BUSCADOR RECOLECTA

6 pages. -- Table 1. Composition of different glass types used as substrates. -- Fig. 1. Comparison of Ψ and Δ spectra for standard sample step and poled region, together with corresponding fits. -- Fig. 2. Au NPs: poled and step region ε2 (a) and corresponding SEM micrographs (b, c). -- Fig. 3. The effect of plasma cleaning: comparison of sample cleaned with plasma upon GP and prior to coating (left) and a standard sample (right). -- Fig. 4 Difference of ε2 for Ag NPs containing layers over poled and step region for Cr containing sample. -- Fig. 5. SEM micrographs: transition between step (upper part) and poled region (lower part) of the sample with higher Ag concentration in the coating (a), protrusion of crystallites from the coating (b), out diffused crystallites (c) and their clustering (d). EDS of step region: at the site of the crystallite (e) and a site next to it (f). -- Fig. 6. The sample coated immediately after poling in vacuum: comparison of Ψ and Δ spectra for step and poled region (a) and b), respectively). -- Fig. 7. Transition between step and poled region of the sample coated immediately after poling in vacuum: from step region with out-diffused Na crystallites to the poled, crystallites free region confirming absence of IE., Peer reviewed

22 pages. -- PDF file includes: Structural characterization. -- Electrochemical Measurements. -- Faradaic efficiency (FE). -- Ionic strength compensation. -- Hypochlorite titration analysis. -- DFT Computational method. -- Figure S1 a-f) SEM images of the Mo-Co precursor. -- Figure S2 a-f) SEM images of MoN-Co2N. -- Figure S3. a-c) SEM images and d) EDS result of MoN-Co2N. -- Figure S4. a-f) TEM images of MoN-Co2N. -- Figure S5. a-c) TEM images and d-f) HAADF-STEM images of MoN-Co2N. -- Figure S6. TEM and HRTEM images of the MoN-Co2N. -- Figure S7. EELS chemical composition maps of MoN-Co2N obtained from the red squared area of the STEM micrograph. -- Figure S8. XRD patterns of MoN-Co2N, Mo-Co2N and CoxN compared with reference patterns of Co, Co4N, Co2N and MoN. -- Figure S9. a-c) SEM images and d) EDS result of Mo-Co2N. -- Figure S10. a-c) SEM images and d) EDS result of CoxN. -- Figure S11. Pore size distribution plot for MoN-Co2N and CoxN. -- Figure S12. Cyclic voltammograms for a) MoN-Co2N; b) Mo-Co2N; c) CoxN and d) Mo-Co precursors and e) IrO2 in the non-faradaic region of 1.12-1.22 V vs. RHE at various scan rates. -- Figure 13. a) N and b) Co partial and c) Total Density of states for Co2N and MoN-Co2N. -- Figure S14. The evolutions of local structural configurations for illustrating OER process of Co2N. (* represents the active site). -- Figure S15. Photograph of flasks containing seawater after adding KOH (left) and before adding KOH (right). -- Figure S16. Overall water/seawater splitting performance of MoN-Co2N ‖ MoN-Co2N and Pt/C ‖ IrO2 cells in 1 M KOH, 1 M KOH seawater, and untreated seawater. -- Figure S17. Overall water splitting performance of MoN-Co2N ‖ MoN-Co2N and Pt/C ‖ IrO2 cells in 1 M KOH seawater with and without ionic strength compensation. -- Figure S18. a) Digital photographs of the reaction and reference solutions for the iodometric titration, showing the absence of ClO− production in theº former case. b) Measured (dots) and theoretical (solid line) gaseous products by the two-electrode electrolyzer at a current of 50 mA cm-2 in 1 M KOH seawater. -- Figure S19. High-resolution XPS spectra of a) N 1s, b) Co 2p, c) Mo 3d for MoN-Co2N and MoN-Co2N after long-term reaction. -- Figure S20. a-b) TEM images, c-d) HAADF-STEM images, e-f) HRTEM of MoN-Co2N after long time reaction. -- Figure S21. EELS chemical composition maps of MoN-Co2N after long time reaction obtained from the red squared area of the STEM micrograph. Individual C K-edge at 284 eV (orange), N K-edge at 401 eV (blue), Co L2,3-edges at 779 eV (red) and Mo M4,5-edges at 227 eV (green) and composites of Co-N