Judicious Ligand Design in Ruthenium Polypyridyl CO2 Reduction Catalysts to Enhance Reactivity by Steric and Electronic Effects

A series of RuII polypyridyl complexes of the structural design [RuII(R−tpy)(NN)(CH3CN)]2+ (R−tpy=2,2′:6′,2′′-terpyridine (R=H) or 4,4′,4′′-tri-tert-butyl-2,2′:6′,2′′-terpyridine (R=tBu); NN=2,2′-bipyridine with methyl substituents in various positions) have been synthesized and analyzed for their ability to function as electrocatalysts for the reduction of CO2 to CO. Detailed electrochemical analyses establish how substitutions at different ring positions of the bipyridine and terpyridine ligands can have profound electronic and, even more importantly, steric effects that determine the complexes’ reactivities. Whereas electron-donating groups para to the heteroatoms exhibit the expected electronic effect, with an increase in turnover frequencies at increased overpotential, the introduction of a methyl group at the ortho position of NN imposes drastic steric effects. Two complexes, [RuII(tpy)(6-mbpy)(CH3CN)]2+ (trans-[3]2+; 6-mbpy=6-methyl-2,2′-bipyridine) and [RuII(tBu−tpy)(6-mbpy)(CH3CN)]2+ (trans-[4]2+), in which the methyl group of the 6-mbpy ligand is trans to the CH3CN ligand, show electrocatalytic CO2 reduction at a previously unreactive oxidation state of the complex. This low overpotential pathway follows an ECE mechanism (electron transfer–chemical reaction–electron transfer), and is a direct result of steric interactions that facilitate CH3CN ligand dissociation, CO2 coordination, and ultimately catalytic turnover at the first reduction potential of the complexes. All experimental observations are rigorously corroborated by DFT calculations

Intercultural parenting in Australia: managing cultural differences

This study employed a qualitative and social constructionist approach to examine cultural differences in intercultural parenting and how parents negotiated cultural differences. Semistructured, in-depth interviews were conducted with 14 intercultural couples/parents. Thematic analysis was used to analyze data and understand the meanings of participants’ experiences. The findings revealed that while intercultural couples experienced several similar aspects of parenting experienced by monocultural couples, their experiences were exacerbated because of the cultural differences. The most common descriptions of differences and uniqueness in parenting were identified as (a) discipline, (b) sleep patterns, (c) cultural taboos refood and traditional medical practices, (d) children’s socialization process, (e) education, (f) language and communication, (g) role of children, and (h) the role of extended families. Five major conflict resolution strategies were identified: (a) communication, (b) compromise, (c) sphere of rule, (d) asymmetrical decision-making, and (e) individual traits. Practical implications for therapists and counsellors working with intercultural parents/couples are discussed

The experience of intercultural parenting in Australia

The growth of immigration, globalisation, social diversity, and advances in global technology have contributed to an increase in intercultural relationships and parenting in Australia. Much of the Australian research has focussed on parenting styles among different cultural groups and the impact on children, rather than the experiences of the parents. This research sought to address this gap. This study aimed to explore the experiences of intercultural parents raising their children together. It sought to explore the challenges and strategies parents applied in negotiating cultural differences in their parenting approaches, as well as the strengths and opportunities of intercultural parenting. The study aimed to focus on the experiences of intercultural parents who do not seek professional help. This study used a qualitative research method and social constructionist paradigm to delineate the experiences of intercultural parents. Semi-structured conjoint interviews were used to collect data from 14 couples living in the State of Queensland. Thematic analysis was used to code and analyse data. The analysis revealed four major themes of the couples’ experiences: (1) cultures coming together; (2) power relations; (3) reverse acculturation/enculturation; and (4) making intercultural parenting work. A number of organisational policy, clinical implications for therapists and recommendations for future research are suggested

Enhancement of the Catalytic Activity of a Macrocyclic Cobalt(II) Complex for the Electroreduction of O_2 by Adsorption on Graphite

In solution, the [(tim)Co]^(2+) complex (tim = 2,3,9,10-tetramethyl-1,4,8,11-tetraazacyclotetradeca-1,3,8,10-tetraene) reacts only slowly with O_2, but upon adsorption on graphite electrodes it becomes an active catalyst for the reduction of O_2 to H_2O_2. The remarkable enhancement in catalytic activity is attributed to a higher affinity for O_2 of the adsorbed complex as a result of its interaction with functional groups on the surface of roughened or oxidized graphite. A possible catalytic mechanism is proposed