Emerging co-synthesis of dimethyl oxalate and dimethyl carbonate using Pd/silicalite-1 catalyst with synergistic interactions of Pd and silanols

•An emerging route for co-synthesis of dimethyl oxalate and dimethyl carbonate.•Highly active, stable Pd/S-1 catalyst with TOF of 0.18 s−1 and stability of 200 h.•The catalytic performance strongly depended on the catalyst activation.•Heat treatment tuned the silanol defects around Pd species on the Pd/S-1 catalyst.•Synergistic interactions between zeolite silanols and Pd species were confirmed.