and Mo-N. -- Table S1. Comparison of OER activity of MoN-Co2N with recently reported nitride electrocatalysts in 1.0 M KOH electrolyte. -- Table S2. Cdl and ECSAs of various catalysts. -- Table S3. Comparison of HER performance of MoN-Co2N with recently reported nitride electrocatalysts in 1.0 M KOH electrolyte. -- Table S4 Comparison of the overall water splitting of MoN-Co2N with previously reported electrocatalysts., The development of cost-effective bifunctional catalysts for water electrolysis is both a crucial necessity and an exciting scientific challenge. Herein, a simple approach based on a metal–organic framework sacrificial template to preparing cobalt molybdenum nitride supported on nitrogen-doped carbon nanosheets is reported. The porous structure of produced composite enables fast reaction kinetics, enhanced stability, and high corrosion resistance in critical seawater conditions. The cobalt molybdenum nitride-based electrocatalyst is tested toward both oxygen evolution reaction and hydrogen evolution reaction half-reactions using the seawater electrolyte, providing excellent performances that are rationalized using density functional theory. Subsequently, the nitride composite is tested as a bifunctional catalyst for the overall splitting of KOH-treated seawater from the Mediterranean Sea. The assembled system requires overpotentials of just 1.70 V to achieve a current density of 100 mA cm–2 in 1 M KOH seawater and continuously works for over 62 h. This work demonstrates the potential of transition-metal nitrides for seawater splitting and represents a step forward toward the cost-effective implementation of this technology., Peer reviewed

11 pages. -- Figure S1. SEM image and EDS spectrum of the as-synthesized NiS NPs. -- Figure S2. NiS NPs: (a) XPS survey spectrum. (b-c) Corresponding Ni 2p3/2, and S 2p high resolution XPS spectra. -- Figure S3. Ni NPs: (a) XRD pattern. (b) Representative TEM micrograph and the corresponding size distribution. -- Figure S4. CV curves for the monometallic Ni NPs based electrode in 1 M KOH with the presence of 1 M methanol or ethanol in alkaline media at a scan rate of 50 mV s 1. -- Table S1. Fitting parameters for the Nyquist curve at 1.5 V in 1.0 M KOH with and without 1.0 M m ethanol or ethanol. -- Figure S5. Electrochemical performance dependence on alcohol concentration for Ni-based electrode in 1 M KOH electrolyte. -- Figure S6. Electrochemical activity of Ni-based electrode in 1 M KOH. -- Figure S 7 . (a) CV curves in the potential range of 0.9 1. 6 V at different scan rates . (b) Linear fitting between the peak current and scan rates from 10 to 50 mV s 1 . (c) Linear fitting between the peak current and square root of scan rates from 60 to 100 mV s 1. -- Table S2. Comparison of the alcohols oxidation performance between this work and previously reported electrocatalysts with a similar system. -- Figure S8. (a) CA test towards MOR and EOR on NiS NPs electrode over 10,000 s testing period in 1 M KOH at 1.6 V. (b) IC curve of the solution at the end of CA testing. -- Figure S9. (a) Survey XPS spectrum of the NiS-based electrode after 10,000 s testing period in 1 M KOH and 1 M ethanol at 1.6 V. (b) High-resolution Ni 2p XPS spectrum. (c) High-resolution S 2pXPS spectrum. -- Figure S10. (a) Optimized structural model of NiOOH SO 4 (b) DOS of Ni OOH and Ni OOH SO 4 regarding the Ni 3d orbitals., The electrocatalytic oxidation of alcohols is a potentially cost-effective strategy for the synthesis of valuable chemicals at the anode while simultaneously generating hydrogen at the cathode. For this approach to become commercially viable, high-activity, low-cost, and stable catalysts need to be developed. Herein, we demonstrate an electrocatalyst based on earth-abundant nickel and sulfur elements. Experimental investigations reveal the produced NiS displays excellent electrocatalytic performance associated with a higher