponding to 3d 5/2 nd 3d 3/2 of Mo(IV). But when the XPS spectrum fter the electrospry of Ag + ions ws tken, lue shift of 0.3 ev ws seen due to the decrese in 3

5 Intensity (.u) numer of sulphide ions (ecuse of the rection with silver). The emergence of two new peks is ttriuted to the formtion of Mo(VI)O 4 2- (s result of the Mo sites lost due to rection). [20] Before silver spry Mo c Before silver spry S 3d 5/2 2p 3/2 S 2s 3d 3/2 2p 1/ After silver spry d After silver spry 3d 5/2 3d 3/2 2p 3/2 2p 1/2 S 2s 3d 5/2 3d 3/ Binding energy (ev) Figure S2. (-) correspond to the XPS spectr in the Mo 3d region efore nd fter the electrospry of silver, respectively. (c-d) XPS spectr in the S 2p region efore nd fter the electrospry of silver, respectively. 4

Figure S3. Chrcteriztion of MoS 2 NSs. () TEM imge of s-synthesized MoS 2 nnosheet.

6 Intensity (.u) Asornce (.u) 0.5 µm c MoS 2 Bulk d 410 nm MoS 2 NS 620 nm E 2g A 1g 672 nm Rmn Shift (cm -1 ) Wvelength (nm) Figure S3. Chrcteriztion of MoS 2 NSs. () TEM imge of s-synthesized MoS 2 nnosheet. () HAADF TEM imge of () MoS 2 nnosheet showing tht there re no defects in it. (c) Rmn spectrum collected from the MoS 2 nnosheet nd ulk MoS 2. The pek difference (~18 cm -1 ) of E 2g nd A 1g for MoS 2 NSs suggests tht the sheets re one lyer thick. (d) UV- Vis spectrum collected from suspension of MoS 2 NSs. 5

() TEM imge of the MoS 2 nnosheet showing

Inset shows TEM energy dispersive spectrum

22 nm suggest tht the formed nnoprticles

Input (10 7 /ml) MoS 2 NSs (10 5 /ml) c d

(with Bcillus sutilis cteri) of MoS 2 NSs

7 100 nm 2 nm kev Figure S4. Chrcteriztion of Ag 2 S NPs. () TEM imge of the MoS 2 nnosheet showing the complete rection of it. Inset shows TEM energy dispersive spectrum of Ag 2 S prticles. () HRTEM imge of n Ag 2 S prticle. The d(112) nd d(031) plnes of 0.24 nm nd 0.22 nm suggest tht the formed nnoprticles re the cnthite phse of Ag 2 S. Input (10 7 /ml) MoS 2 NSs (10 5 /ml) c d Holey MoS 2 (10 4 /ml) Figure S5. Anticteril performnce of holey MoS 2. (-c) Photogrph of the nticteril ctivity (with Bcillus sutilis cteri) of MoS 2 NSs shown in () nd with holey MoS 2 shown in (c). () Input cteril concentrtion nd (d) comprison of nticteril ctivity of MoS 2 NSs nd holey MoS 2. 6

Current (µa) Input (10 7 /ml) Bulk MoS 2 2 (10 6 /ml) MoS 2 NSs (10 4 /ml) c Holey MoS Holey MoS 2 (0/mL) 2

(-d) Photogrph of ntivirl (cteriophge MS2) ctivity of () ulk MoS 2, (c) MoS 2 NSs nd (d) holey MoS 2.

4 0.0 0.2 0.4 0.6 0.8 1.0 1.2 0.0 0.2 0.4 0.6 9 0.8 4 c 6 3 0 0.6 0.4 0.2 0.0-0.2 1.0 0.8 0.6 0.4 (I) (II) PBS 1 mm 5 mm 10 mm 20 mm 0.

Ag/AgCl) Figure S7. CV trces of Au electrode in different electrolytes.

8 V. Inset of c shows the concentrtion-dependent liner sweep voltmmetry (LSV) trces scnned up to 0.9 V.

8 Current (µa) Input (10 7 /ml) Bulk MoS 2 2 (10 6 /ml) MoS 2 NSs (10 4 /ml) c Holey MoS Holey MoS 2 (0/mL) 2 (10 6 /ml) d Figure S6. Antivirl ctivity of holey MoS 2. (-d) Photogrph of ntivirl (cteriophge MS2) ctivity of () ulk MoS 2, (c) MoS 2 NSs nd (d) holey MoS 2. Expnded views of the petri dishes re shown s insets PBS PBS c (I) (II) PBS 1 mm 5 mm 10 mm 20 mm d NCl N SO Potentil (V, vs. Ag/AgCl) Figure S7. CV trces of Au electrode in different electrolytes. CV trces of gold in () PBS; (c) NCl; (d) N 2 SO 4, respectively. () CV trce of gold in PBS scnned up to 0.8 V. Inset of c shows the concentrtion-dependent liner sweep voltmmetry (LSV) trces scnned up to 0.9 V. The CV profile of Au (Figure S7) mesured in PBS exhiits n oxidtion pek t V nd reduction pek t V. These were not seen in the CV mesured up to +0.7 V 7

