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Electrocatalytic nitrogen reduction (eNRR) offers a green pathway for NH3 production from N2 and H2O under ambient conditions. Transition metal oxynitrides (TMOxNy) are among the most promising catalysts but face challenges in achieving high yield and faradaic efficiency (FE). This work develops a hybrid WOxNy/WO3 catalyst with a unique heterogeneous interfacial complexion (HIC) structure. This design enables in situ generation and delivery of highly active hydrogen atoms (H*) in acidic electrolytes, promoting nitrogen hydrogenation and formation of nitrogen vacancies (Nv) on the WOxNy surface. This significantly enhances the selectivity of eNRR for NH3 synthesis while suppressing hydrogen evolution reaction (HER). A simple two-step fabrication process—microwave hydrothermal growth followed by plasma-assisted surface nitridation—was developed to fabricate the designed catalyst electrode, achieving an NH3 yield of 3.2 × 10-10 mol·cm-2·s-1 with 40.1% FE, outperforming most TMN/TMOxNy electrocatalysts. Multiple control experiments confirm that the eNRR follows a HIC-enhanced Mars-van Krevelen (MvK) mechanism. 

In this paper, we present a novel Model Predictive Control method for autonomous robot planning and control subject to arbitrary forms of uncertainty. The proposed Risk- Aware Model Predictive Path Integral (RA-MPPI) control utilizes the Conditional Value-at-Risk (CVaR) measure to generate optimal control actions for safety-critical robotic applications. Different from most existing Stochastic MPCs and CVaR optimization methods that linearize the original dynamics and formulate control tasks as convex programs, the proposed method directly uses the original dynamics without restricting the form of the cost functions or the noise. We apply the novel RA-MPPI controller to an autonomous vehicle to perform aggressive driving maneuvers in cluttered environments. Our simulations and experiments show that the proposed RA-MPPI controller can achieve similar lap times with the baseline MPPI controller while encountering significantly fewer collisions. The proposed controller performs online computation at an update frequency of up to 80 Hz, utilizing modern Graphics Processing Units (GPUs) to multi-thread the generation of trajectories as well as the CVaR values. 

The nitrogen cycle needed for scaled agriculture relies on energy- and carbon-intensive processes and generates nitrate-containing wastewater. Here we focus on an alternative approach—the electrified co-electrolysis of nitrate and CO2 to synthesize urea. When this is applied to industrial wastewater or agricultural runoff, the approach has the potential to enable low-carbon-intensity urea production while simultaneously providing wastewater denitrification. We report a strategy that increases selectivity to urea using a hybrid catalyst: two classes of site independently stabilize the key intermediates needed in urea formation, *CO2NO2 and *COOHNH2, via a relay catalysis mechanism. A Faradaic efficiency of 75% at wastewater-level nitrate concentrations (1,000 ppm NO3− [N]) is achieved on Zn/Cu catalysts. The resultant catalysts show a urea production rate of 16 µmol h−1 cm−2. Life-cycle assessment indicates greenhouse gas emissions of 0.28 kg CO2e per kg urea for the electrochemical route, compared to 1.8 kg CO2e kg−1 for the present-day route. 

In this paper we study Zimmer's conjecture for $$C^{1}$$ actions of lattice subgroup of a higher-rank simple Lie group with finite center on compact manifolds. We show that when the rank of an uniform lattice is larger than the dimension of the manifold, then the action factors through a finite group. For lattices in $${\rm SL}(n, {{\mathbb {R}}})$$ , the dimensional bound is sharp.