electrochemical surface area (ECSA) and the presence of sulfate ions on the formed NiOOH surface in basic media. The current densities reached for the oxidation of ethanol and methanol at 1.6 V vs reversible hydrogen electrode (RHE) are up to 175.5 and 145.1 mA cm–2, respectively. At these high current densities, the Faradaic efficiency of methanol to formate conversion is 98% and that of ethanol to acetate is 81%. Density functional theory calculations demonstrate the presence of the generated sulfate groups to modify the electronic properties of the NiOOH surface, improving electroconductivity and electron transfer. Besides, calculations are used to determine the reaction energy barriers, revealing the dehydrogenation of ethoxy groups to be more favorable than that of methoxy on the catalyst surface, which explains the highest current densities obtained for ethanol oxidation., Peer reviewed

11 pages. -- Fig. S1. Extra structure characterization of the Pd2Ga NRs. (a,b) HRTEMmicrographand the corresponding indexed power spectrum observed along the corresponding[001] (a) and [342] (b) zone axis of the orthorhombic Pnma Pd2Ga structure. (c) STEM-EELS elemental composition maps. -- Fig. S2. XRD pattern of as-synthesized Pd2Ga using 0.2 mmol of Pd(acac)2 and0.1mmol of Ga(acac)3 in the reaction. -- Fig. S3. SEM-EDS spectrum of Pd2Ga NRs. -- Fig. S4. (a-c) CV curves of Pd2Ga/C (a), Pd/C (b) and Pt/C (c) catalysts in 0.5MKOH with a scan rate of 20, 40, 60, 80 and 100 mV s-1. (d) Linear fit of the current density at 0.156 V as a function of scan rate from 20 to 100 mV s-1. -- Fig. S5. Nyquist plots of the catalysts at 0.8 V vs. RHE in 0.5 MKOHwith 0.5Methanol solution. -- Fig. S6. Comparison of the specific and mass activity of Pd2Ga/C, Pd/Cand Pt/Ccatalysts after 12 h CA measurements. -- Fig. S7. EOR CA curves of Pd2Ga catalyst reactivated by cycling every 1000 s inathree-electrode system with 0.5 M KOH and 0.5 M ethanol as electrolyte. -- Fig. S8. (a) 1H NMR analysis of the electrolyte before and after CA measurement. (b) 1H NMR analysis of acetic acid added in KOH and KOH + ethanol solution. -- Fig. S9. Potential-time curves of the Pd2Ga/C catalyst at current densities of 10mAcm-2 in 0.5 M KOH with ethanol solution. -- Fig. S10. Comparison of the current density of Pd2Ga/C, Pd/C and Pt/C catalysts after 15 h CA measurements in the two-electrode coupled system. -- Fig. S11. XRD Pattern (a) and TEM images of Pd2Ga/C in cathode (b) and anode (c) of the two-electrode electrolyzer after long-term stability measurement. -- Fig. S12. crystal structural models of Pd (111) and Pd2Ga (211). -- Fig. S13. DFT calculated models of Pd (a) and Pd2Ga (b) active sites with adsorbedreactive species from different EOR reaction states. -- Fig. S14. (a) CV curves of the catalysts in 0.5 M H2SO4 with 0.5 Methanol solution. (b) Polarization curves of catalysts in 0.5 M H2SO4 with 0.5 Methanol solution. (c) LSV curves of the assembled cells in 0.5 M H2SO4 with 0.5 Methanol solution. (d) CA measurements of the assembled cells at 1.0 V in 0.5 M H2SO4 with 0.5 Methanol solution. -- Fig. S15. DFT calculated models of OH- adsorbed on different sites of Pd2Ga (211) surface. -- Table S1. Comparison of specific activity, mass activity and stability of Pd- or Pt-based catalysts for EOR in alkaline media., Peer reviewed

6 pages. -- Figure S1. Pb 4f and S 2p high resolution XPS spectra obtained from the PbS nanoparticles. -- Figure S2. XRD patterns of PbS nanoparticles with and without H2-reducing treatment. -- Figure S3. SEM images and EDX spectra of a) PbS nanoparticles and b) PbS powders after annealing at 600℃ for 3h with H2/Ar atmosphere. -- Figure S4. Histograms of the grain size distribution obtained from the cross section SEM image of the a) PbS pellet without reduction process, and b) PbS pellet with reduction process. SEM images are shown in Figure 3. -- Figure S5. XRD patterns of the Pb1-xCuxS