The formation of ammonia (NH 3 ) as a byproduct during the operation of a three-way catalyst (TWC) in a simulated exhaust stream was investigated using a commercially available Pd/Rh TWC under steady-state and lean/rich cycling conditions. Ion molecular reaction-mass spectrometry was applied to determine NO, NO 2 , and NH 3 concentrations at a time resolution of 0.6 s. Catalyst aging was shown to result in a significant increase in the amount of NH 3 formed, which has received limited attention in the literature to date. The selectivity toward NH 3 formation has been shown to increase with the decrease in the oxygen storage capacity (OSC) of a TWC induced by thermal aging. NH 3 has been shown to mainly form within the exhaust temperature range of 250−550 °C. Typical lambda and rich operational condition duration periods found in vehicle test procedures were also employed to investigate their effects on NH 3 formation. The results suggest that a decrease in the lambda and/or an increase in the duration of rich operating conditions will lead to an increase in the selectivity toward NH 3 formation. Improving the OSC of TWCs and effectively controlling the lambda near to 1.0 with limited duration in rich operating conditions are therefore significant factors in the reduction of NH 3 emissions.

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High performance solar cells fabricated from an easily synthesized donor‐acceptor polymer show maximum power point up to 6.0 mW cm−2, with an open‐circuit voltage of 0.89 V, short‐circuit current density of 10.5 mA cm−2 and fill factor of 0.64, making this polymer a particularly promising candidate for high‐efficiency low‐cost polymer solar cells.

Controlled reductive assembly of capped Keggin anions [PMo(12)O(40)(ML(m))(n)](3-) has been achieved by reduction of [PMo(12)O(40)](3-) with sodium-mercury amalgam in the presence of metal halides, as exemplified by the rational syntheses of mono-capped [PMo(12)O(40){Co(MeCN)(2)}](3-) and bi-capped [PMo(12)O(40)(VO)(2)](3-) and [PMo(12)O(40)Sb(2)](3-).