This study demonstrates an electron beam physical vapour deposition approach as an alternative stainless steel thin films fabrication method with controlled layer thickness and uniform particles distribution capability. The films were fabricated at a range of starting electron beam power percentages of 3–10%, and thickness of 50–150 nm. Surface topography and wettability analysis of the samples were investigated to observe the changes in surface microstructure and the contact angle behaviour of 20 °C to 60 °C deionised waters, of pH 4, pH 7, and pH 9, with the as-prepared surfaces. The results indicated that films fabricated at low controlled deposition rates provided uniform particles distribution and had the closest elemental percentages to stainless steel 316L and that increasing the deposition thickness caused the surface roughness to reduce by 38%. Surface wettability behaviour, in general, showed that the surface hydrophobic nature tends to weaken with the increase in temperature of the three examined fluids.

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In this work, a novel hydrogen production process (Integrated Chemical Looping Water Splitting "ICLWS") has been developed. The modelled process has been optimized via heat integration between the main process units. The effects of the key process variables (i.e. the oxygen carrier-to-fuel ratio, steam flow rate and discharged gas temperature) on the behaviour of the reducer and oxidiser reactors were investigated. The thermal and exergy efficiencies of the process were studied and compared against a conventional steammethane reforming (SMR) process. The process economic feasibility was finally evaluated by evaluating the corresponding CAPEX, OPEX and the first-year plant cost per kg of the hydrogen produced. The results show that the thermal efficiency of the ICLWS process is improved by 31.1% compared to the baseline (Chemical Looping Water Splitting without heat integration) process. Also, the hydrogen efficiency and the effective efficiencies were higher by 11.7% and 11.9%, respectively compared to the SMR process. The sensitivity analysis showed that the oxygen carrier-to-methane and -steam ratio can impact the discharged gas and solid conversions from both the reducer and oxidiser. Also, unlike for the oxidiser, the temperature of the discharged gas and solids from the reducer had an impact on the gas and solid conversion. The economic evaluation of the process showed hydrogen production costs of $1.41 and $1.62 per kilogram of hydrogen produced for ZrO2 and MgAl2O4 as support materials, respectively. This value was 14% and 1.2% lower for the SMR process with MgAl2O4 and ZrO2 as support material, respectively.