a) nanoparticles and b) annealed powder. -- Figure S6. a) XRD patterns of the SPS sintered Pb1-xCuxS pellets; b) Expanded view of the regions corresponding to the PbS (200) diffraction peak. -- Figure S7. The function of the Cu concentration on the lattice parameters of the Pb1-xCuxS pellets: a) Lattice parameter a=b=c (Å); b) Volume of Cell (Å 3). -- Figure S8. Cross-section SEM image and EDX compositional maps of a Pb0.955Cu0.045S pellet. -- Figure S9. EELS chemical composition maps obtained from the red squared area of the STEM micrograph of the Pb0.955Cu0.045S pellet. -- Table S1. Pb1-xCuxS nanoparticle composition as measured by SEM-EDX and crystal domain size as obtained from XRD data using Scherrer equation. -- Table S2. Hall charge carrier concentration (n), mobility () and effective mass (m*) of Pb1- xCuxS pellets at room temperature., Peer reviewed

14 pages. -- PDF file includes: Details of Theoretical calculations. -- Figure S1. (a) SEM images of the Bi2Se3 nanosheets. (b) XRD patterns of Bi2Se3 nanosheets. (c) HRTEM images of the Bi2Se3 nanosheets and its corresponding power spectrum. (d) EELS chemical composition maps obtained from the red squared area of the STEM micrograph. -- Figure S2. Bi 4f and Se 3d high-resolution XPS spectra. -- Figure S3. XRD pattern of I-Bi2Se3/S. -- Figure S4. TGA curve of I-Bi2Se3/S composite measured in N2 with a sulfur loading ratio of 70.2 wt%. -- Figure S5. Nitrogen adsorption-desorption isotherms of as synthesized I-Bi2Se3 and IBi2Se3/S composites. -- Figure S6. DFT calculation results of optimized geometrical configurations of the surface (110) of Bi2Se3 with LiPS (Li2S, Li2S2, Li2S4, Li2S6, Li2S8 and S8). -- Figure S7. DFT calculation results of optimized geometrical configurations of the surface (110) of I-Bi2Se3 with LiPS (Li2S, Li2S2, Li2S4, Li2S6, Li2S8 and S8). -- Figure S8. Optimized adsorption configuration of Li2S decomposition on Bi2Se3. -- Figure S9. First five cycles of CV curves of (a) I-Bi2Se3/S, (b) Bi2Se3/S and (c) Super P/S performed at a scan rate of 0.1 mV s−1. -- Figure S10. Differential CV curves of (a) I-Bi2Se3/S, (c) Bi2Se3/S and (e) Super P/S. The baseline voltage and current density are defined as the value before the redox peak, where the variation on current density is the smallest, named as dI/dV=0. -- Figure S11. CV curves of (a) Bi2Se3/S, (b) Super P/S and (c) Plot of CV peak current for peaks C1, C2, and A versus the square root of the scan rates. -- Figure S12. The CV curve of I-Bi2Se3 as electrode measured in symmetric coin cell using an electrolyte without Li2S6. -- Figure S13. (a) Charge, and (b) discharge profiles of I-Bi2Se3/S, Bi2Se3/S, and Super P/S electrodes showing the overpotentials for conversion between soluble LiPS and insoluble Li2S2/Li2S. -- Figure S14. Galvanostatic charge−discharge profiles of (a) Bi2Se3/S and (b) Super P/S at different current densities range from 0.1C to 4C. -- Figure S15. (a,b) EIS spectra of (a) Bi2Se3/S and (b) Super P/S coin cells before and after cycling. The solid line corresponding to the fitting result from the equivalent circuit (c) and (d), and the Rs, Rin, Rct, and Zw stand for the resistance of the electrolyte, insoluble Li2S2/Li2S layer, interfacial charge-transportation, and semi-infinite Warburg diffusion, respectively; and CPE stands for the corresponding capacitance. (e) Different resistances of three coin cells were obtained from the equivalent circuit. -- Figure S16. XRD patterns of electrode materials after 100 cycles at 1C. -- Figure S17. Galvanostatic charge/discharge profiles of I-Bi2Se3/S at 0.5C under a lean electrolyte condition with a high sulfur loading of 5.2 mg cm-2. -- Figure S18. (a) SEM image of the Li-anode after cycling; (b) EDX mapping image of Lianode showing sulfur signal after cycling. -- Figure S19. SEM image of the cathode material after cycling, EDX spectra and EDX elemental maps for S, Se, Bi and I. -- Figure S20. I-Bi2Se3 optimized configuration as calculated by DFT. The distance between I and Bi is 3.15 Å, which is similar values than the bond lengths in bulk BiI3. -- Table S1 Summary of the comparison of I-Bi2Se3 electrochemical performance as host cathode for LSBs with state-of-the-art Bi-based or Se-based materials., Peer reviewed

