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Improving the water oxidation performance of abundantly available materials, such as stainless steel (SS), with notable intrinsic electrocatalytic oxygen evolution reaction (OER) activity due to the presence of Ni and Fe is highly anticipated in water splitting. A new method for promoting the corrosion of stainless steel (304) was found which assisted the uniform formation of oxygen evolution reaction (OER) enhancing NiO incorporated Fe2O3 nanocrystals with the simultaneous reduction in the surface distribution of OER inactive Cr. An equimolar combination of KOH and hypochlorite was used as the corroding agent at 180 °C. The effect of corrosion time on the OER activity was studied and found that better water oxidation performance was observed when the corrosion time was 12 h (SS-12). The SS-12 showed an abnormal enhancement in OER activity compared to the untreated SS and other optimized versions of the same by requiring very low overpotentials of 260, 302, and 340 mV at the current densities of 10, 100, and 500 mA cm–2 along with a very low Tafel slope in the range of 35.6 to 43.5 mV dec–1. These numbers have certainly shown the high-performance electrocatalytic water oxidizing ability of SS-12. The comparative study revealed that the state-of-the-art IrO2 had failed to compete with our performance improved catalytic water oxidation anode “the SS-12”. This fruitful finding indicates that the SS-12 has the potential to be an alternate anode material to precious IrO2/RuO2 for alkaline water electrolyzers in future.

Highly conducting freestanding graphene (FSG) was synthesized by the simple vacuum filtration method and utilized as a cathode current collector for (fluorine doped tin oxide) FTO free quasi‐dye sensitized solar cell (q‐DSSC). Subsequently,conducting polymers (CPs) viz., polyaniline (PANI) and poly(3,4‐ethylene‐di‐oxythiophene) (PEDOT) was decorated on FSG surface by electrochemical polymerization which acts as a electrocatalytst for Pt free q‐DSSC. Entirely, the FSG/CPs affords as a novel cathode architecture for FTO/Pt free electrode for q‐DSSCs. Remarkably, the FSG paper electrode exhibits lower sheet resistance (9‐11 Ω sq‐1) than the FTO which was directly utilized as current collector. Interestingly, the FSG/CPs based cathode shows an improved electro‐catalytic behaviour towards tri‐iodide reduction and in particularly, the photovoltaic performance of FSG/PEDOT shows power conversion efficiency (PCE) of 5.4 % compared with Pt/FTO of 5.1 %. It can be stated that synergetic effect of FSG/PEDOT proves to be a cost effective and efficientsubstitute for cathodes in q‐DSSC.

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Copper has rapidly replaced gold as the preferred wire bonding material in microelectronic packaging due to its lower cost and many performance advantages. However, halides induced corrosion-related failures need to be carefully controlled to ensure maximum bonding reliability. Literature reported corrosion studies mostly focus on intermetallic compounds as the corrosion vulnerability. Utilizing a novel corrosion screening approach, we established that the bimetallic contact between Cu balls and Al bond pad is the real driver for the observed heavy Al pad corrosion induced by chloride ions [1]. We identified, for the first time, H2 evolution was the coupling cathodic half reaction to the Al bond pad corrosion. With these improved mechanistic insights, we developed an effective corrosion inhibition strategy that utilizes chemical vapor deposition to selectively bond corrosion inhibitors to these critical Cu ball/Al pad interfaces. A new corrosion-screening platform was developed to evaluate the effectiveness of this inhibitor protection treatment. After intentionally loaded chloride contaminants on the die surface, the molded Cu wire bonded devices with selected inhibitor treatment were subjected to PCT stress tests. The subsequent failure analyses, showed selected inhibitor treatment is highly effective of preventing Al bond pad corrosion even under the massive attack of heavy Cl− ion contamination and extensive delamination.