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In most electrochemical syntheses, reactions are happening at or near the electrode surface. For catalyzed reactions, ideally, the electrode surface would solely contain the catalyst, which then simplifies purification and lowers the amount of catalyst needed. Here, a new strategy involving phthalocyanines (Pc) to immobilize catalysts onto carbon electrode surfaces is presented. The large π structure of the Pc enables adsorption to the sp2-structure of graphitic carbon. TEMPO-modified Pc were chosen as a proof of concept to test the new immobilization strategy. It was found that the TEMPO-Pc derivatives functioned similarly or better than the widely used pyrene adsorption method. Interestingly, the new TEMPO-Pc catalyst appears to facilitate a cascade reaction involving both the anode and the cathode. The first step is the generation of an aryl aldehyde (anode) followed by the reduction of the aryl aldehyde in a pinacol-type coupling reaction at the cathode. The last step is the oxidation of a hydrobenzoin to create benzil. This work demonstrates the unique ability of electrochemistry and bifunctional catalysts to enable multistep chemical transformations, performing both reductive and oxidative transformations in one pot. 

Combining electrochemistry with microfluidics is attractive for a wide array of applications including multiplexing, automation, and high-throughput screening. Electrochemical instrumentation also has the advantage of being low-cost and can enable high analyte sensitivity. For many electrochemical microfluidic applications, carbon electrodes are more desirable than noble metals because they are resistant to fouling, have high activity, and large electrochemical solvent windows. At present, fabrication of electrochemical microfluidic devices bearing integrated carbon electrodes remains a challenge. Here, a new system for integrating polycaprolactone (PCL) and carbon composite electrodes into microfluidics is presented. The PCL : carbon composites have excellent electrochemical activity towards a wide range of analytes as well as high electrical conductivity (∼1000 S m −1 ). The new system utilizes a laser cutter for fast, simple fabrication of microfluidics using PCL as a bonding layer. As a proof-of-concept application, oil-in-water and water-in-oil droplets are electrochemically analysed. Small-scale electrochemical organic synthesis for TEMPO mediated alcohol oxidation is also demonstrated. 

An inexpensive, transparent, catalytic, and highly stable material is the holy grail for a dye sensitized solar cell (DSSC) cathode. Despite a near exponential increase in research effort on DSSC cathodes, materials approaching this ideal have yet to be found. Transparent cathodes allow for front and back illumination of the solar cell, enable alternative anode materials and cell designs, and are important both for fundamental research and commercialization of DSSCs. In this work, thin polymeric films of nickel tetraminophthalocyanine (NiTAPc) were tested as a catalytic cathode material in Co(Bipy)-mediated DSSCs. The thin films are highly transparent with a transmittance at 550 nm (T550) of over 95% while maintaining an R ct value below 1.3 Ω cm 2 . The NiTAPc films are inexpensive, fast and easy to generate, and stable to 2000 cyclic voltammetry cycles. Long-term film stability was not realized, and a rise in the R ct over time (days) occurred. However, poly-NiTAPc still represents one of the most transparent and catalytic materials reported to date. While historically phthalocyanines (Pc) have been studied as a dye/sensitizer, this first report of phthalocyanine use as a cathode material demonstrates they have utility on both sides of the DSSC. 

Monitoring reactive intermediates can provide vital information in the study of synthetic reaction mechanisms, enabling the design of new catalysts and methods. Many synthetic transformations are centred on the alteration of oxidation states, but these redox processes frequently pass through intermediates with short life-times, making their study challenging. A variety of electroanalytical tools can be utilised to investigate these redox-active intermediates: from voltammetry to in situ spectroelectrochemistry and scanning electrochemical microscopy. This perspective provides an overview of these tools, with examples of both electrochemically-initiated processes and monitoring redox-active intermediates formed chemically in solution. The article is designed to introduce synthetic organic and organometallic chemists to electroanalytical techniques and their use in probing key mechanistic questions.