30 pages. -- PDF includes: Characterization. -- Density functional theory (DFT) calculations. -- Computational property description. -- Fig. S1. EDS composition of the ternary alloys: FeCoNi, MnFeNi, MnCoNi, and MnFeCo. -- Fig. S2. XRD pattern of the ternary alloys: FeCoNi, MnFeNi, MnCoNi, and MnFeCo. -- Fig. S3. (a) ICP-OES composition, (b) XRD pattern, (c) TEM image, and (d) HRTEM images of a MnFeCoNi quaternary alloy. -- Fig. S4. (a) ICP-OES composition, (b) XRD pattern, (c) TEM image and EDS chemical composition maps, and (d) HRTEM images of a CuMnFeCoNi HEA. -- Fig. S5. Slices of electron density difference of CrMnFeCoNi in (a) side view, (b) front view, and (c) top view. The contour around the atoms represents electron accumulation (red) or electron depletion (blue). -- Fig. S6. Slices of electron density difference of CuMnFeCoNi in (a) side view, (b) front view, and (c) top view. The contour around the atoms represents electron accumulation (red) or electron depletion (blue). -- Fig. S7. OER performance of the ternary alloys. (a) LSV curves, (b) corresponding overpotential at 10 mA/cm2, (c) corresponding Tafel plots, and (d) EIS spectra. -- Fig. S8. (a-g) CV curves with different scan rates of different HEA, quaternary alloy, and ternary alloys in 1.0 M KOH showing the double layer capacitance without electrochemical reactions. (h) Current density at 0.961V vs. RHE plotted against the scan rate and fitted to a linear region to estimate the capacitance. -- Fig. S9. ICP-OES composition of a CrMnFeCoNi HEA after stability test. -- Fig. S10. XRD pattern of CrMnFeCoNi before and after OER stability measurements. -- Fig. S11. HRTEM image of CrMnFeCoNi after OER measurements. -- Fig. S12. In situ Raman spectra of CrMnFeCoNi during OER measurements. -- Fig. S13. High-resolution XPS spectra of CrMnFeCoNi HEA after OER stability measurements. -- Fig. S14. H2O2 yield vs. potential from MnFeCoNi, CrMnFeCoNi, CuMnFeCoNi, and Pt/C. -- Fig. S15. Relaxed atomic configuration of the four fundamental steps of OER/ORR for the MnFeCoNi structure. -- Fig. S16. Relaxed atomic configuration of the four fundamental steps of OER/ORR for the CuMnFeCoNi structure. -- Fig. S17. Galvanostatic discharge-charge curves with 10 min discharge and 10 min charge cycles at a current density of 5 mA/cm2. -- Fig. S18. Galvanostatic discharge-charge curves with 10 min discharge and 10 min charge cycles at a current density of 12 mA/cm2. -- Table S1. Atomic radius and electronegativity of different elements. -- Table S2. Mn 2p, Fe 2p, Co 2p and Ni 2p XPS binding energies of MnFeCoNi, CrMnFeCoNi, and CuMnFeCoNi. -- Table S3. Comparison of the OER performance of the CrMnFeCoNi HEA with recently reported high entropy alloy catalysts. -- Table S4. ICP-OES results of the amount of metallic elements in the electrolyte after long-term tests. -- Table S5. Comparison of the bifunctional activities of various state-of-the-art electrocatalysts for OER and ORR. -- Table S6. Comparison of the ZAB performances obtained using state-of-the-art air cathodes, Peer reviewed

