<?php
use Microsoft\Graph\GraphServiceClient;
use Microsoft\Graph\Generated\Models\Channel;
use Microsoft\Graph\Generated\Models\ChannelMembershipType;
$graphServiceClient = new GraphServiceClient($tokenRequestContext, $scopes);
$requestBody = new Channel();
$requestBody->setDisplayName('Architecture Discussion');
$requestBody->setDescription('This channel is where we debate all future architecture plans');
$requestBody->setMembershipType(new ChannelMembershipType('standard'));
$result = $graphServiceClient->teams()->byTeamId('team-id')->channels()->post($requestBody)->wait();