We　report　a　simple　strategy　for　realizing　the　tunable　structure　distortion　of　graphitic　carbon　nitride　(g-C3N4)　layers　by　H2　post　calcination　to　improve　the　intrinsic　electronic　structure　and　the　photocatalytic　performances　of　g-C3N4　samples.　In　comparison　with　the　O2　or　N2　post　treatment,　the　H2-modified　g-C3N4　develops　new　optical　absorption　above　460nm　and　enhances　photocatalytic　activity　for　NO　removal.　The　combined　characterization　results　reveal　that　H2　heating　induced　the　structure　distortion　of　g-C3N4　layers　is　originated　from　the　creation　of　amino　groups　within　the　structure　and　generation　of　the　strong　hydrogen　bonding　interactions　between　layers.　The　distorted　structure　allows　n-π*　electron　transitions　in　g-C3N4　to　increase　visible-light　absorption.　The　structure　distortion　also　enables　more　electrons　to　be　available　for　initiating　the　photocatalytic　reaction　and　the　separation　of　photogenerated　charge　carriers　in　g-C3N4.　This　work　provides　a　simple　strategy　for　realizing　the　tunable　structure　distortion　of　g-C3N4　layers　to　adjust　its　electronic　structure　and　photocatalysis.　©　2015　Elsevier　B.V.