34 pages. -- PDF includes supplementary figures: Figure S1. Rp of PCO infiltrated PBC oxygen electrode symmetrical cells with different mass per unit area infiltration and firing temperature, tested at a temperature of 700 to 500 oC. -- Figure S2. Short stability of Rp of BZCYYb symmetrical cells with bare PBC and PCO infiltrated PBC oxygen electrode with different infiltration mass per unit area and firing temperature, tested at 650 oC under flowing air with 3 vol.% H2O. -- Figure S3. the detailed SEM image of PCO catalyst on PBC oxygen electrode bone fired at (a) 800 °C (b) 900 °C and (c) 1000 °C for 2h. -- Figure S4. Short stability of Rp of BZCYYb symmetrical cells with (a) pure CeO2-δ, (b) Pr0.2Ce0.8O2-δ, and (c) Pr0.1Ce0.9O2-δ infiltrated PBC oxygen electrode with 15mg/cm2 and 900oC firing temperature, tested at 650 oC under flowing air with 3 vol.% H2O; (d) Comparison of Rp changes with time after infiltration of three catalysts. -- Figure S5. XRD patterns of BZCYYb electrolyte, PBC oxygen electrode, and chemical compatibility results of PBC-BZCYYb powder. -- Figure S6. In situ XRD patterns of PBC (a) and PCO-PBC (b) powders in wet air (3% H2O) at 650 oC for 6 h. -- Figure S7. EIS of symmetrical cells with oxygen electrode of bare PBC (a) and PCO-PBC (b) at different oxygen partial pressure of 0.1-1.0 at 650 oC under open-circuit voltage condition. -- Figure S8. Effects of water partial pressure (pH2O) on the DRT functions of Bare PBC. -- Figure S9. Electrochemical behaviors evolution of single cells under a different partial pressure of water. -- Figure S10. EIS curves (a) and (b) Typical IVP curves of BZCYYb single cell with a bare PBC oxygen electrode measured from 700 to 600 oC, using 3 vol.% humidified H2 as fuel, and ambient air as oxidant. -- Figure S11. Performance evaluation of single cells under ambient air. -- Figure S12. Thermalgravimetric analyses of PBC and PCO-PBC in the air from RT to 900 oC. -- Figure S13. Detailed SEM image of bare PBC oxygen electrode. -- Figure S14. TEM micrograph (a) and EDX element mapping (b) of PBC grains treated under 3 vol.% H2O at 650 oC after 100 h. -- Figure S15. EDX element mapping and HAADF of initial PBC and initial PCO-PBC. -- Figure S16. XPS profiles of Co 2p and Ba 3d in the initial PBC (a), PCO-PBC (c), and the ones after being treated with H2O for 100 h (b) and (d), respectively. -- Figure S17. Typical I-V curves of the R-PCECs were measured before and after the test (~100 hours) at 650 oC in the humid air. -- Figure S18. Stability of the single cell with a PCO-PBC air electrode, tested in EL mode under different current densities of 0.50, 0.75, and 1.00 A cm-2 at 650 oC for 20 h. -- Table S1. The activation energy of PCO infiltrated PBC oxygen electrode symmetrical cells with different mass per unit area infiltration and firing temperature. -- Table S2. Comparison between the experimental and the theoretical bulk plane spacing distances and angles between planes. -- Table S3. Comparison between the experimental and the theoretical bulk plane spacing distances and angles between planes. -- Table S4. Comparison between the experimental and the theoretical bulk plane spacing distances and angles between planes. -- Table S5. Comparison between the experimental and the theoretical bulk plane spacing distances and angles between planes. -- Table S6. The relationship between elementary reaction and n. -- Table S7. The rate-determining steps for both PBC and PCO-PBC oxygen electrodes. -- Table S8. Performance comparison of our cells and other high-performance cells reported recently. -- Table S9. Performance comparison of our cell and other cells reported by others, Peer reviewed

9 pages. -- Contents: Supplementary Note 1: Two-dimensional hole gas properties. -- Supplementary Note 2: PtSiGe properties. -- Supplementary Note 3: SNS-QPC measurements. -- Supplementary Note 4: NS-QPC measurements. -- Supplementary Note 5: SQUID measurements. -- Supplementary Note 6: 1D array. -- Supplementary Note 7: Key metrics, Peer reviewed

The raw data are organized in folders based on the kind of device presented in the paper. The Juppyter notebooks contain the code for analyzing and plotting the data, there is one notebook for each figure of the papaer and supplementary. The scripts used to import the datasets of different kinds are contained in util_scripts, along with some other useful functions for plotting and formatting., Fig2 - SNS.ipynb, Peer reviewed