The present work demonstrates an electroless (e-less) deposition of Pb monolayer on Au and Cu surface whose morphology and properties resemble its underpotentially deposited counterpart. Our results and analysis show that the e-less Pb monolayer deposition is a surface selective, surface controlled, self-terminating process. Results also show that the electroless Pb monolayer deposition is enabling a phenomenon for new deposition method called "electroless atomic layer deposition" (e-less ALD). Here, the e-less Pb monolayer serves as reducing agent and sacrificial material in surface limited redox replacement reaction with noble metal ions such as Pt , i.e., Pt deposition. The e-less ALD is highly selective to the metal substrates at which Pb forms the e-less monolayer. The full e-less ALD cycle leads to an overall deposition of a controlled amount of the noble metal. Repetition of the two-step e-less ALD cycle an arbitrary number of times leads to formation of a highly compact, smooth, and conformal noble metal thin film with applications spanning from catalyst synthesis to semiconductor technology. The process is designed for (but not limited to) aqueous solutions that can be easily scaled up to any size and shape of the substrate, deeming its wide applications.

We present results exploring different concepts for Pb monolayer mediated thin film growth of Cu on Ru(0001) and Co on polycrystalline Cu substrates. Both systems are of considerable importance in microchip fabrication technology and they exhibit a three dimensional growth at room temperature which somewhat limits their application. The Pb monolayer mediation of the growth process is explored by having its role as a surfactant, flux mediator or as a sacrificial layer in deposition via surface limited redox replacement protocol. Electrochemical and STM results suggest that Pb monolayer induces 2D Cu growth on Ru(0001) and the growth mechanism is very dependent on the Pb mediation role. The surfactant properties of electrolessly deposited Pb monolayer are also studied during electroless deposition of Co on polycrystalline Cu. The benefit of Pb monolayer mediation of the Co growth process was manifested by 2D Co thin film morphology, high quality of the grain boundaries, and improved magnetic properties.

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In this work, we report a facile preparation of biocomposites using a chitosan matrix that is reinforced with morphed graphene in amounts from 1 to 5 wt % C. The composites are processed by milling and conventional sintering. The morphed graphene additions show clear improvements in mechanical properties, having a direct correlation with temperature in particular for 180 °C. Higher temperatures are detrimental to chitosan and the properties drop because chitosan degrades. Mechanical properties in the composite such as yield strength and compressive strength increase between 40 and 50% with respect to the pure chitosan samples. The Young's modulus presents a drop of approximately 10%, but the fracture toughness increases up to 3.5 fold. The properties of our sustainable composites are comparable to those seen in polymers such as polyethylene, polypropylene, nylon, and poly(methyl methacrylate), among other commodity or single use plastics. The enhancement in the mechanical properties is attributed to the morphed graphene embedded chitosan matrix that generates a network of intergranular "anchors" that hold the chitosan crystals in place, preventing failure. The composites can be molded into near-net-shape products, machined, or shaped using various methods including laser lithography. These studies demonstrate the feasibility of fabricating biocomposites with different architectures and sizes for disposable structural components. Both chitosan and the composites are compostable and biodegradable with the potential to sustain plant growth when discarded. In addition, morphed graphene and chitosan are produced from byproducts or waste, which may result in a negative carbon footprint on the environment.

Electromagnetic induction is essential for functioning of the analog circuits used in cell phones, MEMS devices and other power related electronics. In order to meet the demand of higher efficiency and minimum magnetic losses in packaging industry, we have developed solution chemistry1 , 2 for electrodeposition of CoNiFeX (X=S,O,P,B,V) thin films (thickness=500 nm) with high magnetic moment (HMM) and >500 permeability at >500 MHz frequency; >100μΩ-cm resistivity; >1.5 T magnetic moment. The CoNiFeX alloys are fully compatible with existing manufacturing concepts in semiconductor industry. Direct current (DC) and pulse current3 (PC) deposition methods for CoNiFeX alloys is employed to demonstrate control over BCC/FCC crystal structure by tuning transport conditions during electrodeposition. The structure of CoNiFeX alloys is characterized with average grain size of 15-20 nm which consequently yields coercivity values of CoNiFeX alloy films between 8-15 Oe at 500 nm thickness. CoNiFe alloys produced by DC and PC deposition have magnetic moment of 1.8 T, which is optimized to 2.2 T with addition of X (X=S,O,P,B,V) as additives4. More than 100% increase in the resistivity of deposited CoNiFe alloys is demonstrated with controlled concentration of additives and Fe3+ ions as oxide precipitating agent5 without reduction in magnetic properties. All samples exhibit shiny surface finish and low stress. Thin film inductor devices are fabricated with CoNiFeX alloys to test magnetic properties at >500 MHz frequency, which would be discussed with testing data. Brankovic, S. R., Vasiljevic, N., Klemmer, T. J. & Johns, E. C. Influence of additive adsorption on properties of pulse deposited CoFeNi alloys. Journal of the Electrochemical Society 152, C196 (2005). Brankovic, S. R., Sendur, K. & Klemmer, T. J. Magnetic Materials, Processes, and Devices VII and Electrodeposition of Alloys. in Proceedings of the International Symposia 2002, 269 (Electrochemical Society, 2003). Puippe, J.-C. & Leaman, F. Theory and practice of pulse plating. (Amer Electroplaters Soc, 1986). Djokić, S. S. Electrodeposition of amorphous alloys based on the iron group of metals. Journal of the Electrochemical Society 146, 1824 (1999). George, J. et al. Oxide/hydroxide incorporation into electrodeposited CoFe alloys—Consequences for magnetic softness. Electrochimica Acta 110, 411–417 (2013).