In this study, we utilize scalable, flame spray synthesis to develop defective ZnO nanomaterials for the concurrent generation of H 2 and CO during electrochemical CO 2 reduction reactions (CO 2 RR). The designed ZnO achieved a H 2 /CO ratio of ~1 with a large current density (j) of 40 mA cm -2 during longterm continuous reaction at a cell voltage of 2.6 V. Through in-situ atomic pair distribution function analysis, we explored the remarkable stability of our ZnO structures, addressing the knowledge gap in understanding the dynamics of oxide catalysts during CO 2 RR. Through optimization of synthesis conditions, ZnO facets were modulated which were shown to affect reaction selectivity, in agreement with theoretical calculations. These findings and insights on synthetic manipulation of active sites in defective metal-oxides can be used as guidelines to develop active catalysts for syngas production for renewable power-to-X to generate a range of fuels and chemicals.

No abstract

Future energy security and environmental issues are major driving forces for increased biomass utilization globally and especially in developing countries like Pakistan. For efficient utilization of indigenous biomass resources in the future energy mix, it is important to gain knowledge of current energy system in various sectors. Some of the technologies and initiatives are under development to achieve transition from non-renewable resources to renewable resources, and reducing fossil fuel dependency and greenhouse gas emissions. Recently, number of proposals has been presented for the development of sustainable biofuels production methods for promise for accelerating a shift away from an unsustainable approach to possible sustainable production practices or a sustainable social, economic and environment. This article presents an extensive literature review of the biomass-based renewable energy potential in Pakistan based on current energy scenario and future perspectives. It also highlights the availability of the indigenous and local biomass resources and potential biomass conversion technologies to convert such resources to bioenergy. The drivers for utilization of indigenous biomass resources in future energy mix and challenges regarding awareness among stakeholders and R&D to fill knowledge gaps are economically restraints. The article concludes with suggestions on future directions and policies for effective implementation of biomass based renewable energy production.

Coupled metal-nitrogen-carbon (M-Nx-C) materials show great promise as platinum-group-metal (PGM) free catalysts for oxygen reduction reaction (ORR). Herein, we report a facile strategy to construct atomically dispersed Co, Fe dual...

Ammonia is an industrially relevant chemical that can be directly synthesized from water and air using renewable energy through the electrochemical nitrogen reduction reaction (NRR). However, because of the inert nature of nitrogen, current attempts at synthesizing ammonia under aqueous conditions result in low selectivity and yield rates. The poor electrocatalytic performance is mainly attributed to competing hydrogen evolution, underexposed active sites, inadequate electrode contact, and poor stabilization/ destabilization of key reaction intermediates. Herein, we present a catalyst composed of MoO 2 with surface vacancies dispersed over conductive carbon nanowires that mitigates these obstacles for NRR by providing a high surface area with stable catalytic sites and an underlying conductive support, where a variety of X-ray spectroscopy techniques are used to characterize the MoO 2 catalyst. This uniquely engineered catalyst exhibits exceptional Faradaic efficiencies of over 30% and yields of 21.2 μg h −1 mg −1 at a low potential of −0.1 V vs RHE under ambient aqueous conditions.