9 (Figure S7) confirming tht the oxidtion pek t 0.95 V ws coupled with the reduction pek t V. These were ttriuted to the rection, Au + 4Cl - = AuCl e -. Although these peks were not seen in Figure S7, there ws smll oxidtion pek t V, which is lso seen in Figure S7. In order to understnd the origin of this smll pek, we performed the sme CV mesurement (scnned up to +1.2 V) in NCl solution (Figure S7c) nd the pek ppered gin t V long with the other peks. However, when we performed the sme experiment in N 2 SO 4, the pek round V ws not seen (Figure S7d). To ssign the rod pek round V, we performed liner sweep voltmmetry (LSV) up to +0.9 V with different concentrtions of NCl (spectr shown in the inset of Figure S7c). Seemingly, the single pek oserved t V in Figure S7c ws ctully composed of two peks s shown in the inset of the sme figure. At lower concentrtions of NCl, the two peks were well seprted from ech other nd the pek seprtion of these two ecome nrrower s concentrtion of NCl ws incresed. For etter clrity, we mrked these peks s I nd II. First pek I ws due to Cl - dsorption on Au surfce nd consecutive oxidtion of Au y the rection, Au (surfce) Cl - = AuCl (surfce) + e - (pek II ). [2] At lower concentrtion of NCl (1 mm), coverge of Cl - ws lower nd correspondingly Au oxidtion ws poor. However, s NCl concentrtion ws incresed, current strted incresing. Finlly, mximum current ws seen t 20 mm NCl which ws due to higher Cl - coverge nd therefore, mximum oxidtion. Beyond 20 mm of NCl concentrtion, no further chnge of pek current ws oserved. As Diffusion H 2 O 2 comes in contct with the electrode ( H 2O H 2( ulk ) 2O2( electrode ) ) it gets oxidized (H 2 O 2 = 2H + + O 2 +2e - ) t the sme potentil. Current ( A) Current ( A) Blnk mm Potentil (V, Ag/AgCl) Potentil (V, vs. Ag/Cl) Figure S8. CV of externlly dded H 2 O 2. () CV trces of control experiment performed with externlly dded H 2 O 2 with different concentrtions, in PBS. () Mgnified version of the mrked re of Figure S8. 8

10 Current (A) 1.40E E h, 10 min 1 h, 20 min 1.00E E E E E E Potentil (V, vs. Ag/AgCl) Figure S9. Liner sweep voltmmetry (LSV) profile of MoS 2 NS suspensions with different time of sprying of Ag +. LSV spectrum MoS 2 NSs suspension fter 10 nd 20 min of Ag + deposition nd 1h of visile light irrdition. Smples Concentrtion of H 2 O 2 (µm) MoS 2 NSs without hole (1 h) 0.43 MoS 2 NSs without hole (2 h) 0.63 Holey MoS 2 NSs (1 h) 0.69 Holey MoS 2 NSs (1 h) 1.54 Tle S1. Quntifiction of H 2 O 2 concentrtion generted from holey MoS 2 using clirtion curves. 9

11 Treted with smple Treted with H 2 O 2 3 µm 3 µm Figure S10. Imging of ded cteri. (-) SEM imges of the cteri (E. coli) fter the tretment with the smple nd H 2 O 2, respectively. In oth the cses, similr cell dmge ws oserved. Input After 2 cycles c After 4 cycles d After 5 cycles Figure S11. Photogrphs of the experiment performed with the prototype. () Input (contminted wter), cteri count () fter 2 cycles, (c) fter 4 cycles nd (d) fter 5 cycles. 10

Asornce 0.60 MoS 2 0.45 On lumin 0.30 0.15 0.00 400 600 800 1000 Wvelength (nm) Smple MoS 2 NSs Mo concentrtion (pp) 0.08 pp Figure S12.

() UV-Vis spectr of MoS 2 NSs (lck) nd the superntnt (red) tken from MoS 2 -dsored lumin@wter. Negligile leching ws oserved.

12 Asornce 0.60 MoS On lumin Wvelength (nm) Smple MoS 2 NSs Mo concentrtion (pp) 0.08 pp Figure S12. No leching of MoS 2 from MoS 2 -dsored lumin. () UV-Vis spectr of MoS 2 NSs (lck) nd the superntnt (red) tken from MoS 2 -dsored lumin@wter. Negligile leching ws oserved. () ICP MS nlysis of the superntnt showed negligile Mo concentrtion. Figure S13. E. coli contminted wter ws pssed through column pcked with only lumin. Photogrph of () Input (contminted wter) nd () output. No disinfection ws oserved. 11

13 References [1] ) L. Yuwen, H. Yu, X. Yng, J. Zhou, Q. Zhng, Y. Zhng, Z. Luo, S. Su, L. Wng, Chem. Commun. (Cmridge, U. K.) 2016, 52, ; ) L. Yuwen, F. Xu, B. Xue, Z. Luo, Q. Zhng, B. Bo, S. Su, L. Weng, W. Hung, L. Wng, Nnoscle 2014, 6, ; c) C. N. R. Ro, Rmkrishn Mtte, S. S. H., U. Mitr, Angew. Chem., Int. Ed. 2013, 52, [2] ) L. Aldous, D. S. Silvester, C. Villgrn, W. R. Pitner, R. G. Compton, L. M. Cristin, C. Hrdcre, New Journl of Chemistry 2006, 30, ; ) Z. Shi, J. Lipkowski, J. Electronl. Chem. 1996, 403,

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